ABSTRACT
OBJECTIVES: The relationships between filtered QRS duration and ventricular dyssynchrony were studied. METHODS: We measured filtered QRS duration on signal-averaged electrocardiography and analyzed tissue Doppler imaging in chronic heart failure patients with ejection fraction less than 50%. RESULTS: In 64 patients, interventricular and intraventricular dyssynchronies were observed in 25 and 38 patients, respectively. All patients with interventricular dyssynchrony were associated with intraventricular dyssynchrony. Filtered QRS showed 0.82 and 0.78 of the area under the curve (AUC) in the receiver operating characteristic curve (ROC) for the detection of interventricular and intraventricular dyssynchrony, respectively, with 89.7% and 96.2% specificity and 52.0% and 52.6% sensitivity, with cutoff values of 174 and 153 milliseconds. Specificity and sensitivity as well as AUC were lower in the ROC of QRS duration than filtered QRS duration. CONCLUSION: Filtered QRS duration provided more reliable information to estimate ventricular dyssynchrony in patients with reduced ventricular ejection fraction than QRS duration did.
