CHA2DS2-VASc Score: A Predictor of Thromboembolic Events and Mortality in Patients With an Implantable Monitoring Device Without Atrial Fibrillation

Abstract

Objective: To determine if the CHA₂DS₂-VASc score (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65-74 years, sex category) predicts thromboembolism and death in patients without atrial fibrillation in a population with implantable cardiac monitoring devices.

Patients and methods: A retrospective review utilizing the Rochester Epidemiology Project research infrastructure was conducted to evaluate the CHA₂DS₂-VASc tool as a predictor of mortality and ischemic stroke, transient ischemic attack, or systemic embolism in patients without atrial fibrillation. An implantable device was required in the inclusion criteria to discern the absence of atrial fibrillation. The study period was January 1, 2004, through March 7, 2016.

Results: The study population (N=1606) had a mean (SD) age of 69.8 (12.6) years and median follow-up of 4.8 years (range, 0-12 years; quartile 1, 2.6 years and quartile 3, 8.1 years). The number of thromboembolic and mortality events stratified by CHA₂DS₂-VASc score groupings of 0 to 2 (399 patients), 3 to 5 (756 patients), and 6 to 9 (451 patients) were 12 (3.0%), 109 (14.4%), and 123 (27.3%) and 22 (5.5%), 205 (27.1%), and 214 (47.4%), respectively. The CHA₂DS₂-VASc score predicted thromboembolism and death. The hazard ratios (HRs) for thromboembolic events for CHA₂DS₂-VASc scores 3 to 5 and 6 to 9 were 4.84 (95% CI, 2.66-8.80) and 10.53 (95% CI, 5.77-19.21) (reference group, scores 0-2). The HRs for death for the corresponding score categories were 4.45 (95% CI, 2.86-6.91) and 8.18 (95% CI, 5.23-12.78). The CHA₂DS₂-VASc score also predicted development of atrial fibrillation, for which the HRs for scores 3 to 5 and 6 to 9 were 1.51 (95% CI, 1.13-2.00) and 2.17 (95% CI, 1.60-2.95).

Conclusion: The CHA₂DS₂-VASc tool predicts thromboembolic events and overall mortality in patients without atrial fibrillation who have implantable devices.