Long-Term Outcomes of Right Minithoracotomy Versus Hemisternotomy for Mitral Valve Repair

Objective Minimally invasive mitral valve repair has been increasingly adopted. Right minithoracotomy (RT) and lower hemisternotomy (HS) have each been associated with improved short-term outcomes; however, these approaches have not been directly compared to each other. The aim of this study was to compare long-term survival and durability of 2 minimally invasive approaches to mitral repair. Methods We retrospectively identified all isolated mitral repairs performed via RT or HS between October 1997 and June 2018; 100 RT cases and 719 HS cases were included. Outcomes of interest were postoperative complications, long-term survival, and freedom from mitral reoperation. A Cox proportional hazard model was used to compare RT and HS to a reference cohort of full-sternotomy cases. Total observation time was 9,901 patient-years and mean follow-up time was 12.2 years. Results Mean age was 58±12 years in the RT group and 56±13 years in the HS group ( P = 0.2). The RT group had longer bypass (143 minutes vs. 112 minutes; P < 0.001) and cross-clamp times (99 minutes vs. 78 minutes; P < 0.001) compared with the HS group. There were no differences in operative mortality or 30-day outcomes. Survival at 5, 10, and 15 years was 99% (96-100), 92% (85-100), and 69% (30-100) in the RT group and 98% (97-99), 92% (90-94), and 89% (86-92) for HS ( P < 0.9). There were no differences in risk-adjusted survival between RT, HS and full sternotomy. No long-term mitral reoperations occurred in the RT group and 8 (1%) occurred in the HS group ( P < 0.50). Conclusions Minimally invasive mitral valve repair can be performed safely through RT or HS with excellent survival and durability at 15 years.