Congenital Heart Surgery

Midterm Outcomes of the Supported Ross Procedure in Children, Teenagers and Young Adults

Midterm Outcomes of the Supported Ross Procedure in Children, Teenagers and Young Adults. Riggs KW, Colohan DB, Beacher DR, Alsaied T, Powell S, Moore RA, Ginde S, Tweddell JS. Semin Thorac Cardiovasc Surg. 2019 Dec 18. pii: S1043-0679(19)30391-0. doi: 10.1053/j.semtcvs.2019.10.020. [Epub ahead of print] PMID: 31863831 Similar Articles Select Item 31845632   Take Home Points: The Ross procedure is an excellent option for aortic valve replacement in children and young adults, but dilation of the pulmonary autograft can lead to the need for further surgery. The supported Ross procedure has been designed to minimize the risk of pulmonary autograft dilation and this single-center review supports this decreased risk with mid-term data on 40 patients.   Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch: The Ross procedure involves replacing the aortic valve with a pulmonary autograft and then using a pulmonary homograft for replacement of the pulmonary valve and main pulmonary artery. This procedure has proven very effective for younger patients and avoids the need for anticoagulation. However, the pulmonary autograft can dilate over time creating neoaortic root dilation and aortic regurgitation, necessitating further surgery. In 2005, a modified version of the Ross procedure was described by Ungerleider et al. The modification involved the use of a slightly oversized Dacron tube graft to surround and support the pulmonary autograft to minimize the ability of the autograft to dilate with time. The mid-term results of the supported Ross procedure from two centers are presented here.   The authors used retrospective data from Cincinnati Children’s and Children’s Hospital of Wisconsin to evaluate 40 patients’ outcomes from 2005-2018. The study does not explicitly mention the detail that the senior author worked at both institutions during this time period and it does not specify how many surgeons performed the surgeries during this time period. The outcomes examined included survival, cardiac reintervention and aortic dimensions from serial echocardiograms. The patients ranged in ages from 10-35 years old (median age of 16 years) and median length of follow-up was 3.5 years (1.4-5.6 years) with only 3 patients followed for >10 years.   The graph depicting root dilation in this cohort is shown in graph 1 below. A z-score >2.5 was used as the cut off to define > mild dilation of the neoaortic root. Figure 1 gives a schematic drawing of the supported Ross procedure. The key component to the surgery is that the graft was sized ~ 4mm greater than the size of the pulmonary autograft. To allow adequate neoaortic growth, this limited the use of the supported Ross to patients older than 10-12 years. The comparison between average discharge and follow-up echo measurements are in Figure 3. There were no deaths during the study period. Five patients required reintervention, but only one of those required an aortic valve replacement.   This study supports the use of supported Ross in select patients above a certain age for aortic valve replacement. The mid-term results are good. The long-term results are obviously needed, but this will take many years to obtain. The size cutoff of a pulmonary autograft of 25 mm is helpful for practitioners seeking to utilize this procedure on their own patients. This can obviously be elucidated clearly preoperatively using CT scan or possibly echocardiography. The major questions that are left after reviewing this paper is are these results durable long-term and are they able to be duplicated in the hands of other surgeons? Certainly, these results are encouraging and should serve as a solid foundation for future studies and the care of young patients with aortic valve disease that requires valve replacement.   Tables and Figures       

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Progression of aortic root dilatation and aortic valve regurgitation after the arterial switch operation

Progression of aortic root dilatation and aortic valve regurgitation after the arterial switch operation. van der Palen RLF, van der Bom T, Dekker A, Tsonaka R, van Geloven N, Kuipers IM, Konings TC, Rammeloo LAJ, Ten Harkel ADJ, Jongbloed MRM, Koolbergen DR, Mulder BJM, Hazekamp MG, Blom NA. Heart. 2019 Nov;105(22):1732-1740. doi: 10.1136/heartjnl-2019-315157. Epub 2019 Jul 10. PMID: 31292191 Free PMC Article Similar Articles Select item 31278142   Take-Home Points: This very large, single institution study with late follow-up of patients after arterial switch operation in the Netherlands continues to expand our understanding of the natural history of this patient population now entering adulthood. Neo-aortic root dimensions increased linearly into adulthood though with minimally changing z-scores. Male gender and complex TGA subtypes were associated with neo-aortic root dilatation whereas previous PA banding and concomitant aortic arch anomalies were not. The incidence of greater-than-moderate aortic regurgitation increased from 5% at 10 years post-ASO to 31% at 25 years and was associated with TGA subtype, ASO after 6 months of age, and increasing aortic diameter. Only 2.9% required surgical reintervention during the study period. Continued serial follow-up is critical for patients following ASO to monitor for neo-aortic root dilatation. Further prospective studies and/or registries are needed to delineate the various factors that are associated with neo-aortic root dilatation particularly when different studies from different centers provide different risk factor profiles.   Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch: In one of the largest retrospective studies with late follow-up after the arterial switch operation (ASO), the Center for Congenital Heart Disease Amsterdam-Leiden in the Netherlands provides long-term follow-up including serial echocardiographic evaluations. The authors included 345 patients who underwent ASO from 1977 until 2015 with at least two subsequent echocardiographic evaluations that included assessment of the neo-aortic root. The longest follow-up period was 39 years with a study mean of 12.2 years. Preoperative balloon atrial septostomy was performed in 52.8% of patients and 5.2% of patients underwent initial PA banding.   In terms of growth of the neo-aortic root (annulus, sinus segment, and sinotubular junction), the authors observed a sharp increase in diameter dimensions during the first year with continued linear enlargement into adulthood (Figure 2A-C). When they converted these dimensions to z-scores, the curves were relatively flat, however (Figure 2D-F). The average diameter progression for the annulus, sinus segment, and sinotubular junction were 0.39 mm/year, 0.63 mm/year, and 0.54 mm/year, respectively. The authors analyzed neo-aortic growth by anatomic subtypes and found that TGA-IVS was associated with the smallest diameter increase whereas patients with DORV-SP-VSD exhibited the highest rate of growth. Male gender was also a risk factor for neo-aortic dilatation. Factors that were associated with the development of aortic regurgitation included TGA subtype, ASO after 6 months of age, and increasing aortic diameter. Despite these trends, only 2.9% of patients required surgical intervention for root dilatation with or without significant aortic regurgitation at a median age of 17.4 years. Interestingly, previous PA banding and the presence of aortic arch anomalies were not risk factors for neo-aortic root dilatation. A bicuspid native pulmonary valve was also not associated with aortic regurgitation.   It remains to be seen whether these trends (including rate of surgical reintervention) will continue as more ASO patients enter adulthood and even late adulthood. If the z-score curves remain flat, can we hope to see a plateau phase in absolute diameter dimension growth? Clearly, ASO patients need life-long surveillance to monitor neo-aortic dimensions and aortic regurgitation. Also needed are multi-center, prospective studies and/or registries that can delineate other management factors (e.g., anti-hypertension management) that contribute to the mixed picture of risk factors associated with neo-aortic root dilatation and the development of aortic regurgitation.     

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Trends in Infant Mortality After TAPVR Repair over 18 Years in Texas and Impact of Hospital Surgical Volume

