A Case Report about Persistent Left Superior Vena Cava: Is it Always Asymptomatic?

Abstract
A persistent left superior vena cava (PLSVC) is a rare malformation which affects approximately 0.3% - 0.5% of the population and it is presented along with a right-sided superior vena cava in 82.2% of the cases reported [1]. Clinicians diagnose it incidentally by difficulties with pacemaker implantation, central venous catheterization or screening for another etiologies when it is not accompanied by other anomalies it is typically asymptomatic. W. Schummer et al. described the embryogenesis and the anatomic variations of persistent LSVC according to the positioning of a central venous catheter on the chest radiograph: type I, normal; type II, only PLSVC; type IIIa, right and left superior vena cava with connection; type IIIb, right and left superior vena cava without connection [2]. In 92% of individuals with PLSVC, the PLSVC drains into a dilated coronary sinus (CS) and rest 8% drain directly into the left atrium. PLSVC is caused by a failure in the closure of the left anterior cardinal vein during embryogenic development [3]. The coronary sinus (CS) is a vein that transmits venous blood to the right atrium though atrioventricular groove. The CS wall contains atrial myocardium. Thus, its size extensively depends on variability of blood flow and pressure. We present a variant PLSVC with unknown prevalence and a mild platypnea-orthodeoxia syndrome after recovery of COVID-19 related acute respiratory distress syndrome (ARDS).