QRS duration predicts sudden cardiac death in hypertensive patients undergoing intensive medical therapy: the LIFE study

Aims To determine whether QRS duration predicts sudden cardiac death (SCID) in patients with left ventricular hypertrophy and treated hypertension. Methods and results Over 4.8 +/- 0.9 years follow-up of 9193 hypertensive patients with electrocardiographic evidence of LVH who were treated with atenolol- or losartan-based regimens, 178 patients (1.9%) suffered SCD. In multivariable analysis including randomized treatment, changing blood pressure over time, and baseline differences between patients with and without SCID, QRS duration was independently predictive of SCID (HR per 10 ms increase = 1.22, P < 0.001). Baseline QRS duration remained a significant predictor of SCD even after controlling for the presence or absence of left bundle branch block (HR = 1.17, P 0.001) and for changes in ECG LVH severity over the course of the study (HR = 1.16, P = 0.017). Conclusion In the setting of aggressive antihypertensive therapy, prolonged QRS duration identifies hypertensive patients at higher risk for SCID, even after controlling for left bundle branch block, other known risk factors for SCD, and changes in blood pressure and severity of left ventricular hypertrophy.