Congenital Heart Interventions

Supravalvular and Valvular Pulmonary Stenosis: Predictive Features and Responsiveness to Percutaneous Dilation. Poupart S, Navarro-Castellanos I, Raboisson MJ, Lapierre C, Dery J, Miró J, Dahdah N. Pediatr Cardiol. 2021 Jan 19. doi: 10.1007/s00246-021-02545-w. Online ahead of print. PMID: 33464372   Take Home Points: Echocardiogram has a 56% sensitivity and 82.5% specificity (using angiogram as gold standard) to accurately identify valvular pulmonary stenosis from supra-valvular pulmonary stenosis. Post balloon dilation, patients with supra-valvular pulmonary stenosis had a higher RV-PA gradient as compared to patients with valvular PS. Patients with supra-valvular pulmonary stenosis, balloon-annulus ratio <1.2 or an immediate post intervention gradient 30mmHg had a higher rate of reintervention in the follow up.   Commentary from Dr. Varun Aggarwal (Minneapolis, MN, USA), section editor of Congenital Heart Disease Interventions Journal Watch: Valvar pulmonary stenosis is a common congenital cardiac lesion. Classic valvular pulmonary stenosis with thin doming pulmonary valve leaflets responds very well to balloon pulmonary valvuloplasty. However, patients with coexistent supra-valvular pulmonary stenosis may not respond as well to balloon dilation.   Poupart S et al (1) aimed to evaluate the diagnostic accuracy of echocardiography to differentiate valvular from supravalvular pulmonary stenosis and evaluate the outcomes of percutaneous balloon dilation in supravalvular pulmonary stenosis compared to valvular pulmonary stenosis. They conducted a retrospective analysis of 106 patients from 2006-2017 at a single center in Montreal, Quebec. Both groups had comparable RV-PA gradients prior to intervention (SVPS: 68.04 ± 21.65 vs. VPS: 64.10 ± 14.37; p = 0.312). Using angiogram as a gold standard, the echocardiogram had a low sensitivity of 56% and specificity of 82.5%. A smaller pulmonary artery to pulmonary valve diameter ratio was noted in SVPS as compared to VPS. A pulmonary artery to pulmonary valve annulus ratio (as measured on echocardiogram) of 1.16 had a 64.7% sensitivity and 80.3% specificity to accurately diagnose SVPS.   Post balloon dilation (with similar balloon-annulus ratio in the two groups), the RV-PA gradients were higher in SVPS group as compared to VPS (26.8 ± 12.6 mmHg vs. 11.5 ± 8.5 mmHg; p ≤ 0.001). 71.4% patients with SVPS were deemed resistant to balloon dilation as compared to only 25.9% patients with VPS, p=0.001. Receiver operator curve analysis yielded a cut-off value of 1.20, below which the pulmonary stenosis would likely be resistant to percutaneous angioplasty (AUC = 0.730, p = 0.002).   Figure 1 is a figure from the article (1) demonstrating the follow up echocardiographic gradients in the two groups. The rate of future reinterventions was also higher in the SVPS group (32%) as compared to VPS (6.2%), p<0.05. Despite similar balloon annulus ratios in the two groups, VPS had a higher prevalence of high-grade pulmonary valve insufficiency as compared to SVPS. This study highlights some of the challenges and lower success rate of balloon dilation for SVPS as compared to pure valvular PS. The echocardiographic evaluation prior to the procedure and paying attention to main pulmonary artery diameter to pulmonary valve annulus ratio can help identify these patients more accurately. This information can be helpful in counseling families prior to intervention.   FIGURE 1 Echocardiographic follow-up of RV-PA gradients. Follow-up excludes all data measured after a second intervention, of any kind, on the PV or PA. There was significant decrease in RV-PA gradients in both groups; however, gradients in patients with SVPS were significantly higher than patients with VPS (1).     1. Poupart S, Navarro-Castellanos I, Raboisson MJ, Lapierre C, Dery J, Miró J, et al. Supravalvular and Valvular Pulmonary Stenosis: Predictive Features and Responsiveness to Percutaneous Dilation. Pediatr Cardiol. 2021.   

Risk Factors for Adverse Events in Children with Pulmonary Hypertension Undergoing Cardiac Catheterization. Vaiyani D, Kelleman M, Downey LA, Kanaan U, Petit CJ, Bauser-Heaton H.Pediatr Cardiol. 2021 Jan 29. doi: 10.1007/s00246-020-02535-4. Online ahead of print.PMID: 33512547   Take Home Points: Longer procedure duration and female gender is correlated with increased risk of adverse events in the cardiac catheterization laboratory. Patients with higher pulmonary artery pressure and PVR with certain levels of pulmonary vasoreactivity testing are more likely to have adverse events.   Commentary from Dr. Arash Salavitabar (Ann Arbor, MI, USA), section editor of Congenital Heart Disease Interventions Journal Watch: The authors sought to describe risk factors for adverse events in children with pulmonary arterial hypertension during cardiac catheterization. This was a 5-year single-center, retrospective study that included patients with indexed pulmonary vascular resistance (PVRi) >3 WU*m2, pulmonary artery (PA) pressure 20 mmHg, and PA wedge pressure 15 mmHg. This institution’s protocol for pulmonary vasoreactivity testing was to perform baseline hemodynamics on room air, followed by 100% FiO2, followed by 100% FiO2 and 40ppm inhaled nitric oxide; however, this was not performed in all children. Adverse events were defined as unplanned events related to anesthesia induction or catheterization from which patient harm could have resulted and occurred within 24 hours of cardiac catheterization.   The authors report 198 cardiac catheterizations in 191 patients that met inclusion criteria. There were 33 patients who received transcatheter interventions. There were 28 (14.1%) adverse events (Table 1). There were 6 deaths, with 4 patients developing PH crisis several days following cardiac catheterization.   There were no significant associations between adverse events and patient age, prematurity, Trisomy 21, congenital heart disease, need for baseline respiratory support or history of bronchopulmonary dysplasia, chronic lung disease, use of pulmonary vasodilators, diuretics, vasoactive medications, or use of iNO. Females were more likely to experience an adverse event than males. Risk factors for adverse events are shown in Table 5, notably showing associations between adverse events and procedure duration, PA pressures and PVR on oxygen, as well as PA pressures on oxygen and iNO. These values were not significantly associated at baseline. There was also a more significant change in PA pressures (but not PVR) in response to oxygen and iNO in those patients who had adverse events. The odds of an adverse event increased by 22% for every 15 minutes increase in procedure times. Odds for an adverse event were also increased for every 10 mmHg increase in mPAP while on oxygen (OR 1.58, CI 1.11-2.26) and 61% while on oxygen and iNO (OR 1.61, CI 1.18-2.21). Controlling for procedure time, females had a 388% increase in the odds of experiencing an adverse event when compared to males (OR 3.88, 95% CI; [1.44–10.40], p = 0.007). The patients with adverse events were more likely to have undergone an intervention.     The authors speculated that the association between adverse events and longer procedure times was due to additional opportunities to develop hypoxia and acidosis, thus predisposing to increased PVR. The procedure duration was rightfully identified in this paper as a potentially modifiable risk factor. This paper also is the first to point to female gender as a risk factor, however there were no additional comments made regarding this statistic and its potential cause. This study nicely adds to the existing literature on risk factors for adverse events in this particularly challenging patient population and will allow for better pre-procedural stratification and counseling.