Magnetic Resonance Imaging of Complex Partial Anomalous Pulmonary Venous Return in Adults

Abstract

Adults with congenital cardiac abnormalities surpass the number of children because of better assessment of cardiac anatomy and function, monitoring, operative options, patient outcomes, and increased survival into adulthood.1 Partial anomalous pulmonary venous return may present in adulthood, particularly if asymptomatic with small shunt fraction. One or more pulmonary veins, most commonly an anomalous right upper pulmonary vein, connect to a systemic vein or the right atrium; this accounts for 0.5% of congenital cardiac defects. Cardiovascular imaging continues to evolve rapidly for accurate preoperative evaluation and operative planning. Although transthoracic echocardiography is the first-line tool for diagnosis, suboptimal acoustic windows may preclude adequate inspection of pulmonary veins or atrial septal defect to assess for appropriate baffling. Disadvantages of computed tomography include an inability to calculate shunt fraction, ionizing radiation, and a greater risk of nephrotoxicity than with gadolinium with cardiac magnetic resonance imaging (MRI).2 Anatomically, MRI provides noninvasive volumetric anatomic data and enables evaluation of systemic veins, as well as the number, origin, course, and drainage of all pulmonary veins, including anomalous connections or obstruction. Detection rate for each pulmonary vein is 57% for the right superior pulmonary vein, 62% in the left superior pulmonary vein, 76% in the right inferior pulmonary vein, and 86% in the left inferior pulmonary vein. MRI …