Fig. 1

a Transthoracic echocardiography on short-axis view demonstrates an unusual, tubular-like structure inside the interventricular septum (arrows). b to d Transesophageal echocardiography reveals markedly dilated right coronary artery (RCA) arising from the right aortic sinus (arrow, b). There was a tortuous, abnormal vessel located adjacent to main pulmonary artery (MPA) emptying into the posteromedial aspect of the MPA with accelerated flow across the stenotic ostium (asterisk, c). Severe mitral regurgitation from posterior mitral leaflet restriction in combination with mitral annular dilatation is observed (d). LV; left ventricle, RV; right ventricle, LA; left atrium, Ao; ascending aorta