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QRS duration, an indirect reflection of ventricular synergy, is not altered in decompensated heart failure.

QRS duration is frequently used to identify left ventricular dyssynchrony and is a primary qualification for cardiac resynchronization therapy. While QRS duration can be wider with higher heart rates due to aberrant conduction, there is little information on fluctuations of QRS duration due to decompensated heart failure, which is relevant with regard to optimal timing to assess patients for cardiac resynchronization therapy (CRT). Therefore, we sought to identify and characterize fluctuations of QRS duration during inhospital treatment for acute decompensated heart failure (ADHF).We analyzed the medical records of all patients admitted to our cardiology service for ADHF. Demographic and clinical data were obtained including analysis of initial and discharge electrocardiogram for QRS duration and determination of left ventricular systolic function. Data were obtained on 107 patients. There was no significant difference in QRS duration from admission to discharge during which patients' clinical status improved from ADHF to the compensated state. Subgroup analysis also did not reveal significant differences in QRS duration in this patient population.QRS duration did not change significantly in these patients during acute heart failure exacerbation or its resolution.