Right Ventricular Coiling to Limit Right Ventricle to Coronary Artery Connections in Pulmonary Atresia with Intact Ventricular Septum following Stage 2 Palliation

Objectives: The management of patients with pulmonary atresia and intact ventricular septum (PA-IVS) who present right ventricle to coronary artery connections (RV-CAC) has not been settled. We describe partial RV coiling to prevent the coronary arteries from high-pressure retrograde flow, which usually results in progressive intimal hyperplasia and potential myocardial damage.

Methods: We describe a boy with PA-IVS and a tripartite hypoplastic RV with suprasystemic pressure. In the neonatal period, angiography had revealed concomitant coronary flow between the RV and native aortic root via non-obstructed coronary arteries, respectively. Initial therapy consisted of stenting the arterial duct followed by a stage 2 Glenn procedure at the age of 5 months. On follow-up, selective coronary angiography showed a weakening tendency for the RV to perfuse toward the right coronary artery, but persistent strong to-and-fro flow between the RV´s apical cavity and entire left coronary artery system (LCA). At two years of age, he underwent antegrade test-occlusion of the apical RV via a 4 Fr wedge-catheter: the intended RV-CAC pressure drop was clinically well tolerated under general anesthesia, while aortal diastolic pressure provided adequate LCA perfusion on selective angiography. Two tightly packed 8 mm × 60 cm soft coils were then delivered through a microcatheter (supported by a 4 Fr diagnostic catheter) and successfully implanted for partial RV occlusion.

Results: The angiography of the RV´s apical cavity's coiling showed no relevant retrograde flow via the RV-CACs, whereas LCA angiography revealed improved antegrade diastolic imaging. Anticoagulation with heparin was maintained for 48 hours and replaced by oral aspirin. Repeated electrocardiographs documented no ST-segment alterations. Local wall motion abnormalities were ruled out by echocardiography. Stage 3 palliation proceeded uneventfully two months later.

Conclusion: RV-CAC complicates the treatment of patients with PA-IVS, as their spontaneous evolution and impact on patient outcome are unpredictable. Coronary lesions induced by retrograde high-pressure perfusion are known to be risk factors for premature atherosclerotic lesions and aneurysmal dilatation. Coil-occlusion of the right ventricle may be a sensible option to limit RV-CAC flow. Antegrade transvenous approach via the tricuspid valve may be considered before final stage 3 palliation in this setting.