Incidental left atrial blood cyst in a patient undergoing transcatheter aortic valve replacement.

Blood cysts of the heart are benign cardiovascular tumors found incidentally in approximately 50% of infants who undergo autopsy at less than 2 months of age. These congenital cysts, frequently present on the atrioventricular valves of infants, are exceedingly rare in adults. Nonetheless, in adults, cardiac blood cysts have been found on the mitral valve, papillary muscles, right atrium, right ventricle, left ventricle, and aortic, pulmonic, and tricuspid valves. Reported complications include left ventricular outflow obstruction, occlusion of the coronary arteries, valvular stenosis or regurgitation, and embolic stroke. In high-risk patients with severe aortic stenosis, transcatheter aortic valve replacement has emerged as an alternative to surgical replacement. Transesophageal echocardiography plays a fundamental role in evaluating the feasibility of intraprocedural transcatheter aortic valve replacement, in measuring aortic annular size, in guiding placement of the prosthetic device, and in looking for possible complications. The embolic risk of rapid pacing and transcatheter aortic valve replacement in a patient with an intracardiac blood cyst is unknown, and such a case has not, to our knowledge, been reported heretofore. We present the case of a 78-year-old woman with severe aortic stenosis, in whom a blood cyst was incidentally found in the left atrium upon transesophageal echocardiography. She underwent successful transcatheter aortic valve replacement without embolic complication.