Prognostic Implication of QRS Variability during Hospitalization in Patients with Acute Decompensated Heart Failure

BACKGROUND AND OBJECTIVES Heart failure (HF) patients display more varied QRS duration. We investigated whether QRS variability during hospitalization for acute decompensated HF is associated with poor clinical outcomes after discharge. SUBJECTS AND METHODS One hundred seventy three patients (64% males; age 60±13 years) admitted for acute decompensated HF with severe left ventricular (LV) dysfunction (LV ejection fraction ≤35%) were consecutively enrolled. QRS variability was calculated by the difference between maximum and minimum QRS duration acquired during hospitalization. The prognostic implications on composite endpoints of death or urgent heart transplantation were analyzed. RESULTS Forty-two patients (24.3%) died and three patients (1.7%) underwent urgent heart transplantation during the follow-up of 51±18 months. Patients who reached composite endpoints (n=45) showed greater QRS variability than those who did not (n=128) (20±23 ms vs. 14±14 ms, p=0.046). Patients who had high QRS variability (more than 22 ms; n=36) tended to have a higher event rate than those with QRS variability <22 ms {39% vs. 23%, hazard ratio (HR), 1.88; 95% confidence interval (CI) 1.001-3.539, p=0.05}. Adjusting with other variables, high QRS variability was an independent predictor for composite outcome (HR 1.94; 95% CI 1.023-3.683, p=0.042). CONCLUSION QRS variability measured during hospitalization for acute decompensated HF has a prognostic impact in HF patients with severe LV dysfunction.