Interatrial Septum Dissection and Closure from Transseptal Puncture during Mitral Transcatheter Edge-to-Edge Repair: A Case Report

Abstract Background An 85-year-old woman was referred for mitral valve transcatheter edge-to-edge repair (TEER) following multiple heart failure hospitalizations related to her severe functional mitral regurgitation. In addition to previous transcatheter aortic valve replacement for aortic stenosis, her past medical history was significant for chronic steroid use related to microscopic polyangiitis leading to renal transplantation. Case summary Her procedure was complicated by an interatrial septum dissection with associated haemopericardium originating from the transseptal puncture site. To our knowledge, our case demonstrates the first use of an Amplatzer occluder device to manage this complication by preventing ongoing flow into the pericardial space. This complication occurred in the setting of a single, successful transseptal puncture in the typical location for a mitral valve TEER procedure, raising the consideration that chronic steroid use may be an underappreciated risk factor for iatrogenic interatrial septal damage. Discussion Transoesophageal echocardiography is integral to identifying and risk stratifying this complication, and imagers should have a low threshold to screen for it, particularly in the setting of haemodynamic compromise. The decision to deploy a closure device should be made on a case-by-case basis considering the risks and benefits of doing so compared with conservative management.