Thromboembolic complications after surgical correction of mitral regurgitation - Incidence, predictors, and clinical implications

Objectives We sought to define thromboembolic risk after surgery for mitral regurgitation (MR), particularly ischemic stroke (IS) compared with the general population. Background Guidelines recommend surgery in asymptomatic patients with MR, but IS risks are unknown. Methods In 1,344 patients (age 65 +/- 12 years) consecutively operated for MR (procedures: 897 mitral valve repair [MRep] and 447 valve replacement: 231 mechanical mitral valve replacement [MVRm], 216 biological mitral valve replacement [MVRb]), thromboembolic complications, particularly IS (diagnosed by neurologists), during follow-up were assessed early (<30 days), midterm (30 to 180 days), and long-term (>= 180 days). Results Ischemic stroke occurred in 130 patients: 1.9 +/- 0.4% and 2.7 +/- 0.5% at 30 days and 180 days, respectively, and 8.1 +/- 0.8% at 5 years. We found that IS rates were lowest after MRep versus MVRb and MVRm (6.1 +/- 0.9% vs. 8 +/- 2.1%, and 16.1 +/- 2.7% at 5 years, respectively, p < 0.001). Comparison with population-expected IS showed high risk at <30 days (risk ratio 41, 95% confidence interval 26 to 60, p < 0.001 but p > 0.10 between procedures) and moderate risk at >30 days (risk ratio 1.7 overall; 1.3 for MRep; 0.98 for MVRb; 4.8 for MVRm). Beyond 180 days, IS risk declined further and was similar to the population for MRep (relative risk 1.2) and for MVRb (relative risk 0.9). Bleeding risk >30 days was lowest in MRep versus MVRb and MVRm (10-year risk 7 +/- 1%, 14 +/- 4%, and 16 +/- 3%, respectively). Conclusions Thromboembolic complications after MR surgery are a reason for both concern and encouragement. The risk of IS is notable early, irrespective of procedure, but in the long term it is not greater than in the population after MRep and MVRb. Preference for MRep should be emphasized, and trials aiming at preventing IS should be conducted to reduce thromboembolic and hemorrhagic risk after surgery for MR.