Left Atrial Compression Caused by an Intrapericardial Hematoma after Coronary Artery Bypass Graft Surgery

BackgroundLeft atrial compression (LAC) is an uncommon condition that causes left ventricular inflow obstruction. The clinical and pathologic features are similar to those of mitral stenosis. Impaired left ventricular filling may cause hypotension, syncope, or shock. The increased left atrial pressure causes retrograde increase of the pressure throughout the pulmonary circulation with subsequent signs of congestion.Case ReportAn 84-year-old man presented with LAC caused by a focal tamponade related to a pericardial hematoma as a complication of coronary artery bypass graft (CABG) surgery. The formation of the hematoma occurred 3 weeks postsurgery. The echocardiographic study before discharge at day 12 after CABG surgery showed neither a focal hematoma nor a tamponade. The diagnosis was made 6 days later.Why Should an Emergency Physician Be Aware of This?Intrapericardial tamponade caused by bleeding is a known complication of CABG surgery in the early postoperative stage. However, emergency physicians should be aware that a postoperative hematoma may also present as a focal tamponade because of postoperative adhesion by scar formation. The literature of LAC is limited. The most reported causes of LAC are compression caused by structures of the gastrointestinal tract, followed by thoracic aortic pathology. A Medline search for the terms “left atrial compression and hematoma” and “left atrial compression and intrapericardial hematoma” found only 31 and 4 hits, respectively. We also briefly discuss the import role of bedside echocardiography in the diagnostic process of LAC in the emergency medicine department.