Baseline QRS duration ≥120 ms was associated with an increased risk of death (HR 1.35; 95% CI 1.07-1.70; P=0.010) in patients receiving pacemaker therapy for sinus node dysfunction.
RCT (n=2,010)
Effect estimate: HR 1.35 (95% CI 1.07-1.70)
p-value: p=0.010
BACKGROUND: Prolonged QRS duration (QRSd) is an important prognostic indicator for death and heart failure hospitalization in patients with systolic heart failure. The relationship of baseline QRSd to death and heart failure hospitalization in patients with sinus node dysfunction who require pacemaker therapy is unknown. METHODS AND RESULTS: Baseline QRSd from 12-lead ECGs before pacemaker implantation were analyzed in the Mode Selection Trial (MOST), a 6-year, 2010-patient randomized trial of dual-chamber versus ventricular pacing in sinus node dysfunction. Baseline QRSd was > or =120 ms in 23.4% of patients and was associated with older age, lower ejection fraction, cardiomyopathy, and prior heart failure. Adjusted Cox models demonstrated baseline QRSd > or =120 ms was a strong independent predictor of death (hazard ratio 95% CI 1.35 1.07, 1.70, P=0.010) but not heart failure hospitalization. The risk of death increased with increased QRSd from 60 to 120 ms (P=0.002 and hazard ratio 95% CI 1.14 1.05, 1.23 for 10-ms increase in this range) after adjustment for other death predictors. CONCLUSIONS: Baseline QRSd > or =120 ms was associated with increased risk of death during pacemaker therapy for sinus node dysfunction.
Sweeney et al. (Tue,) conducted a rct in Sinus node dysfunction (n=2,010). Baseline QRS duration ≥120 ms vs. Baseline QRS duration <120 ms was evaluated on Death (HR 1.35, 95% CI 1.07-1.70, p=0.010). Baseline QRS duration ≥120 ms was associated with an increased risk of death (HR 1.35; 95% CI 1.07-1.70; P=0.010) in patients receiving pacemaker therapy for sinus node dysfunction.