Possible link between right ventricular coronary sinusoids and noncompaction sinusoids in pulmonary atresia with intact ventricular septum patients that later develop left ventricular noncompaction.

Patients who have pulmonary atresia with intact ventricular septum have been shown to have a number of various myocardium anomalies like ischemia, fibrosis, infarction, rupture, disarray, spongious myocardium and ventricular endocardial fibroelastosis. Multiple connections have been found between right ventricular myocardial sinusoids and small branches of intramural coronary arteries. Noncompation of ventricular myocardium has been shown to be the result of myocardial ischemia or excessive pressure preventing the reduction of embryonic sinusoids. The persistence of intertrabecular recesses that are connected to both the ventricular cavity and coronary circulation is the result of this process. In this text, we describe a PA-IVS patient who underwent patent ductus arteriosus stenting and pulmonary valve perforation to create antegrade flow and later developed left ventricular noncompaction. We posit that there is a connection between right ventricular coronary sinusoids and noncompaction sinusoids. As our patient's RV outflow tract stenosis and RV pressure increased, the coronary circulation connected to coronary sinuses became sufficient and LV function improved, which further supports our hypothesis.