Relationship between degree of left ventricular dysfunction, symptom status, and risk of embolic events in patients with atrial fibrillation and heart failure.

BACKGROUND AND PURPOSE: Limited data exists regarding the relationship between left ventricular systolic dysfunction (LVSD) and heart failure (HF) symptoms and embolic risk among patients with atrial fibrillation.

METHODS

Participants in the Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events (ACTIVE) trials with HF, but not randomized to oral anticoagulation, were categorized as having preserved versus reduced ejection fraction. If reduced, LVSD was classified as mild, moderate, or severe. Symptoms were quantified using New York Heart Association class.The primary outcome was a composite of stroke, transient ischemic attack, and systemic embolism.

RESULTS

There were 3487 antiplatelet-treated patients with HF at baseline. Of these patients, 969 (46.8%) had HF with preserved ejection fraction and 1103 (53.2%) had HF with reduced ejection fraction. During 3.6 years of mean follow-up, first occurrence of stroke, transient ischemic attack, or systemic embolism occurred in 386 patients.The strongest independent predictors of embolic events were age ≥75 years (hazard ratio 2.55; confidence interval, 1.85-3.53), prior stroke or transient ischemic attack (hazard ratio 2.07; 95% confidence interval, 1.65-2.60), and female sex (hazard ratio 1.37; confidence interval, 1.11-1.69). However, ejection fraction <0.50, degree of LVSD, and New York Heart Association class did not predict embolic events. Patients with HF with preserved ejection fraction exhibited similar risk of embolic events as those with HR with reduced ejection fraction: 4.3% versus 4.4% per 100 person-years (hazard ration 1.01; 95% confidence interval, 0.78-1.31). Risk of embolic events was similar across categories of LVSD (P for trend =0.96) and New York Heart Association class (P for trend =0.57).

CONCLUSION

Among HF patients in ACTIVE, neither the presence of LVSD or degree of symptom severity influenced risk of embolic events.