Trends in Infant Mortality After TAPVR Repair over 18 Years in Texas and Impact of Hospital Surgical Volume. Lahiri S, Wang Y, Caldarone CA, Morris SA. Pediatr Cardiol. 2019 Nov 22. doi: 10.1007/s00246-019-02224-x. [Epub ahead of print] PMID: 31758210 Similar Articles Select Item 31755375   Take Home Points: For uncommon congenital heart defects, centers with a higher surgical volume have been associated with lower surgical mortality rates than centers with lower volume. This review of the Texas Inpatient Use Data File demonstrated an association between higher institutional surgical volume and improved survival after TAPVR repair.   Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch: There have been many studies that support the association with higher surgical volume and improved outcomes. This is especially true in congenital heart surgery where the diversity of lesions is immense and the rarity of specific lesions can be dramatic. One such rare lesion that can have a high mortality is total anomalous pulmonary venous return (TAPVR), which occurs in approximately 1 in 10,000 live births. Repair of isolated TAPVR can be challenging enough, with many patients developing post-repair pulmonary venous stenosis, among other potential complications. Additionally, TAPVR may be associated with other congenital heart defects, single ventricle physiology and heterotaxy syndrome, all of which can increase their postoperative mortality risk.   The authors of this study sought to use the Texas Inpatient Public Use Data File to examine 18 years’ worth of data from state-licensed hospitals that have performed repair of TAPVR. All patients under 1 year old who were hospitalized with the diagnosis of TAPVR were identified from this database. Patient characteristics were identified as were associated congenital heart defects, single ventricle physiology and heterotaxy syndrome. The study examined the overall mortality trend of TAPVR repair in Texas during the study as well as breaking the trend down into separate groups (isolated TAPVR, associated congenital heart defects (CHD), heterotaxy syndrome and single ventricle). The authors also used a multivariable analysis to assess the effect of institutional volume for the procedure with the effects on mortality rate. Their hypothesis was that centers with a higher volume would have a lower mortality.   Out of 7.5 million admissions of children < 1 year old, a total of 971 patients underwent TAPVR repair that met the study requirements. The surgical volume by center (total of 16 centers) is shown in figure 2 below, with a range of 1 repair to 222 repairs during the 18 year period. Overall, mortality for TAPVR repair derived from mixed regression modelling decreased from 15.1% at the start of the study period to 7.6% by the end. Using univariate analysis, the authors found that year of surgery, preterm birth, lower institutional volume, heterotaxy syndrome and presence of additional CHD were associated with higher mortality. With their multivariate analysis, they found that the odds ratio for every increase in 10 patients = 0.93, supporting that higher volume centers had better survival rates.   The study also examined the different subgroups of TAPVR. Repair of isolated TAPVR was the most common surgery with lowest mortality rate (Figure 5). Repair of TAPVR with heterotaxy syndrome and single ventricles are showed in figures 7 and 8, respectively, are shown below. In almost all the multivariable sub-analyses, early year and lower institutional surgical volume were associated with worse outcomes. Of note, the TAPVR/single ventricle group did not have a significant association with lower mortality in later years. I encourage the reader to review the primary study to fully appreciate the scope of data collection and analysis it encompasses.   The study appears to be the first of its kind to demonstrate an association with surgical volume with mortality after TAPVR repair. The authors emphasize that they did not observe a plateau for the mortality rate and that some low- and medium-volume centers had low mortality. The study was restricted to the state of Texas, which is large, but not necessarily reflective of national trends. The emphasis of increased surgical volume on surgical expertise and post-operative care is intrinsic to these findings. The finding of no improved outcomes of single ventricle/TAPVR repairs due to higher institutional volume reflects the high-risk nature of this subgroup of patients. Despite the study analyzing many factors from a “bird’s eye view” of this dataset, there are many details of this lesion that affect outcomes (i.e. type of TAPVR, presence of pulmonary venous obstruction, etc.) that would have made the analysis of these findings all the stronger. It would also be interesting to see how many patients were transferred from another center that performs TAPVR repair to a higher volume center. These types of factors were unavailable as the data is from an administrative database that does not capture as many medical and surgical details of each patient as other databases (i.e. the STS database).   The study is strong, but obviously has limitations. The institutions are not identified and there is no sense of which surgeons are performing the surgeons, so the study does not completely guide practitioners to which institution to direct their TAPVR patients’ care (though, those of us in Texas have some ideas!). Texas has just under 9% of the total population of the United States, and the study acts as a strong sampling of what national trends may be. Of course, the demographics of Texas are not the same as Delaware, and there could be genetic or environmental factors that could affect the prevalence of TAPVR and associated lesions. So it is unclear how easily this data can be applied to other areas. It is retrospective and does not offer sufficient details about all pertinent risk factors, etc. Overall, though, the study offers a fascinating glimpse into the trends in TAPVR repair over time in the second largest state in the county. Tables and Figures           

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Extracorporeal membrane oxygenation use in the first 24 hours following pediatric heart transplantation: Incidence, risk factors, and outcomes

Extracorporeal membrane oxygenation use in the first 24 hours following pediatric heart transplantation: Incidence, risk factors, and outcomes. Godown J, Bearl DW, Thurm C, Hall M, Feingold B, Soslow JH, Mettler BA, Smith AH, Profita EL, Singh TP, Dodd DA. Pediatr Transplant. 2019 Jun;23(4):e13414. doi: 10.1111/petr.13414. Epub 2019 Apr 11. PMID: 30973190 Similar Articles Select Item 30932313   Take-Home Points: This study between linked SRTR and PHIS databases observed that the incidence of severe primary graft dysfunction necessitating ECMO support in pediatric heart transplant recipients was 7.9%. Pre-heart transplant ECMO support was the strongest risk factor for in-hospital mortality in patients with cardiomyopathy or congenital heart disease. Post-transplant in-hospital mortality was most strongly affected by the duration of post-transplant ECMO support, though 90% of patients were decannulated within 7 days. Post-heart transplant patients supported with ECMO who survive to hospital discharge demonstrated similar long-term survival as unsupported patients.   Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch: The authors aimed to combine the SRTR and PHIS databases in a linked manner to evaluate primary graft dysfunction in pediatric heart transplant recipients. Specifically, they used these databases to analyze the incidence of, risk factors for, and outcomes of pediatric heart transplant recipients who developed severe graft dysfunction requiring ECMO support within one day of the heart transplant across multiple participating institutions. Patients <18 years of age who underwent heart transplantation between 2002 and 2016 were evaluated, and ECMO billing codes were used to identify patients who required ECMO support following transplantation. Logistic regression models were used to identify risk factors for needed ECMO support following transplantation and in-hospital mortality.   A total of 2,820 patients were evaluated, and of these, 224 patients (7.9%) required post-transplant ECMO support. The median time on ECMO was 2 days with 90% of patients being decannulated within 7 days. The longest period of support was 50 days.   When comparing all patients by need for post-transplant ECMO support, patients in the ECMO group tended to be younger, have a diagnosis of congenital heart disease (CHD), be on ECMO at the time of transplant, be listed as UNOS status 1A, have a graft ischemic time >4 hours, and have other physiologic impairments (e.g., higher bilirubin level, lower creatinine clearance, and inhaled nitric oxide utilization). Multivariable logistic regression revealed factors independently associated with post-transplant ECMO support including age less <5 years and ECMO support at the time of transplant (additionally VAD support for CHD patients).   The mortality rate for post-transplant ECMO support was 14.3%. Of the 85.3% who were able to be decannulated, 87.4% survived to hospital discharge. The authors further assessed risk factors for hospital mortality, and when duration of ECMO support was excluded from the multivariable logistic regression model, only a graft ischemic time >4 hours was an independent risk factor. When duration of ECMO support was included, independent risk factors for hospital mortality included dialysis and duration of support. A diagnosis of CHD was not a significant risk factor in either case. The need for post-transplant ECMO support portended worse patient survival with 75% of supported patients surviving to hospital discharge compared to 96% of patients in the unsupported. However, the supported patients who survived demonstrated an actuarial survival curve similar to the unsupported group.   The authors elucidate several limitations of the study, particularly in how ECMO patients were identified. Other potential factors that may have affected the observed outcomes but were not able to be assessed include preservation and implantation techniques, complications of ECMO that may have affected mortality, and transplant procedure volume by center.   This large study provides a helpful snapshot of how frequently severe primary graft dysfunction occurs in pediatric patients as well as potential clinical factors that may adversely affect outcomes. The incidence of severe primary graft dysfunction occurs in pediatric patients is not trivial, especially in the youngest patients. This information may be important for counseling families about the risks of heart transplantation in this age group.   

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Use of mechanical valve prostheses in adults with tetralogy of Fallot

Use of mechanical valve prostheses in adults with tetralogy of Fallot. Egbe AC, Miranda WR, Ammash NM, Said SM, Missula VR, Abdelsamid MF, Kothapalli S, Connolly HM. Int J Cardiol. 2019 Feb 16. pii: S0167-5273(18)35800-5. doi: 10.1016/j.ijcard.2019.02.028. [Epub ahead of print] PMID: 30803889 Similar Articles Select Item 30777716   Take Home Points: Patients with Tetralogy of Fallot may need valve replacement during their lifetime, and there is limited data on the results of mechanical valve prostheses in these patients. This retrospective, single-center study evaluated their experience with mechanical valve implantation in all valve positions – not just pulmonary.   Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch: Patients born with Tetralogy of Fallot typically undergo full repair within the first year of life (or within the first few years, from a historical perspective). Many of these patients have residual lesions, especially free pulmonary insufficiency due to transannular patch repair that may require surgery later in life. Currently, it is common practice for patients with free pulmonary regurgitation to undergo a redo sternotomy and implantation of a Bioprosthetic valve into the pulmonary position to preserve right ventricular function and decrease RV dilation. In some centers, surgeons may opt to use mechanical valves for high-risk patients or patients already on anticoagulation. Interestingly, this would lead the reader to believe that this study was about the results of implantation of mechanical valve in the pulmonary position at this center.   But, stop the presses! Though the title seems to infer that is the topic of this study, the authors actually present their results of their cohort of mechanical valve implantation in ALL valve positions, not just the pulmonary position! The authors sought to describe the incidence of mechanical valve related adverse events, reoperation and mortality in all TOF patients with mechanical valve prostheses. The first question that an inquisitive reader might ask is: why are the authors concerned about the results of the mechanical valves in the other positions? There is never a clear answer to this question. However, by using all valve positions, it is clear that the authors can increased the number in this study cohort relative to just studying those with pulmonary valve implantations.   The study reviewed patients from the Mayo Adult Congenital Heart Disease database who were born with Tetralogy of Fallot and underwent mechanical valve implantation in all valve positions between 1990-2017. A total of 29 patients were identified who had a total of 44 valve implantations were identified, with 40 of the valves implanted at Mayo. The median age was 44 years old ± 13 years and the interval between initial TOF repair and first mechanical valve implant was 37 ± 6 years. The valve types were 21 aortic, 6 mitral, 2 tricuspid and 11 pulmonary. Ten of the patients had more than one mechanical valve. It’s fascinating that only 11 of the mechanical valves implanted were in the pulmonary position, given the TOF substrate of the patients. It also indicates that the institutional preference of the Mayo is to place bioprosthetic valves in the pulmonary position. All patients were on Coumadin postoperatively with goal INR ranges specific for the highest risk valve. Figure 1 shows the discharge, 1 year and 5 year average gradients across each of the valve types (excluding tricuspid valve) from the incomplete follow-up of the dataset. The graphs show no significant progression of gradient   The MVRAE rate was 10 total events in 7 patients (24%). There were 4 endocarditis, one valve thrombosis and 5 major bleeds. There were no strokes. Figure 2 shows the freedom from MVRAE events as well as the freedom from reoperation and survival Kaplan Meier curves. There was basically no discussion about the survival curve and re-operation rates, which is bizarre.   The authors admit the limitations of the study include a small sample size, retrospective nature, incomplete follow-up, selection bias and the usual limitations related to this type of study. For some reason, they claim the study is novel because it looks at the mechanical valve implantation into all 4 valve positions instead of just the pulmonary position in TOF patients. This begs the question: what is the unique nature of the aortic, tricuspid and mitral positions in TOF patients as compared to non-TOF patients? As far as I can surmise, the authors saw that the topic had never been published on and decided to add this study to the cumulative knowledge without a significant explanation of how it is useful. I do not see how this study will alter the management of adult TOF patients who need valve surgery, as the same decision-making algorithms apply to these patients before this study was published as after it was.       

