Spontaneous left atrial hematoma mimicking an acute aortic syndrome: the utility of high-resolution computed tomography.

A 69-year-old man with no history of chest trauma was admitted to our institution complaining of blunt and severe central chest pain of cataclysmic onset radiating to the back. His medical history was remarkable only for a chronic atrial fibrillation treated with warfarin and amiodarone. On arrival, his ECG showed atrial fibrillation at 120 bpm with no signs of myocardial ischemia. Laboratory examination was uneventful except for an international normalized ratio of 7. With the presumptive diagnosis of acute aortic syndrome, a thoracoabdominal high-resolution contrast-enhanced computed tomography scan was performed that showed a large mass at the level of the left atrium (LA) and a moderate pericardial effusion (Figure 1 and Movie I in the online-only Data Supplement). Linear attenuation coefficients of the LA mass and pericardial fluid were suggestive of acute clot and blood (60 and 50 Hounsfield units, respectively). No signs of malignancy, pulmonary embolism, or aortic disease were found. During evaluation, our patient’s clinical condition deteriorated rapidly with signs and symptoms of cardiogenic shock; thus, emergent intubation and inotropic support were established. Preoperative and intraoperative transesophageal echocardiogram demonstrated a 2 3-cm LA tumor bulging into the lumen and involving the left pulmonary veins and the mitral valve but with no apparent compromise (Figure 2 and 3 and Movie II in the online-only Data Supplement). With the diagnosis of LA hematoma, anticoagulation was reversed with prothrombin complex (Prothromplex), and emergent surgery was undertaken. Through a median sternotomy, the pericardium was opened and abundant hemopericardium was drained with immediate hemodynamic improvement. On the beating heart, we observed a large hematoma located at the level of the posterolateral wall of the LA and extending to the left pulmonary veins. No pericardial adhesions or signs of infiltration were present. Despite careful examination, no distinct point of bleeding was demonstrated. The left atrioventricular groove seemed intact. To exclude stenosis of the left pulmonary vein or mitral valve dysfunction, we decided to go on pump and cross-clamp the aorta. The pulmonary veins and mitral valve were inspected through a left atriotomy. A bulky mass was apparent under the endocardium of the LA occupying a large area of the LA lumen. However, a 10-mm Hegar dilator passed easily through the left pulmonary veins. In addition, the inflow area of the mitral valve seemed unobstructed, the annulus looked intact, and the leaflets did not prolapse; therefore, we decided not to open the endocardium and drain the hematoma. Our patient had an uneventful recovery and was discharged home on postoperative day 7. Three months after surgery, a follow-up echocardiogram depicted resolution of the LA hematoma (Movie II in the online-only Data Supplement).