Risk of neurologic events after surgery for mitral valve insufficiency and concomitant Cox-maze IV procedure for atrial fibrillation. A nationwide register-based study.

Objectives: Analysis of the long-term risks of ischaemic stroke and cerebral bleeding in patients with atrial fibrillation after mitral valve surgery and concomitant Cox-maze IV procedure.

Methods: In total, 397 patients with symptomatic degenerative mitral valve insuffciency and atrial fibrillation, underwent mitral valve surgery and Cox-maze IV in Sweden between 2009 and 2017. In this retrospective nationwide analysis, patients were followed in national patient registers until 30 September 2022.

Results: There were 4 deaths within 30 days (1.0%). Mean follow-up was 8.7 (0.1-13.4) years. Survival without ischaemic stroke or cerebral haemorrhage at 5 and 10 years were 90% and 74%, respectively. Nineteen patients experienced an ischaemic stroke, of which 4 were fatal. Five of 34 patients (14.7%) with a history of stroke preoperatively experienced ischaemic stroke during follow-up. The linearized rate of ischaemic stroke per patient-year was 0.6% and was similar regardless of left atrial appendage closure during surgery or whether a mechanical valve was inserted. The observed ischaemic stroke rate was lower than the predicted rate for all CHA2DS2-VASc score groups. Fourteen patients suffered cerebral bleeding, of which 3 were fatal. Patients who experienced cerebral bleeding were older and had higher mechanical valve implantation rate than those without cerebral bleeding.

Conclusions: Surgery for mitral valve insufficiency and concomitant Cox-maze IV can be performed with low perioperative risk. There is a low continuing risk of stroke long-term postoperatively that correlates with a higher CHA2DS2-VASc score. Patients with preoperative stroke are at increased risk of postoperative stroke despite atrial fibrillation surgery.