Case Study: Exploring a Variation of Partial Anomalous Pulmonary Venous Return of the Right Upper Pulmonary Vein into the Cephalic Portion of the SVC Causing a Left‐to‐Right Shunt in a 56‐year‐old Asian Female

Abstract

HypothesisPartial Anomalous Pulmonary Venous Return is the result of aberrant congenital cardiopulmonary development, and can go undiagnosed with late emergent presentation in older adulthood.SummaryPartial Anomalous Pulmonary Venous Return (PAPVR) is a highly variable disease that is often asymptomatic in children and may not present until later in adulthood either symptomatically, or as an incidental finding on radiology or autopsy. When considering the configuration of anatomic congenital anomalies, such as PAPVR in both children and adults, it is important to explore the embryological development. Due to the direct correlation between the cardiology and pulmonology in this case, the embryology of both systems must be understood and discussed to fully recognize the issue at hand and is further explored in detail later. The most common presentation of PAPVR involves the right upper pulmonary vein as it drains into the junction of the Superior Vena Cava (SVC) and right atrium creating a left‐to‐right shunt, and there is almost always an associated Atrial Septal Defect (ASD) present in PAPVR[1]. In the case presented, a 56‐year‐old Asian female was found to have PAPVR of the Right Upper Pulmonary Vein that drained into the cephalic portion of the SVC. A left‐to‐right shunt results in freshly oxygenated blood from the lungs being returned to, and mixed with, deoxygenated systemic blood in the right atrium. While having a right upper pulmonary vein drain into the SVC is the most common PAPVR, this case is rare as it is not associated with an ASD as previously described[2]. The abnormal site of attachment of the right pulmonary vein was noteworthy, because in most cases this vein will attach at the junction of the SVC and right atrium. In this case, the vein was draining into the cephalic portion of the SVC alone. This patient required a modified Warden’s procedure for successful surgical correction. While most cases are asymptomatic and the result of an incidental finding, the patient presented to the emergency department with a life‐threatening right atrial pressure of 80mmHG, which is clinically significant for Pulmonary Arterial Hypertension (PAH) and caused the patient to go into Right‐Sided Heart Failure. The patient also presented with significant right ventricular hypertrophy, as the result of consistent PAH.ConclusionPAPVR is a rare congenital cardiopulmonary defect that can remain undiagnosed and present later in adulthood. The diagnosis and treatment of this disease is particularly difficult due to its ability to remain undetected in childhood, slowly progress to insidious pathology, and present later in adulthood with potentially life‐threatening complications requiring surgical intervention. The variability of PAPVR must be explored further in order to improve the effective diagnosis and treatment of this rare congenital disease.Resources[1] Lyen, S. et al.2017. Anomalous pulmonary venous drainage: a pictorial essay with a CT focus. J Congenit Heart Dis[2] Ishida, N et al.2018. Surgical repair of partial anomalous pulmonary venous return with intact atrial septum in a 65‐year‐old woman: a case report. Journal of medical case reports