BACKGROUND: Left atrial dissection (LatD) is a rare entity most commonly associated with mitral valve surgery. We have reviewed our experience with 4 patients to better define the etiology and the treatment of LatD. METHODS: From 1991 to 2012, 4 patients experienced LatD after surgery (1 of 6,302, or 0.02%, of isolated coronary artery bypass grafting patients and 3 of 1,895, or 0.16%, of mitral valve patients). Patient and perioperative data and management were reviewed. RESULTS: Two patients were women, and ages ranged from 49 to 80 years. Three patients underwent mitral procedures (two replacements with coronary artery bypass grafting and one repair) for mitral regurgitation. One patient underwent emergent isolated coronary artery bypass grafting after cardiopulmonary resuscitation for a left main dissection during percutaneous coronary intervention. Three LatDs were found during surgery, and one LatD was found 12 days after mitral repair and was successfully treated nonoperatively. The LatD was located along the posterior atrial wall originating from the atrioventricular junction in all cases and obstructed mitral valve inflow. Operative repair focused on the evacuation of hematoma, obliteration of the false lumen, and repair of the entry injury. No mortality occurred. CONCLUSIONS: Left atrial dissection is a rare complication of cardiac surgery, probably related to a contained atrioventricular separation allowing pressurized blood to separate the layers of the posterior left atrium. Prompt intraoperative diagnosis, obliterating the false cavity, and addressing the entry point are essential. In contrast, a nonoperative approach in a stable patient with a delayed LatD suggests healing of the dissection, and atrial remodeling occurs.
