First-degree atrioventricular block is associated with heart failure and death in persons with stable coronary artery disease: Data from the Heart and Soul Study

Abstract

Aims First-degree atrioventricular block (AVB) has traditionally been considered a benign electrocardiographic finding in healthy individuals. However, the clinical significance of first-degree AVB has not been evaluated in patients with stable coronary heart disease. We investigated whether first-degree AVB is associated with heart failure (HF) and mortality in a prospective cohort study of outpatients with stable coronary artery disease (CAD). Methods and resultsWe measured the PR interval in 938 patients with stable CAD and classified them into those with (PR interval <220 ms) and without (PR interval <220 ms) first-degree AVB. Hazard ratios (HRs) and 95 confidence intervals were calculated for HF hospitalization and all-cause mortality. During 5 years of follow-up, there were 123 hospitalizations for HF and 285 deaths. Compared with patients who had normal atrioventricular conduction, those with first-degree AVB were at increased risk for HF hospitalization (age-adjusted HR 2.33: 95 CI 1.493.65; P 0.0002), mortality [age-adjusted HR 1.58; 95 CI (1.132.20); P 0.008], cardiovascular (CV) mortality [age-adjusted HR 2.33; 95 CI (1.284.22); P 0.005], and the combined endpoint of HF hospitalization or CV mortality (age-adjusted HR 2.43: 95 CI 1.643.61; P ≤ 0.0001). These associations persisted after multivariable adjustment for heart rate, medication use, ischaemic burden, and QRS duration. Adjustment for left ventricular systolic and diastolic function partially attenuated the effect, but first-degree AVB remained associated with the combined endpoint of HF or CV death (HR 1.61, CI 1.022.54; P 0.04). Conclusion In a large cohort of patients with stable coronary artery disease, first-degree AVB is associated with HF and death. © 2011 The Author.