RESUMO
Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital heart disease in which one or more pulmonary veins drain into the systemic venous circulation. The abnormal connection between the pulmonary vein and the right atrium can result in a right-sided volume overload due to a left-to-right shunt, followed by eventual right-sided pressure overload and right ventricular failure. PAPVC is usually associated with an atrial septal defect but can present as an isolated finding. We present a case of isolated PAPVC resulting in right heart failure and predominantly pre-capillary pulmonary hypertension. We discuss the challenges in the diagnosis and medical management of isolated PAPVC and highlight the clinical and hemodynamic indications for pulmonary vasodilators and diuretics.