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Outcomes After Extracorporeal Cardiopulmonary Resuscitation of Pediatric In-Hospital Cardiac Arrest: A Report From the Get With the Guidelines-Resuscitation and the Extracorporeal Life Support Organization Registries

Outcomes After Extracorporeal Cardiopulmonary Resuscitation of Pediatric In-Hospital Cardiac Arrest: A Report From the Get With the Guidelines-Resuscitation and the Extracorporeal Life Support Organization Registries. Bembea MM, Ng DK, Rizkalla N, Rycus P, Lasa JJ, Dalton H, Topjian AA, Thiagarajan RR, Nadkarni VM, Hunt EA; American Heart Association’s Get With The Guidelines – Resuscitation Investigators. Crit Care Med. 2019 Feb 8. doi: 10.1097/CCM.0000000000003622. [Epub ahead of print] PMID: 30747771 Similar Articles Select Item 30753393   Take-Home Points: Extracorporeal membrane oxygenation (ECMO) in the setting of cardiopulmonary resuscitation is a necessary and useful adjunct salvage therapy, but is characterized by high peri-procedural and in-hospital mortality. Several pre-existing patient conditions, procedural considerations, and ECMO-related complications predispose to an increased risk of mortality, some of which may be improved upon to afford better outcomes into the future.   Commentary from Dr. Michael Ma (Stanford, CA), section editor of Congenital Heart Surgery Journal Watch: Extracorporeal membrane oxygenation (ECMO) cardiopulmonary resuscitation (ECPR) is a critical salvage therapy for patients that fail return of spontaneous circulation (ROSC) despite more conventional Pediatric Advanced Life Support (PALS) algorithms. This study, designed as a multi-center, multi-registry, observational cohort, provides a high-level glimpse at the use of ECPR across the pediatric population (<18 years of age) spanning 32 hospitals over a 15 year period (2000-2014), totaling 593 cases. Registry data from Extracorporeal Life Support Organization (ELSO) and American Heart Association Get With the Guidelines-Resuscitation were linked and de-identified prior to analysis, which was performed using a variety of established statistical methods.   Of these 593 cases, median age 2.9mo, with 70% (414) infants, and 59% (351) were male. 59% (349) were cardiac surgical patients. Median duration of CPR prior to initiation of ECMO was 48 minutes (IQR 28-70 min), and median duration of ECMO support 3.9 days (IQR 2.0-6.7 days). Primary outcome (mortality) was characterized by 40.5% (240) death prior to ECMO decannulation, and 59.4% (352) death prior to hospital discharge. Increasing risk of mortality was associated with non-cardiac diagnosis, prearrest sepsis, respiratory insufficiency, renal insufficiency, longer duration from CPR activation to ECMO initiation, and adverse events reported while on ECMO. In multivariate regression (Figure 3, included below), a noncardiac diagnosis (adjusted OR 1.85 (95% CI 1.19-2.89)) and renal insufficiency (aOR 4.74 (95% CI 12.06-10.9)) were the strongest predictors of death. Each 5 minute incremental delay in the initiation of ECMO increased risk of death by 4% (aOR 1.04 (95% CI 1.01-1.07)). Adverse events on ECMO increased the risk of death, with neurologic and pulmonary complications being the most striking (aOR 2.76 and 2.55 respectively). Multiple adverse events compounded the risk of death further.     These findings corroborate existing, primarily single-center studies that examine ECPR in the pediatric population. The trends discovered are not altogether surprising; patients that require ECPR are at high risk of mortality, and those patients that have pre-existing conditions (i.e. non-cardiac diagnosis, renal insufficiency), peri-procedural difficulty (i.e. time to ECMO support), and post-procedural complications (i.e. adverse events on ECMO), are at the highest risk. The study does add substantially to our specific understanding and historical use of ECPR however, in that it aggregates two large and comprehensive datasets to provide an intimate and quantified understanding of how we, as a community, have performed with this therapy, and how we might go about improving that performance (i.e. patient selection, procedural efficiency, etc.) and counseling patients and families regarding expected prognosis.   

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Homografts versus stentless bioprosthetic valves in the pulmonary position: a multicentre propensity-matched comparison in patients younger than 20 years

Homografts versus stentless bioprosthetic valves in the pulmonary position: a multicentre propensity-matched comparison in patients younger than 20 years. Marathe SP, Bell D, Betts K, Sayed S, Dunne B, Ward C, Whight C, Jalali H, Venugopal P, Andrews D, Alphonso N. Eur J Cardiothorac Surg. 2019 Feb 7. doi: 10.1093/ejcts/ezz021. [Epub ahead of print] PMID: 30753373 Similar Articles Select Item 30729809   Take-Home Points: In this retrospective study of right ventricular outflow tract reconstruction, Freestyle valves and pulmonary homograft exhibited similar freedom from reintervention and structural valve degeneration up to 10 years after placement. Beyond 10 years, the pulmonary homografts exhibited better performance in these categories. However, it is difficult to compare results from this and other small studies that utilize a limited number of available conduits with varying techniques.   Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch: The discussion about which conduit for right ventricular outflow tract reconstruction remains undecided. Evidence continues to slowly grow, but long-term data for the Freestyle porcine aortic valve use for pulmonary valve position are limited. In this study, the group from University of Queensland in Brisbane, Australia, provides a comparison of longer term outcomes of patients <20 years who underwent pulmonary valve replacement (PVR) with either a pulmonary homograft or Freestyle valve.   The authors primarily analyzed freedom from reintervention (surgical and/or catheter-based) and structural valve degeneration (peak gradient greater than 50 mm Hg and/or more that moderate pulmonary regurgitation). A total of 215 patients were included, 163 in the homograft group and 52 in the Freestyle group. The median follow-up was similar for both groups at approximately 8 years. Tetralogy of Fallot was the most common underlying diagnosis in both categories.   Compared to the Freestyle group, patients in the homograft group were younger (14.1 versus 10.2 years) and received conduits with a lower z-score (0.4 versus 1.5). Freedom from reintervention at 5, 10, and 15 years for the homograft group was 96%, 88%, and 81% and for the Freestyle group, 98%, 89%, and 31%. Freedom from structural valve degeneration at 5, 10, and 15 years for the homograft group was 92%, 87%, and 77% and for the Freestyle group, 96%, 80%, and 14%.   The two conduits exhibited overall similar performance up to 10 years after placement then appeared to diverge with more structural valve degeneration and reinterventions in the Freestyle group. A similar pattern was seen when propensity matching was used for 27 pairs of patients. The authors also observed that homografts fared better in an orthotopic position versus heterotopic position and that oversizing Freestyle valves did not affect later performance.   This retrospective, single-center study with mid-term follow-up offers additional insight into how well different conduits perform over time. There are several unanswered questions that could help to understand other implications of these findings:   How did the conduits fail (e.g., due to distal anastomotic stenosis)? How were conduits selected, and was there any change in conduit preference over time? When the conduits did fail, were patients more likely to be able to undergo transcatheter PVR with either conduit type? As with most other studies of this topic, the present study is not comprehensive. Importantly, no bovine jugular venous conduits were used. At our center, we prefer to use bovine jugular venous conduits in patients less than 18 years of age and Freestyle valves in adult patients undergoing PVR. We agree with the authors in that stentless valves generally outperform stented valves in the pulmonary position. Additionally, when it is necessary to use a pulmonary homograft, we prefer those that have been decellularized. In our experience, these have demonstrated improved durability possibly due to a reduced recipient immune response.   This study further demonstrates the considerable inter-institutional practice variation with conduit selection. The debate of the optimal conduit for right ventricular outflow tract remains undecided. Given the nuances of conduit characteristics and implant techniques, it may be difficult to absolutely compare results between institutions. Combining the experience of multiple centers may be necessary to capture a broader estimation of the long-term performance of the available conduits for right ventricular outflow tract reconstruction, however.   

