ECG Features Associated With Adverse Cardiovascular Outcomes in Patients With Atrial Fibrillation: A Combined AFFIRM and AF‐CHF Analysis

ECG and Cardiovascular Outcomes in AF Background The association between standard parameters from a simple 12‐lead ECG (i.e., QRS duration and PR, JT, and QT intervals) and adverse cardiovascular outcomes (cardiovascular mortality, all‐cause mortality, arrhythmic mortality, and hospitalizations) in patients with a history of atrial fibrillation (AF) has not been previously studied. Methods and Results A pooled analysis of patient‐level data was conducted on 5,436 patients, age 68.2 ± 8.3 years, 34.8% female, with a history of non‐permanent AF randomized in AFFIRM and AF‐CHF trials. The predictive value of ECG parameters was assessed in AF and sinus rhythm in multivariate Cox regression models. During a follow‐up of 40.8 ± 16.3 months, QRS duration >120 milliseconds was independently associated with all‐cause mortality (hazard ratio [HR] 1.46, 95% confidence interval [CI; 1.21–1.76] in AF, P < 0.001), cardiovascular mortality (HR 1.75, 95% CI (1.15–2.65) in sinus rhythm, P = 0.009; HR 1.56, 95% CI [1.27–1.93] in AF, P < 0.001), arrhythmic mortality (HR 1.90, 95% CI [1.09–3.32] in sinus, P = 0.024; HR 1.84, 95% CI [1.35–2.51] in AF, P < 0.001), any hospitalization (HR 1.15, 95% CI [1.02–1.29] in AF, P = 0.027), and cardiovascular hospitalization (HR 1.21, 95% CI [1.06–1.37] in AF; P = 0.004). Increased PR interval (>200 milliseconds) was independently associated with cardiovascular (HR 1.56, 95% CI [1.11–2.21], P = 0.010) and arrhythmic (HR 1.91, 95% CI [1.14–3.18], P = 0.004) mortality. The JT and QTc intervals were not predictive of mortality. Conclusions Simple parameters from standard ECGs are significantly and independently associated with adverse cardiovascular outcomes in patients with a history of AF.