Long-term Clinical Outcomes in Contemporary Patients Undergoing Left Atrial Appendage Occlusion Procedures in Ontario, Canada

Background: Percutaneous left atrial appendage occlusion (LAAO) is an alternative for stroke prevention in patients with atrial fibrillation with contraindications to oral anticoagulation. Population-level real-world data describing the use and outcomes of LAAO procedures are evolving, with a paucity of longer-term follow-up data. We report on the patient characteristics, procedure complications, and longer-term clinical outcomes in all patients undergoing LAAO procedures in Ontario, Canada. Methods: All patients undergoing LAAO procedure between April 1, 2013 and March 31, 2022 were identified. Linked administrative databases were utilized to determine patient clinical and procedural characteristics. Outcomes of interest included procedural complications at 7 and 30 days, and longer-term rates of stroke, bleeding, all cause rehospitalization, and mortality. Results: A total of 549 individuals were included in the study cohort. The average age was 75 +/- 8 years, with 66% being of male sex, with a mean CHA2DS2VASc score of 4.4 +/- 1.6, and with 68% not receiving oral anticoagulation. Follow-up for 2.6 +/- 2.0 patient-years was available. Stroke occurred in 2.8% during the follow-up period (1.1 per 100 patient-years), bleeding in 10% (4.0 per 100 patient-years), and any hospital readmission in 63% (43 per 100 patient-years). A total of 29% of the cohort died during the follow-up period (11 per 100 patient years), with 1.8% of the cohort dying during the procedural hospitalization. The mortality rate was unchanged during the study period (P for trend = 0.72). Conclusions: Long-term stroke and bleeding rates are low in patients undergoing LAAO procedures in Ontario, Canada. All-cause mortality in this population is high and remained unchanged during the study period.