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Current Challenges and Emergent Technologies for Manufacturing Artificial Right Ventricle to Pulmonary Artery (RV-PA) Cardiac Conduits

Current Challenges and Emergent Technologies for Manufacturing Artificial Right Ventricle to Pulmonary Artery (RV-PA) Cardiac Conduits. Manavitehrani I, Ebrahimi P, Yang I, Daly S, Schindeler A, Saxena A, Little DG, Fletcher DF, Dehghani F, Winlaw DS. Cardiovasc Eng Technol. 2019 Feb 14. doi: 10.1007/s13239-019-00406-5. [Epub ahead of print] Review. PMID: 30767113 Similar Articles   Take-Home Points: This article is a helpful review of current challenges and future directions of the development of optimal conduits for right ventricular outflow tract reconstruction.   Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch: Right ventricular outflow tract reconstruction procedures remain one of the most common congenital cardiac surgical procedure performed in children and adults, though the optimal conduit type remains elusive. Manavitehrani and colleagues provide an excellent comprehensive review about this topic, in which they highlight the inherent limitations and challenges of selecting and/or designing conduits. Few clinical data or summaries are provided, though these are beyond the scope of this paper. The authors review the natural characteristics of pulmonary arterial tissue including its biomechanical properties. The evolution of the current landscape of conduit choices is described along with the relevant limitations of current conduit choices including lack of growth potential and biomechanical differences in implanted native and xeno- or allograft material. The authors look ahead at tissue engineering options including scaffold-based processes with various natural and synthetic biomaterials as well as recent advances in electrospinning, 3D printing, and bioprinting. Newer advancements may allow for replacement of the graft material with native tissue, growth with the patient’s somatic size, and improved compliance. However, these process are challenged of incorporating natural cells for tissue differentiation and how to accurately guide cell behavior.  Any of these strategies must provide long-term functional replacement that will be readily functional at the time of implantation. Finally, the authors discuss the role of computational fluid dynamics and modeling in designing and evaluating optimal conduits. Much of the discussion centers around what is currently employed at a few centers for the Fontan procedure, and the extension of this application to RVOT procedures is not difficult to imagine.   

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Midterm outcomes of right ventricular outflow tract reconstruction using the Freestyle xenograft.j

Kuo JA, Hamby T, Munawar MN, Erez E, Tam VKH. Congenit Heart Dis. 2019 Mar 12. doi: 10.1111/chd.12765. [Epub ahead of print] PMID: 30861318 Similar articles Select item 30915321     Take-Home Points:   This is study is a midterm analysis of Freestyle porcine aortic root conduit for RVOT reconstruction in pediatric and adolescent patients. Overall, the Freestyle conduit demonstrated excellent durability up to 10-years, especially in patients >10 years. Risk factors for earlier reintervention included age <10 years, weight <39 kg, smaller body surface area, and valve size 25 mm or less. Orthotopic versus heterotopic position was not a significant factor. Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch:  This report from Cook Children’s Healthcare System in Ft. Worth, Texas, analyzes outcomes of the Freestyle porcine aortic root (Medtronic, Inc., Minneapolis, MN)  for right ventricular outflow tract (RVOT) reconstruction. The authors retrospectively evaluated 163 patients who underwent the procedure between 2002 – 2015 at their institution. Primary outcomes included survival and reintervention rates (surgery, transcatheter valve implantation, balloon valvuloplasty, or bare metal stent placement). The most common primary diagnoses included tetralogy of Fallot (57.1%), pulmonary atresia with ventricular septal defect (14.7%), and truncus arteriosus (10.4%). The median age was 12.2 years (IQR 6.4-16.4) and 40% of patients were <10 years old. The median weight was 39.0 kg (IQR 19.9-59.3). The median follow-up of 5.4 years (IQR 2.9-8), and there were 3 non-cardiac deaths during follow-up.   Thirty-eight (23%) patients required reintervention, and 84% of these were for conduit stenosis. Freedom from reintervention was 93.2% at 5 years and 48.4% at 10 years for the entire group, though these trends were likely heavily weighted by age group. For patients <10 years, the 10-year freedom from reintervention was only 18.0% compared to 82.6% for patients >10 years at time of conduit placement. Risk factors for earlier reintervention included age <10 years, weight <39 kg, smaller body surface area, and valve size 25 mm or less. Orthotopic versus heterotopic position was not a significant factor. No incidences of endocarditis were reported.   As with most reports regarding RVOT reconstruction options, this study faces limitations of being limited to only one institution and without including comparisons with other conduit options.   However, this report is one of the largest experiences with the Freestyle conduit to-date and offers meaningful mid-term follow-up of this conduit. The results of the present study suggest the Freestyle conduit is a durable option for RVOT reconstruction, especially in older pediatric patients.   The Freestyle conduit offers several advantages for RVOT reconstruction including stentless construction, ease of handling, and “off the shelf” availability of a wide range of sizes. In addition, its rigid structure may provide a suitable landing zone for future transcatheter pulmonary valve replacement if adequately sized. Oversizing the conduit is also helpful for accommodating any late anastomotic narrowing. While the technique of implantation (orthotopic versus heterotopic) did not significantly influence rate of reintervention, maintaining laminar flow through the RVOT may be important for long-term durability of any RVOT conduit. Determining which conduits fare better in different age groups remains a key question in congenital cardiac surgery, however.

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Adult Congenital Heart Disease: Current Early Expectations after Cardiac Transplantation.

Riggs KW, Zafar F, Radzi Y, Yu PJ, Bryant R 3rd, Morales DL. Ann Thorac Surg. 2019 Aug 10. pii: S0003-4975(19)31167-1. doi: 10.1016/j.athoracsur.2019.06.067. [Epub ahead of print] PMID: 31408642 Similar articles Select item 31493728     Take-Home Points: This large study of the UNOS database compared early outcomes after cardiac transplantation for patients with and without adult congenital heart disease. Post-transplant outcomes for ACHD patients have improved over the past decade despite ACHD patients having relatively more risk factors than non-ACHD patients. ACHD patients with few risk factors had comparable survival up to 5 years as non-ACHD patients. Further long-term follow-up may determine whether post-transplant survival in ACHD patients surpasses that of nACHD patients given the relatively younger age of ACHD at the time of transplantation. Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch:  The authors sampled the United Network of Organ Sharing (UNOS) database for patients >17 years old with or without adult congenital heart disease (ACHD) who underwent cardiac transplantation between 2000-2018 and primarily evaluated 1-year post-transplant survival.  A possible era effect was analyzed by grouping patients from 2000-2008 (early) and 2009-2018 (late) then comparing the late era with the non-adult congenital heart disease (nACHD) group.   Over 35,000 nACHD patients and over 1,100 ACHD patients were included in the analyses. It is unclear whether ACHD patients who underwent heart-liver transplants were included, but this is typically a very small proportion of heart transplant patients. Late era patients were slightly older (32 versus 37 years), slightly heavier (67.1 versus 71.3 kg), more often sensitized (23% versus 38%), and had longer waitlist times (95 versus 149 days). However, the late era group exhibited better 1-year and overall survival. Compared to nACHD patients, ACHD patients were younger (37 versus 57 years), more likely to be female (38% versus 26%), had fewer ventricular assist devices (14% versus 46%), greater incidence of sensitization 38% versus 29%), and longer waitlist times (149 versus 104 days). Multivariable analysis revealed risk factors for 1-year mortality in ACHD patients included decreased renal function, body mass index >25 kg/m2, total bilirubin >1.2 mg/dL, and graft ischemic time.   When comparing ACHD patients with nACHD patients, ACHD patients who had less than two risk factors had similar 1-year survival as nACHD patients. Moreover, ACHD patients with preserved renal and liver function had similar overall survival as all nACHD patients and possibly trending superior survival beyond 5 years post-transplant (Figure).   These findings demonstrate improved ACHD transplant outcomes over the past decade, which is even more remarkable especially considering the greater association of risk factors during that interval. Unfortunately, granular details such as inotrope use and aspects of other medical management are lacking in this large study. However, it is also interesting that ACHD patients (who are relatively younger) may have better long-term outcomes compared to the older nACHD patients. Hopefully, this finding may help instruct future revisions of UNOS listing criteria for ACHD patients. Finally, the authors postulate that wider utilitization of VADs in ACHD patients may help to mitigate preoperative risk factors and improve post-transplant outcomes.    

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Long-Term Outcomes of Coarctation Repair Through Left Thoracotomy.

