Persistent left superior vena cava: incidence, significance and clinical correlates

Abstract

Persistent left superior vena cava (PLSVC) is a remainder of the physical examination was unremarkcommon anomaly of the systemic venous system [1]. able. Multiple ECGs revealed sinus rhythm, with a It results from persistent patency of the left anterior marked first-degree atrioventricular block and left cardinal vein that drains into a dilated coronary sinus. bundle branch block with a heart rate ranging from Its incidence is reported between 0.3 and 0.5% in the 38 to 78 beats per min. Blood chemistries were general population [2]. Approximately 50–70% of within normal limits. She underwent TEE to rule out these patients are at risk of paradoxical embolism an intracardiac source of embolism and atrial septal because of accompanying lesions (atrial septal defect, defect and to define her cardiac anatomy. This unroofed coronary sinus, or direct communication of showed no evidence of cardiac masses, but did the vein to the left atrium). demonstrate a PLSVC draining into the right atrium This case report illustrates the diagnostic role of via a dilated coronary sinus (Fig. 1). Saline contrast echocardiography in the evaluation and diagnosis of injection was negative for intracardiac shunt. There this relatively rare congenital anomaly. was bi-atrial and bi-ventricular enlargement. The A 60-year-old white woman with a recent history estimated left ventricular ejection fraction was 0.45. of dizziness was referred for evaluation. She had a No segmental wall motion abnormalities were noted. history of paroxysmal atrial fibrillation, left ventricuDuring early embryological development, venous lar dysfunction, and a history of a congenital heart return from the head and arms normally drains to the disease with an atrial septal defect repair. Her vital right atrium via the left and right anterior cardinal signs were stable. Cardiac examination revealed a veins. At approximately 8 weeks gestation, the left grade 2/6 holosystolic murmur at the apex radiating brachiocephalic vein develops as a bridge between to the left axilla. There were no gallops or rubs. The the left and right anterior cardinal veins. The portion splitting of the second heart sound was normal. The of the left anterior cardinal vein caudal to the bridging left brachiocephalic vein normally collapses, then degenerates leaving only the right anterior *Corresponding author. Present address: Division of Cardiology, cardinal vein which becomes the superior vena cava. Marshfield Clinic, 1000 Oak Street, WI 54449, USA. Tel.: 11-715-387If the caudal portion of the left anterior cardinal vein 5301; fax: 11-715-389-4555. E-mail address: takt@mfldclin.edu (T. Tak). remains patent, it becomes a PLSVC which drains