Persistent left superior vena cava with absent right superior vena cava and discrete subaortic stenosis diagnosed in a patient with sick sinus syndrome: a case report and brief review of the literature

Figure S1: Doppler evaluation of the subaortic obstruction. Figure S2: Fluoroscopic image of the final trajectory of the pacemaker lead. Video S1: Transthoracic echocardiography, apical 3-chamber view, showing the subaortic membrane and the dilated coronary sinus. Video S2: Transthoracic echocardiography, apical 3-chamber view, showing the mild aortic regurgitation. Video S3: Transthoracic echocardiography, apical 4-chamber view, showing the cardiac cavities with normal dimensions, and the left ventricle with normal systolic function. Video S4: Transesophageal echocardiography view showing the subaortic membrane and the systolic fluttering of the aortic valve. Video S5: Venography performed from left subclavian access, demonstrating a left SVC draining in the right atrium via the coronary sinus, but without the possibility to clearly assess the status of the right SVC. Video S6: Venography performed from the right subclavian access demonstrating the absence of the SVC on the right side.