Abstract 12874: Thebesian Veins Are Common and Progress in Adult Patients Late After Fontan Operation

Abstract

Introduction: Thebesian veins (ThVs) are coronary veins that drain directly into the atrial or ventricular chamber. Angiographically detectable ThVs are a rare finding sometimes associated with myocardial ischemia due to coronary steal and volume overload of ventricles in adults. However, there are limited data concerning ThVs in the setting of congenital heart disease. The purpose of this study is to demonstrate presence, character, and changes with growth of ThVs in adult patients late after Fontan operation. Methods: This study is single-center retrospective review of adults with Fontan circulation patients who had undergone cardiac catheterization for routine Fontan surveillance between 2009-2019. We assessed the presence of angiographically detectable ThVs from ascending aortography. After identification of the characteristic cases, we examined the ventricular morphology, the portion of ThVs drainage, and compared with previous findings of angiograms. We also reviewed clinical manifestation and findings of exercise stress ECG of the patients. Pulmonary atresia with intact ventricular septum was excluded because abnormal coronary arterial communications have been well documented in this condition. Results: Among 75 Fontan patients who had undergone catheterization, significant ThVs were observed in a total of 12 cases (16%). There were 6 right-dominant single ventricle, 4 left-dominant single ventricle, and 2 unbalanced two ventricles. In all cases, including left-dominant single ventricle, all ThVs drained into right ventricle cavity, never into left ventricle. The patients who underwent serial catheterizations demonstrated that ThVs dilation and tortuosity progressed over time. Among 6 patients who had underwent exercise stress ECG, only 1 patient showed ST segment depression, however, none had clinical history of chest pain. Conclusions: ThVs are common and progress in adult patients late after Fontan operation. Although the clinical significance of these findings remains uncertain, particular attention should be given to myocardial ischemia and volume overload for the future of adult Fontan patients who have prominent ThVs.