Predictors of Stroke after Minimally Invasive Mitral Valve Surgery Without the Cross-Clamp.

Minimally invasive mitral valve surgery (mini-MVS) with hypothermic fibrillatory arrest has been associated with an increased risk of stroke. We aim to investigate the incidence, predictors, and outcomes of stroke in a large cohort of patient who underwent clampless mini-MVS. Between January 2008 and June 2017, we performed 1,247 mini-MVSs. The clinical, operative, and postoperative outcomes were analyzed. Univariable and multivariable regression analyses were used to identify predictors of postoperative stroke. The median follow-up was 5.2 years (IQR 2.6-7.5). The etiology of mitral valve (MV) disease was degenerative (60.4%, n=753), functional (12.8%, n=160), rheumatic (8.7%, n=109), endocarditis (3.1%, n=39), and re-operative MV surgery (14.9%, n=186). The overall incidence of postoperative neurologic event was 2.5% (n=31/1247). Univariable predictors of stroke were a higher STS mortality risk (6.0±11.8% vs. 3.3±5.2%, p<0.001), advanced age, (69.6±12.1 years vs. 63.0±13.6 years, p=0.002), female gender (71.0% vs. 46.3%, p=0.007), and a history of a cerebrovascular accident (CVA) (22.6% vs. 8.7%, p=0.008). Stroke patients had a higher 30-day mortality (22.6% vs. 1.6%, p<0.001) and a higher risk for long-term mortality (HR=5.56, 95% CI 3.2-9.6, p<0.001). Advanced age (OR 2.1; 95% CI, 1.1-4.0; p=0.02), female gender (OR 2.3; 95% CI, 0.9-5.2; p=0.05), and history of CVA (OR 3.1; 95% CI, 0.98-10.1; p=0.05) remained as independent predictors of stroke in the multivariable analysis. Our decade long experience indicates that clampless mini-MVS is associated with a low incidence of postoperative stroke, and that the predictors of stroke are not specific to this approach.