QRS and QTc interval prolongation in the prediction of long-term mortality of patients with acute destabilised heart failure

YObjectives: To quantify the prognostic utility of QRS and QTc interval prolongation in patients presenting with acute destabilised heart failure ( ADHF) to the emergency department ( ED). Design: Prospective cohort study among patients enrolled in the B- Type Natriuretic Peptide for Acute Shortness of Breath Evaluation ( BASEL) study. QRS and QT intervals were measured in 173 consecutive patients with ADHF. QT interval was corrected using the Bazett formula. The primary end point was all- cause mortality during the 720- day follow- up. Results: QRS interval was prolonged (> 120 >=) in 27% of patients, and QTc interval was prolonged (> 440 ms) in 72% of patients. Baseline demographic and clinical characteristics were comparable in patients with normal and prolonged QRS or QTc intervals. A total of 78 patients died during follow- up. Interestingly, the 720- day mortality was similar in patients with prolonged and normal QTc ( 44% vs 42%, p = 0.546), but was significantly higher in patients with prolonged QRS interval than in those with normal QRS ( 59% vs 37%, p = 0.004). In Cox proportional hazards analysis, prolonged QRS interval was associated with a nearly twofold increase in mortality ( HR 1.94, 95% CI 1.22 to 3.07; p = 0.005). This association persisted after adjustment for variables routinely available in the ED. Conclusions: Prolonged QRS interval, but not prolonged QTc interval, is associated with increased long- term mortality in patients with ADHF.