Ann Thorac Surg 2008;85:1459. doi:10.1016/j.athoracsur.2007.05.066
© 2008 The Society of Thoracic Surgeons
Images in Cardiothoracic Surgery
Unusual Appearance of Clot in the Left Atrium
Betty S. Kim, MD*,
Paul A. Pirundini, MD,
Kevin J. Lilly, CCP,
Robert J. Rizzo, MD
Department of Cardiac Surgery, Brigham and Women’s Hospital, Boston, and Division of Cardiac Surgery, Cape Cod Hospital, Hyannis, Massachusetts
* Address correspondence to Dr Kim, Brigham and Women’s Hospital, Department of Cardiac Surgery, 75 Francis St, Boston, MA 02115-6110 (Email: bkim5{at}partners.org).
A 73-year-old man had experienced episodes of palpitations for more than 1 year. The palpitations occurred when the patient was in a supine position and they were not related to exertion. They were not associated with syncope or chest pain. The cardiac workup included a Holter monitor that showed a predominantly sinus rhythm with premature atrial contractions and several episodes of nonsustained atrial tachycardia. A transthoracic echocardiogram demonstrated a left atrial mass. A transesophageal echocardiogram confirmed the presence of an echodensity attached to the posterior aspect of the left atrium that measured 1.4 x 1.5 cm with calcium in the mass (Fig 1). There was no evidence of thrombus in the left atrium or its appendage, no mitral valve regurgitation, and no interatrial septal communication. Preoperatively the patient underwent a cardiac catheterization that showed significant left anterior descending and circumflex coronary artery disease.
At surgery the patient was placed on cardiopulmonary bypass with bi-caval cannulation. The left atrium was entered through Sondergaard’s groove and was inspected. The mass was unusual appearing, white, with a convoluted surface. It was found to be sessile and adherent to the posterior wall of the left atrium several centimeters away from the posterior mitral annulus (Fig 2). It did not have the typical appearance of a myxoma, nor was it in the classical location of a myxoma, which usually originates off the atrial septum. The base of the mass was resected off the muscle and the endocardium was reapproximated (Figs 3 and 4).
After closure of the left atrium, the coronary artery bypasses were performed to the left anterior descending and obtuse marginal branch of the circumflex artery. The patient’s recovery was uneventful except for postoperative junctional rhythm, which was resolved.
After extensive decalcification, histology confirmed focally calcified hyalinized fibrous tissue consistent with an organized mural thrombus with no evidence of myxoma or other malignancy. Anticoagulation was considered, but with reinstitution of beta blockers the patient had no further documentation or clinical symptoms of tachycardia. At 2 months follow-up, he remained in normal sinus rhythm.
