Conservative Management of Left Atrial Dissection and Associated Complete Heart Block Following Cardiac Surgery.

Background: Left atrial (LA) dissection is a rare, but potentially serious, complication that most commonly arises following mitral valve surgery.

Case Summary: In this report, the authors describe an unusual case of a patient presenting with chest pain and presyncopal symptoms after cardiac surgery who ultimately received a diagnosis of LA dissection and associated complete heart block. Although permanent pacemaker placement was required as a result of recurrent episodes of complete heart block, the patient was otherwise managed safely using a conservative approach without surgical reintervention.

Discussion: LA dissection is a surgical complication most commonly identified following mitral valve intervention, and it may be associated with debridement of calcium along the mitral annulus. Urgent surgical repair is indicated when LA dissection results in hemodynamic instability, typically through obstruction of the left atrial outflow, obstruction of the left atrial inflow, or cardiac tamponade. Although complete heart block is not a previously reported downstream complication of LA dissection, aspects of the atrioventricular (AV) node, particularly the compact AV node, lie within the interatrial septum and could be damaged by dissection.

Take-home Messages: LA dissection is a rare, but potentially serious, complication that most commonly arises following mitral valve surgery. Although the presence of hemodynamic instability renders LA dissection a surgical emergency, a conservative approach that avoids reintervention may otherwise be considered.