A Complicated Case of Dyspnea
A 60-year-old male with a history of essential hypertension and a ten year history of paroxysmal atrial fibrillation (AF) presents with several weeks of progressive dyspnea on exertion and orthopnea. The physical exam was remarkable for an elevated jugular venous pulsation and an irregular rhythm. Electrocardiography and chest x-ray were performed (see Figures 1 and 2). Echocardiography showed a left ventricular ejection fraction of 62% (normal > 60%), with moderate right ventricular enlargement and moderately decreased systolic function. Tricuspid regurgitation velocity was 3.6 meters/second consistent with a calculated pulmonary artery systolic pressure of 81 mmHg (using an estimated right atrial pressure of 15 mmHg).
Two years ago he underwent a pulmonary vein isolation ablation for the treatment of AF and at that time echocardiography showed a moderately enlarged left atrium but no other abnormalities. Treatment was initiated with intravenous diuresis and his symptoms improved. Pulmonary CT angiogram was normal without evidence of pulmonary embolism or pulmonary vein stenosis. Coronary angiography showed no obstructive coronary artery disease. A right-heart catheterization was performed which showed a mean pulmonary artery pressure of 34 mmHg and a pulmonary vascular resistance of 3.3 Wood units.
Three weeks later he returned to clinic with continued symptoms of dyspnea. He remained in atrial fibrillation. Overnight oximetry was performed at his home and suggested severe obstructive sleep apnea (OSA), with 26% of measurements below 90% oxygen saturation. A polysomnogram was performed revealing severe OSA with an apnea-hypopnea index of 26.1/hour.
What is the next most appropriate step in the management of this patient?