Surgical redo mitral valve replacement in high-risk patients: The real-world experience

INTRODUCTION: Redo surgical mitral valve replacement (SMVR) remains the gold standard treatment in patients with a history of mitral valve surgery presenting with recurrent mitral valve pathologies. Whilst this procedure is demanding, it is an inevitable intervention for some indications, such as infective endocarditis, thrombosis, or multivalve procedures. In this study, we aim to evaluate our institutional experience with SMVR on a real-life cohort, identifying the factors that contribute to poor surgical outcomes whilst avoiding selection bias.

METHODS: Between March 2012 and November 2020, 58 consecutive high-risk patients underwent a redo SMVR at our institution. The primary endpoints of this study were 30-day and 1-year mortality. The secondary endpoint was the development of any postoperative adverse events. We analyzed and compared the survival in patients undergoing an isolated SMVR and in those that required at least one concomitant procedure.

RESULTS: The overall operative, 30-day, and 1-year mortality were 3.4%, 22.4%, and 25.9%, respectively. The mortality in patients undergoing isolated SMVR was significantly lower than in patients requiring concomitant procedures. The multivariable regression model showed that NYHA Class IV, infective endocarditis, and postoperative dialysis were significantly associated with 30-day mortality. Society of Thoracic Surgeons Score, infective endocarditis, concomitant procedures, and mechanical valve implantation appeared to predict long-term mortality.

CONCLUSION: This study illustrates that SMVR after prior mitral valve surgery presents a demanding procedure with high operative risk, significant mortality, and morbidity. Whilst this procedure is inevitable for some indications, a careful patient selection and risk stratification provides acceptable surgical results in this cohort.