CONGRESS ABSTRACT

A 69-year-old man with a history of hypercholesterolemia and frequent episodes of supraventricular extrasystoles and paroxysmal supraventricular tachycardia (PSVT), with echocardiographic evidence of dilation of the right heart chambers without an apparent cause. In 2016, the echocardiogram showed right ventricular dilation, mild tricuspid regurgitation, and pulmonary artery systolic pressure (PAPs) of 50 mmHg. In the same year, due to persistent PSVT episodes, he underwent SEF and slow nodal pathway ablation, with concurrent MRI findings suggestive of minor criteria for right ventricular arrhythmogenic cardiomyopathy, although alternative causes could not be excluded. In 2019, he underwent cardiac catheterization, which diagnosed probable abnormal pulmonary venous return, and was advised to undergo chest angio-CT to study venous returns. As a result, in 2022, he underwent chest/pulmonary aorta angio-CT, which revealed multiple abnormal partial pulmonary venous returns, affecting the entire return of the right upper lung lobe and part of the right middle lobe, at various levels in the superior vena cava. A large superior sinus venosus interatrial defect (ASD) was identified between the outflow of the superior vena cava and the right superior pulmonary vein, draining the remaining part of the middle lobe and likely some branches of the right lower lobe. Therefore the diagnosis of right ventricular arrhythmogenic cardiomyopathy was excluded. In 2023, he was visited for the first time at our center where the echocardiogram confirmed a large sinus venosus-type interatrial defect, partial abnormal pulmonary venous return into the superior vena cava, severe dilation of the right heart chambers, and normal systolic pressure in the right ventricle. The same year, coronary angiography was performed, with the following result: "Critical stenosis at the ostial segment of the left anterior descending artery (LAD), followed by severe stenosis in series in the middle segment and first diagonal branch; atherosclerotic coronary artery with subocclusion of the postero-lateral branch ; right coronary artery with dilatative atherosclerosis and moderate stenosis in the middle-distal segment; critical stenosis of the posterior descending branch." Therefore, following a multidisciplinary discussion, the patient underwent surgery to correct the partial abnormal venous return, close the interatrial septal defect (IASD), and perform a concurrent aortic-coronary bypass.