Gropler MRF, Marino BS, Carr MR, Russell WW, Gu H, Eltayeb OM, Mongé MC, Backer CL. Ann Thorac Surg. 2019 Jan;107(1):157-164. doi: 10.1016/j.athoracsur.2018.07.027. Epub 2018 Sep 8.   Take Home Points:   Discrete coarctation of the aorta can often be repaired via left thoracotomy and extended end-to-end repair. This retrospective, single-center study evaluated their experience with extended end-to-end repair and showed long-term results with low mortality, low reintervention rates and low incidence of late hypertension. Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch:  Coarctation of the aorta is a relatively common congenital anomaly that, in isolation, can often be repaired with extended end-to-end repair via left thoracotomy and without the need for cardiopulmonary bypass. However, residual coarctation can lead to need for re-intervention and possibly hypertension. The extended end-to-end repair has become the standard surgical preference at the majority of centers, but questions about long-term results remain. Also, there remains controversy over the size cutoff points for when a coarctation can be best managed with an extended end-to-end repair vs. a more invasive arch repair on cardiopulmonary bypass via sternotomy.  The authors of this study sought to evaluate the long-term results of their coarctation repair experience.   The study reviewed patients with isolated coarctation or coarctation with a VSD who underwent surgery between 2000 and 2015. Patients with more complex congenital cardiac malformations were excluded from the study. A total of 251 patients were identified. Of those 186 patients were identified with follow-up (mean 6.1 ± 4.2 years). Table 1 details the preoperative characteristics of the cohort. The primary goals were to evaluate mortality, re-intervention rates and incidence of hypertension. The authors also sought to evaluate the cut-off Z scores for the proximal and descending arch for repair via left thoracotomy.   The surgical technique of repair via left thoracotomy was standard for the institution and was performed in 91% of the 186 patients.  The remaining 9% underwent arch repair via sternotomy. Intraoperative details are listed in Table 2. Interestingly 11% of the coarctation repairs via left thoracotomy were performed with partial cardiopulmonary bypass in this series. The authors describe the “older patients deemed to have collateral circulation (femoral arterial pressure lower than 45 mmHg during test-clamping of the transverse aortic arch)” as needing partial CPB, but it would’ve been helpful to know the ages and weights of these patients to help understand which patients fit in this category.   There were 3 deaths in the follow-up period. Two were non-cardiac in origin and one was a fatal myocardial infarction in a syndromic patient 6 months after repair. The Kaplan-Meier curve for re-intervention is found in Figure 1.  A total of 18 patients had a gradient between upper and lower extremities of > 20 mmHg, but only 4 of them required late re-intervention for recurrent coarctation. All four had transverse aortic arch hypoplasia (Z score < 2) at the time of initial repair. The follow-up for hypertension was the weakest point in the conclusions as it was based on only 18% of the patients in the cohort. So, seemingly, no meaningful conclusions can be made about presence of hypertension long-term.   The authors also evaluated the predictors of surgical approach (sternotomy vs. thoracotomy). Not surprisingly, the presence of a VSD favored sternotomy. Transverse aortic arch hypoplasia did not necessitate repair by sternotomy, however mean proximal arch measurements were smaller in the sternotomy group than in the thoracotomy group (0.35 ± 0.6 cm vs. 0.64 ± 0.3 cm). When the z-scores of proximal transverse arch were examined, the results showed a z-score of -4.98 ± 0.82 for sternotomy group and -2.69 ± 1.84 for the thoracotomy group. The authors performed a logistic regression model for continuous variables to determine cut-points for deciding upon sternotomy vs. thoracotomy. This is illustrated in table 5 and the proximal transverse arch z-score cut-point was -4.1 and for the distal transverse arch it was -2.8. This may be the single-most important findings from this study and compares similarly for cut-off points from other studies. This could help guide surgeons on how small is “too small” for a coarctation repair via thoracotomy.   The limitations of the study were discussed by the authors and included the short “long-term” follow-up period, the incompleteness of follow-up in the cohort, variability of echo findings and the nonrandomized, retrospective nature of the study at a single center. As extended end-to-end repair has become the standard at most institutions, a prospective study of repair via thoracotomy vs. sternotomy is likely impossible. This report adds further evidence that extended end-to-end repair of coarctation is an excellent technique with excellent long term outcomes. The finding of such a low Z-score as a cut-off for the proximal transverse arch should reassure surgeons that performing a repair via thoracotomy is not only feasible, but also has good long term outcomes.

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Repair of total anomalous pulmonary venous connection: risk factors for postoperative obstruction.

White BR, Ho DY, Faerber JA, Katcoff H, Glatz AC, Mascio CE, Stephens P Jr, Cohen MS. Ann Thorac Surg. 2019 Mar 15. pii: S0003-4975(19)30354-6. doi: 10.1016/j.athoracsur.2019.02.017. [Epub ahead of print] PMID: 30885849 Similar articles Select item 30661465   Take Home Points:   Patients born with total anomalous pulmonary venous return have a high risk of recurrent obstruction post-repair though there is still a question of which patients are at highest risk. This retrospective, single-center study evaluated their experience with TAPVR repair and sought to identify risk factors for postoperative pulmonary venous obstruction as well as to try to standardize (and risk stratify) the preoperative echo findings for postoperative obstruction. Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch:  For patients born with total anomalous pulmonary venous return (TAPVR), surgical repair involving creating an unobstructed connection between the venous confluence and the left atrium is the only viable option. Despite an optimal repair, some patients still develop postoperative venous obstruction, which may be untreatable and lead to death. There is no definitive consensus on how to define either pre- or post-operative pulmonary venous obstruction and the risk factors for post-operative obstruction are unclear. The authors of this study sought to better delineate the preoperative and operative risk factors for postoperative obstruction by reviewing a large cohort of TAPVR repairs at their center (Children’s Hospital of Philadelphia). The authors also sought to examine what degree of preoperative obstruction might be predictive of outcome and to create an echo grading system for obstruction.   They looked at all babies undergoing TAPVR repair between January 2006 and October 2017 and found 119 patients. This cohort included patients who had single ventricles and also patients undergoing concurrent cardiac surgical repairs. Notable findings included a whopping 39.5% of patients had single ventricle and 53.8% of all patients had some degree of obstruction. The authors developed definitions for obstruction grade.  “Trivial” obstruction was defined as a mention of obstruction in the echo report but with a Doppler velocity of  < 1.2 m/s. Mild obstruction was defined as a Doppler velocity of ≥ 1.2 m/s but < 2 m/s. Moderate obstruction was defined as Doppler velocity of ≥ 2 m/s, a cath gradient of ≥ 4 mmHg or clinically-noted respiratory distress requiring urgent surgery. Severe obstruction was defined as need for immediate postnatal surgical intervention or stenosis of the vertical vein requiring stenting in cath lab. See Table 1 below for the baseline characteristics of all patients.   The primary endpoint was postoperative obstruction analyzed in a survival framework. Postoperative obstruction was defined as a Doppler velocity of ≥ 1.2 m/s in either the confluence or an individual pulmonary vein or a cath gradient of ≥ 4 mmHg from a pulmonary vein to the atrium. The patients were followed and a flowchart of their results is found in Figure 1. Overall only 21% patients met the criteria for postoperative obstruction, with most of these occurring within the first 6 months after the repair (Figure 2). Interestingly, no postoperative obstruction was identified later than 2.1 years after surgery. The authors also examined if the type of TAPVR affected likelihood of survival without postoperative obstruction and showed the “mixed” type was the highest risk (Figure 3). They also found that heterotaxy syndrome and single ventricles were at higher risk for postoperative obstruction (Figure 4). Finally, in Figure 5, using their preoperative definitions of grades of obstruction, they found using cut-offs of trivial or mild obstruction increased the risk of postoperative obstruction significantly. Other factors such as gestational age, genetic syndrome, type of surgical repair (direct vs. “sutureless”), and whether or not the vertical vein was ligated did not show any statistically significant differences in postoperative obstruction.   This is a thorough review of the recent TAPVR experience at CHOP and contributes very useful information into how to counsel families and manage this challenging anomaly. The development of a preoperative (and postoperative) grading system for pulmonary venous obstruction is certainly helpful and seems to correlate with their outcomes nicely. The findings of association of single ventricle, heterotaxy and mixed-type TAPVR are not newsworthy, but the lack of associations of early age at surgery, genetic syndrome, and surgical technique (among other factors), is helpful. The study suffers from the same limitations as the majority of single-center, retrospective reports; however this was more than just your standard “show-and-tell” retrospective study.  The relatively common (and often lethal) morbidity of postoperative pulmonary vein stenosis has persisted despite advances in diagnosis, surgical technique and post-operative management. This report should help cardiologists and surgeons standardize the risk stratification for patients cursed with this high-risk anatomical arrangement.

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Extracorporeal membrane oxygenation use in the first 24 hours following pediatric heart transplantation: Incidence, risk factors, and outcomes.

