Propensity Matched Comparison of Two Different Access Modes for Minimally Invasive Mitral Valve Surgery

Mitral valve surgery is being performed routinely using minimally invasive operative techniques. We aimed comparing perioperative and long-term outcomes of minimally invasive mitral valve surgery using two different surgical approaches, partial upper sternotomy (PUS) versus right anterolateral minithoracotomy (RAT). From January 1998 through December 2015 1006 patients underwent mitral valve surgery using a minimally invasive access in our institution. Logistic regression analysis was used to identify covariates among 18 patient variables including the type of mitral valve surgery. Using the significant regression coefficients, each patient's propensity score was calculated, allowing selectively matched subgroups of 243 patients each. Results are based on the matched cohorts between the two groups. The PUS approach was performed by eight surgeons whereas the RAT approach by two. PUS led to slightly longer duration of the cross-clamp time (100±28 vs. 88±26minutes, p