Adult Congenital Heart Disease

Magnetic resonance lymphangiography in post-Fontan palliation patients with MR non-conditional cardiac electronic devices: An institutional experience. Ramirez-Suarez KI, Otero HJ, Biko DM, Dori Y, Smith CL, Feudtner C, White AM.Clin Imaging. 2022 Jun;86:43-52. doi: 10.1016/j.clinimag.2022.02.016. Epub 2022 Feb 23.PMID: 35334301   Take Home Points: The use of MRI, when no comparable alternative diagnostic imaging modality exist, as in the case of lymphatic system imaging, can be used with no major adverse effects in patients with previous epicardial lead Further studies are required in larger cohorts to elucidate safety measures more definitively Commentary from Dr. Blanche Cupido (Cape Town, South Africa), chief section editor of ACHD Journal Watch:   MRI remains the diagnostic modality of choice for the diagnosis of complex lymphatic disorders. Though modern pacemakers are MRI conditional, older pacing devices and other implantable electronic devices have still pose a theoretical restriction to MRI. Epicardial leads, often used in pediatric patients, have traditionally been included in this group with a relative contraindication to MRI due to the theoretical risk of cardiac excitation or thermal injury. The potential harm is attributed to a potential interaction between static and time-varying magnetic fields and device components with the consequences (theoretical) of local tissue damage, ventricular arrhythmias and device malfunction. It is however noted that in clinical practice, the retained leads are short and do not usually form conducting loops.   This study gives the perspective of a single center of 5 patients with complex CHD (post-Fontan) with MRI ‘incompatible’ devices in whom a Dynamic Contrast Enhanced MR Lymphangiography (DCMRL) was performed. The patients underwent DCMRL of the chest, abdomen and pelvis on a 1.5 Tesla Siemens system, under general anaesthesia. All patients had been discussed in an MDT (which included the family and an ethics team) and the risks/benefits explained to the patients.   In all 5 patients, there were no MR safety related adverse events occurring during or following the imaging. This shows potential safety however larger studies would be needed to define the safe practice measures more definitively.   An example of a case is shown below:     

Hypertensive response to exercise in adult patients with repaired aortic coarctation. Meijs TA, Muller SA, Minderhoud SCS, de Winter RJ, Mulder BJM, van Melle JP, Hoendermis ES, van Dijk APJ, Zuithoff NPA, Krings GJ, Doevendans PA, Spiering W, Witsenburg M, Roos-Hesselink JW, van den Bosch AE, Bouma BJ, Voskuil M.Heart. 2022 Jun 24;108(14):1121-1128. doi: 10.1136/heartjnl-2021-320333.PMID: 34987066   Take Home Points: Study involved use of Dutch registry CONCOR Exercise induced hypertension occurred in 44% of patients in this cohort of 675 patients Increased peak exercise systolic blood pressures (> 210 mmHg systolic) was found more often in males, and those with higher resting blood pressures Increased peak exercise systolic blood pressures were found less frequently in patients with bicuspid aortic valve and those following coarctation stenting Increased peak systolic blood pressures predicted higher resting systolic blood pressures in follow up, regardless of resting systolic blood pressure at rest baseline There was no correlation between the occurrence of later cardiovascular events (coronary artery disease, stroke, aortic complications, death) and peak exercise systolic blood pressure Commentary from Dr. Thomas Zellers (Dallas, USA), section editor of Congenital Heart Disease Interventions and ACHD Journal Watch: The authors sought to determine the prevalence of hypertensive response to exercise, identify factors associated with exercise induced hypertension and examine the association between peak exercise systolic blood pressure and resting systolic blood pressure and cardiovascular events at follow up.   The authors used the Dutch national congenital corvitia (CONCOR) registry and examine 920 patients with repaired coarctation. Of these, 675 patients (median age 24 years with range of 16-72 years) underwent exercise testing and follow up at a mean of 10.1 years. Variables examined included resting and stress blood pressure response to exercise, 24 hour ambulatory blood pressure monitoring, echo evaluation for LV hypertrophy and mass, and history of cardiovascular events.   Of the 675 patients, 44% showed a hypertensive response to exercise (systolic BP of > 210 mmHg for men and > 190 mmHg for women). Of the 299 patients with normal resting blood pressure, 35% (n = 104) had hypertensive response to exercise; 50% of those had hypertension at later follow up visits. Of the 376 with resting hypertension, 52% had a hypertensive response to exercise.   In evaluating factors associated with peak exercise systolic blood pressure (SBP), in multivariable analysis, increased resting SBP at baseline was positively correlated with increased peak exercise SBP. Males were also more likely to have elevated peak exercise SBP. Bicuspid aortic valve and coarctation stenting were negatively correlated with peak exercise SBP.   Peak exercise SBP positively predicted office SBP at follow up visit and increased ambulatory blood pressure measurements at follow up; this was independent of resting SBP at baseline. Resting SBP at baseline and the use of antihypertensive medications were also positive predictors of office resting SBP at follow up. When considering only normotensive patients at baseline, peak exercise SBP was also predictive of SBP at office follow up. Given that 35% of normotensive patients, at baseline, had exercise induced hypertension, and that 50% of those had resting hypertension at follow up, it appears that exercise testing, even in normotensive patients, can help predict systolic hypertension at follow up. This is a population that may require an increased frequency in follow up visits to address new onset of hypertension. However, of particular interest, hypertensive response to exercise did not correlate with adverse cardiovascular events.   One must realize that this is a multicenter study using a registry and thus there may be differences in who gets tested, which exercise protocols are used, the use of antihypertensive medications, and the follow up duration. This was a young cohort and thus, the incidence of cardiovascular adverse events may not yet have been realized at follow up.   