Godown J, Bearl DW, Thurm C, Hall M, Feingold B, Soslow JH, Mettler BA, Smith AH, Profita EL, Singh TP, Dodd DA. Pediatr Transplant. 2019 Apr 11:e13414. doi: 10.1111/petr.13414. [Epub ahead of print] PMID: 30973190 Similar articles Select item 30973305   Take Home Points:   Primary graft dysfunction (requiring ECMO) after pediatric heart transplant is not uncommon and can lead to significant morbidity or mortality. This retrospective study was designed using large administrative databases to find the incidence of, risk factors for, and outcomes of primary graft dysfunction and ECMO utilization after heart transplant. The results indicate that primary dysfunction is not rare (7.9% of transplants) and that outcomes are strongly associated with the duration of ECMO.  Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch:  Primary graft dysfunction after heart transplant is often described as a “black box” of unknown etiology that requires extracorporeal membrane oxygenation (ECMO) support to allow the heart to recover, which may not occur. It constitutes 40% of mortality after transplant and often a single factor is not identified as the precipitating cause. The authors of this study sought to examine the incidence of, factors for and outcomes from the use of ECMO within 24 hours after heart transplant in children. They sought to examine two large administrative databases to utilize a unique data linkage to examine their questions.   The SPTR database includes information from every organ transplant since 1987. The PHIS database is an administrative/billing database that captures clinical and resource utilization data, including ICD-9 and -10 codes, from over 50 children’s hospitals. The researchers queried all heart transplants in children under 18 years old between 2002 and 2016 from the linked database and found 2820 patients. Primary graft dysfunction was then examined by using the PHIS to obtain billing codes for ECMO initiation within 24 hours of heart transplant. This was also the method to delineate the duration of ECMO therapy for each of these patients. Baseline demographics and data regarding the heart transplant were obtained. Analyses of this data using multivariate logistic regression models were used to assess risk factors for primary graft dysfunction. The authors also looked at each major transplant group (cardiomyopathy vs. congenital heart disease) to evaluate if there are separate risk factors for each. Outcomes evaluated included ECMO decannulation, re-transplantation and death.   The first key finding from this report is that 7.9% (n=224) of heart transplant recipients required ECMO within the first 24 hours after transplant. The median time on ECMO was 2 days with a maximum duration of 50 days. An evaluation of the multivariable logistic regression of patient demographics and primary graft dysfunction is summarized in table 2. It is not surprising that the authors found that younger patients and patients already on ECMO at time of transplant were independently associated with primary graft dysfunction. The risk factors for ECMO are also evaluated when the transplant recipients are separated into cardiomyopathy vs. congenital heart disease subgroups (Table 3.) Interestingly, only 14.3% (n=32) of the patients placed on ECMO died while on ECMO as seen in Figure 1. Of the 191 patients who were decannulated, 167 (87.4%) survived until discharge. The study also highlights that the survival to discharge decreases as the duration of the ECMO course increases, from 89% survival for 1-3 day ECMO runs to 18.8% survival for more than 10 days. This data is also presented graphically in Figure 2. The risks factors for in-hospital mortality for patients requiring post-transplant ECMO are presented in Table 5. Unsurprisingly, long ischemic times, length of ECMO and post-transplant dialysis were associated with in-hospital mortality. The need for post-transplant ECMO was associated with inferior in-house patient survival compared to those who did not need ECMO. However, for those who survived to discharge after ECMO, there was no long-term difference in survival when compared to those who did not require ECMO (Figures 3 and 4).   This unique method of assessing ECMO utilization in the first 24 hours after transplant by using large administrative databases gives a more thorough understanding of which patients are at risk for the need for post-transplant ECMO and which patients who do need ECMO will survive to discharge. The cynic in me points to the fact that hospitals are not going to forget to bill for ECMO and thus this data should be more complete than other voluntary collaborative databases. Still this data comes from just 28 hospitals and there is obviously much variability among transplant programs’ practices. The findings here will allow transplant programs to help guide their patients’ families into the short- and long-term outcomes from a post-transplant ECMO run. The results seem to be more favorable than expected. It is clear that this study does not allow for a better understanding of what the indication for ECMO was for these patients. And there is obviously the risks of errors and missing information in this data, but the summary of findings should give both practitioners and families hope that the need for post-transplant ECMO support is not a death sentence. Tables and Figures:

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Serial Follow-Up of Two Surgical Strategies for the Repair of Tetralogy of Fallot.

Simon BV, Subramanian S, Swartz MF, Wang H, Atallah-Yunes N, Alfieris GM. Semin Thorac Cardiovasc Surg. 2019 Jan 5. pii: S1043-0679(18)30418-0. doi: 10.1053/j.semtcvs.2019.01.006. [Epub ahead of print] PMID: 30616004 Similar articles Select item 30704940   Take-Home Points:   A limited right ventriculotomy approach during tetralogy of Fallot repair was associated with favorable 10-year event rate, greater exercise capacity at 20 years, and less RV dilation at 30 years compared to a more extensive approach. Overall long-term survival was excellent in both groups, and there was no difference in arrhythmias over time between groups. Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch:  The fate of the right ventricle after tetralogy of Fallot (TOF) repair remains a key question for the management of these patients. Evidence supports utilizing a valve-preserving repair whenever possible, but frequently a hypoplastic pulmonary valve and right ventricular (RV) outflow tract necessitate a transannular repair with patch enlargement.  The group from University of Rochester Medical Center provides further information about the long-term consequences relating to the degree of the transannular incision during TOF repair.   The authors compared outcomes of children who underwent TOF repair with either an extended or limited right ventriculotomy between January 1976 and December 1985. The extended approach was primarily performed between 1976-1981 while the limited approach was primarily utilized between 1982-1985. The extended right ventriculotomy approach included incising the RV infundibulum to the RV mid-body followed by muscle bundle resection and VSD closure. In general, a transannular patch was used if the predicted postoperative RV pressure was greater than 3/4 of the systemic pressure based on catheter or intraoperative assessment. For the limited approach, the VSD was closed transatrially and a 2 cm or less incision made in the RV at the point of maximal obstruction as seen on preoperative catheterization. This opening was then closed with a patch. They excluded patients who underwent pulmonary valve replacement at the initial repair and those who were lost to follow-up after less than 5 years. Primary outcomes included reoperation, arrhythmia, or death. Secondary outcomes included arrhythmias, exercise capacity, and echocardiographic parameters   There were 21 and 17 patients in the extended and limited right ventriculotomy groups, respectively. The median follow-up for the entire group was 30.9 years. Patients in the limited ventriculotomy group were younger (2.7 versus 3.8 years, respectively) and were less likely to undergo transannular patch placement (58.8% versus 85.0%, respectively). The overall survival at 30 years was excellent at 93.6% and was similar between groups. Freedom from reoperation at 10 years was higher for the limited ventriculotomy group (94.1% versus 57.1%). There were no differences in QRS duration or incidence of arrhythmias between groups over time. In the Cox proportional hazards model for 10-year cumulative events, only the limited ventriculotomy approach was associated with a lower event rate.   The authors conclude that the limited ventriculotomy technique was associated with a lower event rate at 10 years, greater, exercise capacity in the second decade (but not the third), and smaller RV end-diastolic diameter Z score at 30 years. The study limitations include its single center nature and the small patient groups. However, this is a truly long-term follow-up period and one of the longest published. In essence, the authors evaluated a generation of patients, many of whom have proceeded with at least one pulmonary valve replacement. It is possible that the surgical approach and patient selection changed over time, and it is unclear Questions as to what is an acceptable residual RVOT gradient at the time of repair. Most TOF patients do not need routine preoperative catheterization, and using the authors’ method of comparing PA pressure to systemic pressure may not be practical in all cases. However, it is reasonable to conclude that limiting the transannular incision may be beneficial long-term.

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Impact of Regional Cerebral Perfusion on Outcomes Among Neonates Undergoing Norwood Operation.

Migally K, Rettiganti M, Gossett JM, Reemtsen B, Gupta P. World J Pediatr Congenit Heart Surg. 2019 May;10(3):261-267. doi: 10.1177/2150135118825274. PMID: 31084315 Similar articles Select item 31084314   Take Home Points: The use of regional cerebral perfusion (RCP) during the Norwood surgery is a technique utilized by many (but not all) surgeons to improve cerebral protection to the neonatal brain during aortic arch reconstruction. This study utilized the public use data from the Pediatric Heart Network Single Ventricle Reconstruction trial to evaluate outcomes whether RCP affected outcomes such as mortality, need for heart transplant, prolonged mechanical ventilation and prolonged hospital stay … but not neurologic outcomes. And the dataset used to come to these conclusions was not designed to evaluate RCP vs. DHCA.  Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch:  The traditional method of protecting the brain during aortic arch surgery has been deep hypothermic circulatory arrest (DHCA). However, in recent years, an increasing number of surgeons have been using regional cerebral perfusion (or selective antegrade cerebral perfusion) during arch surgeries to maintain some perfusion to the brain for a hypothetical improvement in outcomes, especially neurologic outcomes. The Single Ventricle Trial was conducted between 2005 and 2009 at 15 North American centers and was designed as a randomized controlled trial to evaluate modified BT shunts and Sano RV-PA conduits during the Norwood procedure for hypoplastic left heart syndrome.  The dataset from this study was made available for public use in 2013.   This present study was designed by researchers at the University of Arkansas to use this public dataset to evaluate whether patients who received RCP (as opposed to DHCA) at the time of their Norwood had different outcomes with respect to mortality, need for heart transplant, prolonged mechanical ventilation and prolonged hospital stay. These endpoints were evaluated between the two study groups (RCP vs. DHCA) from the initial study (Sano vs. BT shunt). However, the study was not designed to evaluate the difference between DHCA and RCP. This is clear because the evaluation of neurologic outcomes is not one of the primary endpoints of this present study (even though it is the main reason why surgeons may employ RCP vs. DHCA). The researchers also examined a host of other factors to determine the need for heart transplant or mortality, but only a few were statistically significant and those that were significant were not surprising. (Table 1).   Of the 549 patients qualified for inclusion in this study, 252 (45.9%) received RCP during their Norwood procedure. The information in Table 2 shows the variables that were related to the use of RCP that were statistically significant. Essentially, RCP was associated with longer CPB times, increased use of ultrafiltration and open chest after Norwood. It also showed that surgeons performing ≤ 10 Norwoods/year were more likely to use RCP.  Table 3 shows that these longer surgeries and the use of RCP had no effect on the study outcomes, which is the key point of this study. Figure 2 depicts the increasing effect no mortality of increasing RCP and DHCA times.   What do we learn from this study?  Well, when it comes to evaluating the principal difference between why a surgeon uses RCP and DHCA, which is neurologic outcomes, we learn nothing.  The “secondary” outcomes that are evaluated here show there are no differences between the use of RCP and DHCA from this dataset. The authors also emphasized the finding that surgeons who do fewer Norwoods are more likely to perform RCP during their surgeries. As a surgeon, this makes perfect sense since the cases (should) take you longer if you do fewer of them. Also surgeons that are performing the bulk of the Norwood procedure at any center in this study are likely to be at a more senior level in their career, faster, and (in general) used to performing the surgery under DHCA.  So this finding is little more than an unsurprising footnote. The inherent bias of some (especially experienced) surgeons to use DHCA vs. RCP really undermines the entire point of this study. There is no good way to parse out this factor from this dataset.   Is there really a difference in the selected outcomes in this study?  No, not from what this dataset says. But the study was not randomized (or even powered) to look at RCP vs. DHCA, so it is unclear how valid the researchers’ findings are.  And, again, there is zero mention of neurologic outcomes (not even stroke) which also is a major flaw. To break the results down to their core, we learn that during that 4 year period of the SVR trial there was no major difference between the chosen outcomes between Norwoods with RCP vs DHCA at these 15 institutions. And this fact may, or may not, be applicable to present-day practices. As usual, a better trial is needed to answer this question. Tables and Figures:  

