Rare case of undiagnosed supracardiac total anomalous pulmonary venous return in an adult.

A 50-year-old man presented to his cardiologist with a 1-year history of palpitations and exertional chest pressure , dyspnea, and dizziness. His surgical and medical history was unremarkable, including no history of tobacco use, hyper-tension, or hyperlipidemia. Coronary angiography, transtho-racic and transesophageal echocardiography, and cardiac magnetic resonance imaging led to a diagnosis of an anomalous left upper pulmonary vein draining to the innominate vein and a secundum atrial septal defect (ASD). Palpitations correlated with isolated ventricular and supraventricular beats on Holter monitoring. He was referred to our institution for management. Physical examination revealed a dark-complexioned man with a body mass index of 25.6 kg/m 2 , a blood pressure of 117/70 mm Hg in the right arm, a heart rate of 86 bpm, and an oxygen saturation of 93% on room air. His jugular venous pulsations were normal. His lungs were clear to ausculta-tion. Cardiac examination revealed a right ventricular heave, a normal S1, and a persistently split S2. P2 was not loud, and no murmurs were appreciated. There was no hepatomegaly, peripheral clubbing, or edema. His ECG showed normal sinus rhythm at a rate of 89 bpm. His QRS axis was 120°, and there was a right bundle branch with a QRS duration of 120 milliseconds. The outside echocardiograms showed an interatrial communication with bidirectional shunting, a severely dilated right ventricle with mildly decreased systolic function, mild right ventricular hypertension, and a markedly dilated innom-inate vein. Because transesophageal echocardiography was prematurely terminated as a result of patient intolerance, the pulmonary veins were not visualized. The outside cardiac magnetic resonance imaging showed a large secundum ASD and severe right atrial and right ven-tricular dilation. However, on review of the study, imaging of the pulmonary veins was determined to be nondiagnostic but suspicious for supracardiac total anomalous pulmonary venous connection (TAPVC). Therefore, cardiac magnetic resonance imaging was repeated to better delineate the pulmonary venous anatomy before further invasive testing. Repeat cardiac magnetic resonance imaging showed all 4 pulmonary veins joining a confluence behind the left atrium without evidence of pulmonary vein obstruction (Figure 1A). A large vertical vein arising from the confluence drained to the left innominate vein, resulting in a markedly dilated left innominate vein, superior vena cava, and right atrium (Figure 1B). The right ventricle was severely dilated (right ven-tricular end-diastolic volume, 216 mL/m 2 [normal, 86.2±14.1 mL/m 2 ]) with normal systolic function (ejection fraction, 52% [normal, 55.1±3.7%]). …