Exercise invasive hemodynamics in adults post-Fontan: A novel tool in understanding functional limitation and liver disease. Miranda WR, Jain CC, Borlaug BA, Connolly HM, Egbe AC.J Heart Lung Transplant. 2022 Jun;41(6):704-707. doi: 10.1016/j.healun.2022.02.023. Epub 2022 Mar 9.PMID: 35400586   Take Home Points: In the vast majority of patients with a Fontan circulation, the exercise capacity is significantly reduced due to a multitude of reasons, including impaired stroke volume augmentation, chronotropic incompetence, abnormal oxygen extraction by the muscles, lung disease and others. While obtaining resting hemodynamics in patients with a Fontan circulation is informative and can be helpful in guiding clinical decision making, it provides little information on patient’s hemodynamics during exercise. In this small study, the investigators describe their experience with four exercise hemodynamic studies obtained in patients with a Fontan circulation using supine bicycle. Three of these patients were referred for heart transplantation evaluation and the fourth for assessment of a Fontan pathway obstruction. Commentary from Dr. Yonatan Buber (Seattle, USA), section editor of ACHD Journal Watch:   Table: Clinical and hemodynamic data of the 4 study patients   The authors describe how in each of the cases, the invasively measured hemodynamics assisted in the clinical decision making: in Case 1, a case that was used I a combination with echo, it revealed increase in the wedge pressures due to severe systemic AV valve stenosis and the patient underwent a valvular intervention, in Case 2 it revealed significant diastolic dysfunction and elevation in the wedge pressures, and the patient was referred for a transplant evaluation, in Case 3, no marked abnormalities were found and the patients was referred to a rehab program and prescribed with a PDE-5 inhibitor with marked symptomatic improvement, and in Case 4, a significant increase in the IVC pressures was observed, indicating hemodynamically significant obstruction in the IVC limb, and stenting was undertaken with resolution of the gradient.   Invasive exercise hemodynamics in patients with a Fontan circulation provides an excellent method to evaluate the degree and the potential contributors to exercise intolerance, which as noted above is common in this patient population and may often be multi-factorial. In this brief and very educating communication, the authors provided with three examples of different hemodynamic abnormalities that were almost not apparent at rest and were revealed during exercise, and nicely show how this affected clinical decision making. Importantly, they also provide one example of a relatively benign hemodynamic response to exercise which prompted a referral to cardiac rehabilitation and initiation of a pulmonary vasodilator. No complications were reported in this series. Future directions include the utility of evaluating the effects of pre-exercise NO administration on exercise hemodynamics in Fontan patients, and the potential utility of less invasive methods such as combined cardio-pulmonary exercise testing with echo +/- non-invasive stroke volume assessment to provide with similar results and clinical implications.