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Outcomes of Bioprosthetic Valves in the Pulmonary Position in Adults with Congenital Heart Disease.

Egbe AC, Connolly HM, Miranda WR, Dearani JA, Schaff HV. Ann Thorac Surg. 2019 Jul 16. pii: S0003-4975(19)31033-1. doi: 10.1016/j.athoracsur.2019.05.068. [Epub ahead of print] PMID: 31323213 Similar articles Select item 31313513     Take-Home Points: This large single-institution study with longer term follow-up evaluated the durability of bioprosthetic pulmonary valve replacement in adult patients as well as risk factors for prosthetic valve dysfunction. Factors associated with prosthetic valve dysfunction included prior history of atrial fibrillation and greater than moderate right ventricular dysfunction. The use of vitamin K antagonists at the time of hospital discharge was associated with lower risk of prosthetic valve dysfunction.  Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch:  This retrospective review adult patients who underwent surgical bioprosthetic pulmonary valve repair over an 18-year period at the Mayo Clinic evaluated at prosthetic valve dysfunction not simply as occurrences of reintervention but other hemodynamic parameters to more accurately gauge prosthetic pulmonary valve longevity. The authors defined prosthetic valve dysfunction as a peak valve velocity of >4 m/sec and/or severe pulmonary regurgitation. In all, 573 patients met inclusion criteria with a mean age 32 years at the time of valve replacement. Pericardial prostheses were most commonly used, and all valve types and parameters are listed in Table 2. Patients were followed for a mean 16.8 +/- 4.2 years.   Subsequent reintervention occurred in 201 patients (35% total; 192 surgical and 9 transcatheter valve replacement). Of these, 48 (9%) required another intervention. In all, 807 bioprosthetic pulmonary valves were implanted in 573 patients. The overall freedom from reintervention at 10 and 15 years was 83% and 61%, respectively. When looking at hemodynamic parameters, the average time-to-prosthetic valve dysfunction was 12.6 years with an incidence at 10 and 15 years of 27% and 48%, respectively. In the multivariable risk factor model, factors associated with prosthetic valve dysfunction included history of atrial fibrillation and greater than moderate right ventricular dysfunction. The use of vitamin K antagonists at the time of hospital discharge was associated with lower risk of prosthetic valve dysfunction.   This study with excellent long-term follow-up offers significant insight into the current phase of care of adult congenital heart disease patients who require ongoing right ventricular outflow tract reintervention. These data show that prosthetic valve dysfunction starts to become a significant factor 10-15 years after valve replacement. Patients with more significant right heart dysfunction may be at risk for earlier development of prosthetic valve dysfunction, though the reasons for this are not clarified in this study. Interestingly, the use of vitamin K antagonists may be helpful in improving valve durability like bioprosthetic valves inserted in left heart positions. It is unclear for how long this treatment occurred and whether patients were also treated with aspirin. Importantly, no cases of endocarditis are reported in this study.   This large series spans almost 20 years, and it is possible changes in surgical techniques and prosthetic materials may have affected prosthetic valve durability over the course of the study. Additional information about concomitant cardiac procedures at the time of pulmonary valve replacement (e.g., MAZE procedure, pulmonary arterioplasty, etc.) may be helpful for better understanding this patient group and other risks for later valve dysfunction. One significant omission may be the use of stentless porcine aortic root grafts, which is the preferred prosthesis for pulmonary valve replacement in adults at our institution. This highlights one of the major limitations of a single institution study as well as the need for more collaborative research efforts.        

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Surgery for anomalous aortic origin of coronary arteries: a multicentre study from the European Congenital Heart Surgeons Association†.

Padalino MA, Franchetti N, Hazekamp M, Sojak V, Carrel T, Frigiola A, Lo Rito M, Horer J, Roussin R, Cleuziou J, Meyns B, Fragata J, Telles H, Polimenakos AC, Francois K, Veshti A, Salminen J, Rocafort AG, Nosal M, Vedovelli L, Guariento A, Vida VL, Sarris GE, Boccuzzo G, Stellin G. Eur J Cardiothorac Surg. 2019 Mar 20. pii: ezz080. doi: 10.1093/ejcts/ezz080. [Epub ahead of print] PMID: 30897195 Similar articles Select item 30893567   Take-Home Points:   AAOCA can be clinically very significant, resulting in sudden cardiac death and/or acute profound ventricular dysfunction. The management of clinically significant AAOCA involves surgical correction by a number of techniques that are generally very safe, with little morbidity and mortality. In the largest surgical AAOCA series published to date, operative and long-term mortality was 1.3% and 2.2% respectively. Event-free survival was estimated to 74.6% at 20-25 year follow-up. Most patients remained in excellent functional status, and a small subset continued to have poorly-defined chest pain after surgical repair.  Commentary from Dr. Michael Ma (Stanford, CA), section editor of Congenital Heart Surgery Journal Watch:  This multi-center retrospective review comprises the largest surgical AAOCA series to date, and demonstrates immediate and long-term results after surgical management for this condition. While it does not specifically try to answer controversies around appropriate patient selection, it does conclude that surgical therapy is very safe with little long-term morbidity or mortality.   156 patients with isolated AAOCA from 1991-2016 were studied. Generally, indications for intervention included all AAOLCA (anomalous left), symptomatic AAORCA (anomalous right), and asymptomatic AAORCA with preoperative testing suggestive of inducible ischemia. 85.9% of the cohort was considered symptomatic. Coronary unroofing (56.4%), coronary reimplantation (19.2%), and coronary artery bypass grafting (CABG) (15.4%) were most commonly employed. Two (1.3%) patients died in the immediate post-operative period; both patients presented with low cardiac output prior to surgical intervention and ultimately succumbed to complications of ventricular dysfunction. 14 (9%) patients suffered post-operative morbidity, including low cardiac output syndrome in nine with six of those requiring mechanical circulatory support, early re-intervention in seven, and mild-moderate aortic valve regurgitation (after unroofing) in two (1.3%).   At late follow-up (median two years), three (2.2%) deaths occurred in septuagenarians. Long-term morbidity included three (2.3%) operative re-interventions (aortic valve replacement, followed by pacemaker in the same patient, ascending aortic replacement with myocardial bridge unroofing in a separate patient), five (3.7%) non-operative re-interventions (three coronary stents, one electrophysiologic ablation, one internal cardioverter-defibrillator). 91.2% of late survivors were in NYHA Class I or II. 14.2% of patients continued to have symptoms, primarily undefined chest pain, with only  one correlated to an ongoing positive cardiac stress test. These findings corroborate existing, primarily single-center studies that examine the overall safety of surgery for AAOCA in a population of patients that meet consensus criteria for intervention. Despite generally favorable results, immediate and long-term complications and death did occur, and were not statistically linked to one particular subset of patients or procedure choice. Importantly, these findings add yet an additional data point for consideration in the more controversial management question of what, if any, therapies to offer the asymptomatic patient who is diagnosed with AAOCA through incidental imaging.  

