Atrio-Ventricular-Dissection (AVD) - A Devastating Complication after Mitral Valve Surgery

Objectives: AVD is a rare but mostly fatal complication after mitral valve (MV) surgery, associated with high mortality. The optimal treatment strategy is unknown.

Methods: Between 2000 and 2012, a total of 8868 patients underwent isolated or combined MV surgery at our institution. 15 (0.17%) patients were identified who developed left sided AVD. Data on preoperative variables, operative strategy, complications, and outcomes were collected and analyzed. Primary indication for surgery was mitral regurgitation (MR) in 9 (60%) patients and mitral stenosis in 6 (40%). Mean age of patients was 70.5 ± 15.0 year and 5 (33%) were male.

Results: MV pathology included MR in 8 patients, mitral stenosis in 6, and endocarditis in 1 patient. Severe mitral leaflet and/or mitral annular calcification was present in 10 (67%) patients. Prior to development of AVD, MV repair with implantation of an annuloplasty ring (mean size 33.0 ± 2.6 mm) was performed in 27% of patients (n = 4) and MV replacement (mean size of 29.0 ± 2.0 mm) was performed in 73% (n = 11). Concomitant procedures consisted of aortic valve replacement (n = 6), tricuspid valve repair (n = 2), atrial fibrillation ablation (n = 4), ASD closure (n = 1), and coronary bypass grafting (n = 2). AVD was identified intraoperatively in 87% of patients (n = 13) due to severe bleeding and/or hematoma. Delayed AVD was detected in 13% of patients (n = 2) with severe postoperative bleeding. Surgical strategy consisted of removal of the previously implanted prosthesis/repair followed by implantation of a pericardial patch from inside the heart in 11 (73%) patients, followed by re-implantation of the prosthesis. In the remaining 4 (27%) patients, bleeding was controlled with sutures placed on the external posterior left atrial/ventricular wall. Intraoperative mortality occurred in 3 (20%) patients. Postoperative complications consisted of low cardiac output syndrome (LCOS) with IABP support (n = 4) or ECMO (n = 1), and non cardiac complications. 30-day-mortality was 53% (n = 8), with causes of death being LCOS in 5 patients, multisystem organ failure in 2 patients, and myocardial wall rupture in 1 patient. One patient died 3 months postoperatively of LCOS. A total of 6 patients (40%) were discharged from hospital, 5 of which underwent pericardial patch repair. After a mean follow-up period of 4 years, 4 patients are alive.

Conclusions: Our data shows that surgical repair with patch reconstruction and epicardial tissue sealing improves survival.