Progressive Dyspnea and Exercise Intolerance in an Adult With a Persistent Childhood Murmur

A 59-YEAR-OLD, 170-cm, 81-kg, previously healthy man with a past medical history of well-controlled essential hypertension (treated with carvedilol, quinapril, and furosemide) and a heart murmur that was originally detected in childhood presented to the authors’ institution for evaluation of worsening dyspnea and exercise intolerance of approximately 6 months’ duration. The patient denied anginal complaints. He was employed as a truck driver and had been able to perform his duties well until his symptoms began. The physical examination revealed the presence of a grade 3 to 4/6 holosystolic murmur heard best along both upper sternal borders that radiated to the neck (left > right). Cyanosis was appreciated in the patient’s fingertips. Mild clubbing of his fingers and toes were also noted. Resting arterial oxygen saturation determined by using pulse oximetry was 88% with the patient breathing room air. A laboratory analysis revealed a hemoglobin concentration of 20.0 g/dL but was otherwise unremarkable. Transesophageal echocardiography was performed and revealed the following images (Fig 1, Fig 2). What is the diagnosis? Is myocardial ischemia, valvular disease, or an uncorrected congenital abnormality responsible?