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Primary Transplantation for Congenital Heart Disease in the Neonatal Period: Long-term Outcomes

Primary Transplantation for Congenital Heart Disease in the Neonatal Period: Long-term Outcomes. John MM, Razzouk AJ, Chinnock RE, Bock MJ, Kuhn MA, Martens TP, Bailey LL. Ann Thorac Surg. 2019 Jul 27. pii: S0003-4975(19)31062-8. doi: 10.1016/j.athoracsur.2019.06.022. [Epub ahead of print] PMID: 31362016 Similar articles Select item 31257331   Take Home Points: Primary cardiac transplantation of neonates is an alternative treatment strategy to palliative reconstruction of uncorrectable congenital heart disease. This authors reviewed their single-institution experience with primary cardiac transplantation of neonates between 1985 and 2017 and found their results to be durable with acceptable long-term survival. Commentary from Dr. Timothy Pirolli (Dallas), section editor of Congenital Heart Surgery Journal Watch:  Until the early 1980s with the advent of the Norwood palliation, hypoplastic left heart syndrome was uniformly fatal. During this period, primary cardiac transplantation for neonates (and older children) was pioneered as well. As outcomes for the Norwood procedure improved in the 1990s, surgeons focused on that palliation pathway rather than primary transplant. However, there is data that shows that long-term survival for neonates undergoing primary cardiac transplant is excellent, and longer than for other age groups.  This study was designed to examine the outcomes from the largest single-center series of primary neonatal heart transplants in the world at Loma Linda.   The authors reviewed their database for neonatal heart transplants between November 1985 and December 2017. They looked not only at pre- and post-operative risk factors, but also at long-term outcomes and growth/neurologic development. There was no comparison group for patients of the same age range with uncorrectable congenital heart disease who received either no surgery or palliative procedures (including the Norwood procedure). The authors described the evolution of surgical technique, immunosuppression protocols, and post-transplant surveillance.   There were 104 neonates during the study period who underwent primary cardiac transplant, of which 88 of those occurred between 1985 and 1995 (Figure 1). This was attributed to the emerging acceptance of the Norwood procedure as a primary palliative procedure for HLHS/variants after this time (as well as a sharp decline in available donors). HLHS/variants comprised 77.8% of primary diagnoses in this cohort. The diagnoses were made in utero in 35.5% of patients and 20 patients were actually listed for transplant prenatally! Median weight at transplant was 3.3 kg and median age was 17 days.  An array of recipient and donor characteristics were assessed. Of note, a donor-to-recipient ratio of > 2 was found in 37.5% of transplants. Operative details revealed a 5.7% perioperative mortality of 5.7% with a median duration of follow-up of 19.9 years. Of the 104 patients, 62 are still alive at the time of the publication (Figure 2) with good 10-, 20- and 25-year survival rates.   The authors also examined the development of coronary artery vasculopathy (Figure 3) and post-transplant lymphoproliferative disease. A total of 16 patients required re-transplant (Figure 5). Of the 42 patients who died, 12 died from rejection and 6 from infection. Other notable post-operative complications are catalogued in the paper and none are unusual or occur at abnormally high frequency. The majority of surviving patients (81.2%) were of appropriate height and weight for age and almost 70% were at an appropriate education level or gainfully employed. A multivariate analysis for risk factors affecting survival showed that Glomerular Filtration Rate and the diagnosis of coronary artery vasculopathy were the main variables to have an effect on mortality.   The authors’ commentary was helpful in understanding the evolution of primary neonatal cardiac transplant at Loma Linda. Their conclusion of the therapy as durable with a minimal need for re-intervention certainly seems like a logical conclusion. So why is it not more prevalent at their institution and others?  The small donor pool is part of the answer. Their discussion about the causes of and potential solutions to this issue have been discussed in prior publications, but their points resonate louder with these very good results from their transplant experience. The ideas of ABO-incompatible transplant and over-sizing donor grafts are utilized at our institution and others. The idea of utilizing donors with anencephaly was also discussed as was the associated ethical and PR-related issues surrounding it.   So these results are very good, but are they reproducible? We may never know unless there is a dramatic shift back towards utilizing cardiac transplant as a primary therapy for neonates. But who are the patients that were not offered transplant for whatever reasons?  What was the waitlist mortality? Are these results as good as they are because only the “best” candidates with uncorrectable heart disease were offered transplant? It is certainly an impressive series with excellent follow-up… but the skeptic may suggest the findings, though imperfect, are almost “too good” for that first decade of neonatal transplant.   But maybe the skeptics are wrong. Maybe we over-rely on the Norwood procedure and even mechanical circulatory support to palliate patients that may be better off with a primary cardiac transplantation. One idea that was rarely utilized was listing for transplant for a fetus, which was stopped in 2016. According to a 2014 paper by Thrush and Hoffman in the Journal of Thoracic Disease, PHTS registry data indicated fetal listing in 46 of the 4,365 (1%) patients between 1993 and 2009.  But what happens if expecting parents of a fetus with HLHS finds this paper from Loma Linda and compares it to published results from the Norwood palliation and request a primary transplant from their cardiologist/surgeon? These are the interesting questions that may result from this type of data.   Tables and Figures Figure 1: Neonatal Heart Transplantation Figure 2: Overall Survival Figure 3: Freedom from Cardiac Allograft Vasculopathy         Figure 5: Freedom from Re-transplantation

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Serial assessment of postoperative ventricular mechanics in young children with tetralogy of Fallot: Comparison of transannular patch and valve-sparing repair

Annavajjhala V, Punn R, Tacy TA, Hanley FL, McElhinney DB. Congenit Heart Dis. 2019 Apr 15. doi: 10.1111/chd.12772. [Epub ahead of print] PMID: 30989806 Similar articles Select item 30732866   Take-Home Points: This study utilized certain echocardiographic parameters to assess ventricular function and mechanics following tetralogy of Fallot repair with either a transannular patch or valve-preserving technique with follow-up of up to 7 years. Global longitudinal strain and RV:LV basal dimension ratio parameters may be helpful in following ventricular dimensions and mechanics, especially when other typical parameters are within normal limits. Early ventricular dilatation was observed after both repairs though was more significant after transannular patch repair. However, ventricular dilatation improved over time but did not reach normal parameters. Significant pulmonary regurgitation was associated with worse LV global longitudinal strain and was more pronounced after transannular patch repair across all time points. How these parameters may be practically applied to clinical decision-making (i.e., timing of pulmonary valve replacement) remains to be seen.   Commentary from Dr. Jeremy Herrmann (Indianapolis), section editor of Congenital Heart Surgery Journal Watch:  The authors evaluated various right ventricular mechanics following tetralogy of Fallot (TOF) repair using echocardiographic methods with the aim of trying to understand the trajectory of ventricular function and mechanics over time beyond the early period after repair. Specifically, they compared RV parameters for patients who underwent a valve-sparing (VS) versus transannular patch (TAP) repair of TOF. Patients who underwent complete TOF repair <12 years at their center between January 2002 and September 2015 were included. Overall, 150 echo studies for 42 patients were analyzed. Of these patients, 45% underwent VS repair and 55% underwent TAP repair at a mean age of 2.1 months. Concomitant RVOT procedures during VS repair included infundibular myectomy 89%), pulmonary valvotomy 42%, patch augmentation of the main pulmonary artery (37%), and a subvalvar RVOT patch (21%). Moderate or severe PR was present in nearly all TAP patients across all time points, though the proportion of patients with severe PR following VS repair increased over time. There was gradual RV dilation over time in the TAP group but not the VS group. LV EF was lower in the VS group early but improved over time. LV and RV dysfunction were present postoperatively in both groups and did not fully recover during the study period. Significant PR was associated with lower LV global longitudinal strain. A total of 10 patients underwent surgical or transcatheter reintervention (8 in the TAP group, 2 in the VS group). Of these, 7 involved surgical PVR and 1 transcatheter PVR.​ However, it is not clear how the echocardiographic parameters utilized in the study were applied to these specific patients. The authors conclude that ventricular function tends to improve over time after TOF repair. TAP repair tends to be associated with more RV dilatation, and global longitudinal strain correlated inversely with the presence of pulmonary regurgitation. Importantly, ventricular parameters improved over time, but did not reach normal limits. Certain parameters such as and RV:LV basal dimension ratio may provide objective data for following patients, especially before LV function is impacted. How these parameters may factor into further decision-making (i.e., timing of pulmonary valve replacement), is not yet clear. Perhaps more importantly, long-term trends in these parameters may help clinicians weigh initial surgical options for TOF repair.  

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Outcomes After Extracorporeal Cardiopulmonary Resuscitation of Pediatric In-Hospital Cardiac Arrest: A Report From the Get With the Guidelines-Resuscitation and the Extracorporeal Life Support Organization Registries

Outcomes After Extracorporeal Cardiopulmonary Resuscitation of Pediatric In-Hospital Cardiac Arrest: A Report From the Get With the Guidelines-Resuscitation and the Extracorporeal Life Support Organization Registries. Bembea MM, Ng DK, Rizkalla N, Rycus P, Lasa JJ,...

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Classification scheme for ductal morphology in cyanotic patients with ductal dependent pulmonary blood flow and association with outcomes of patent ductus arteriosus stenting

Classification scheme for ductal morphology in cyanotic patients with ductal dependent pulmonary blood flow and association with outcomes of patent ductus arteriosus stenting. Qureshi AM, Goldstein BH, Glatz AC, Agrawal H, Aggarwal V, Ligon RA, McCracken C, McDonnell...

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