Abstract 9245: Incident Atrial Fibrillation is Associated with an Increased Risk of Sudden Cardiac Death in Hypertensive Patients During Antihypertensive Therapy: The LIFE Study

Abstract

Background: Incident atrial fibrillation (AF) is associated with an increased risk of mortality in the general population and after myocardial infarction. Prevalent AF is associated with an increased risk of appropriate device therapies for ventricular arrhythmias in patients with ICDs and with a higher rate of sudden cardiac death (SCD) in advanced heart failure patients. However, whether hypertensive patients with incident AF are at higher risk of SCD has not been examined. Methods and Results: The predictive value of incident AF for SCD was examined in 8831 hypertensive patients with ECG left ventricular hypertrophy (LVH) with no history of AF, in sinus rhythm on their baseline ECG, who were randomly assigned to losartan- or atenolol-based treatment. During 4.8±0.9 years mean follow-up, new-onset AF occurred in 701 patients (7.9%) and SCD in 151 (1.7%). SCD was significantly more frequent in patients with new AF than in those without (3.6 vs 1.5%, p<0.001). In univariate Cox analyses, new-onset AF, treated as a time-varying covariate, was associated with a subsequent 113% higher risk of SCD (HR 2.13, 95% CI 1.31-3.44, p=0.002). In multivariate Cox analyses adjusting for randomized treatment, age, sex, race, body mass index, diabetes, history of heart failure, myocardial infarction, ischemic heart disease, stroke, peripheral vascular disease, smoking, serum total and HDL cholesterol, creatinine, glucose, urine albumin/creatinine ratio and for incident MI, in-treatment heart rate, diastolic and systolic pressure, Cornell voltage-duration product and Sokolow-Lyon voltage LVH treated as time-varying covariates, incident AF remained associated with a 74% increased risk of SCD (HR 1.74, 95% CI 1.05-2.91, p=0.033). Conclusions: The development of new-onset of AF identifies hypertensive patients at increased risk of SCD, independent of the higher prevalence of risk factors in patients with new AF, treatment effects, in-treatment blood pressure and the established predictive value of in-treatment ECG LVH and heart rate for SCD in this population.