The predictive value of QRS duration in response to levosimendan therapy in patients with decompensated heart failure.
ABSTRACT We aimed to investigate the role of QRS duration on the surface electrocardiogram (ECG) in predicting response to levosimendan therapy in patients with acute systolic heart failure.
Patients with an ejection fraction (EF) lower than 35% who required intravenous inotropic support despite optimal heart failure therapy were included in this study. Patients were divided into two groups according to QRS durations on ECG. Group 1 (n=16) included patients with a QRS duration equal to or shorter than 120 ms and group 2 (n=14) included patients with a QRS duration longer than 120 ms. New York Heart Association (NYHA) functional class, plasma BNP levels and echocardiographic measurements were compared within and between groups before and after the infusion.
In both groups statistically significant improvement was observed in NYHA class, plasma BNP levels and left ventricular end-systolic diameter after the levosimendan infusion compared to baseline (P < 0.025). In addition, in group 1 patients, left atrial diameter, left atrial volume, left ventricular end-diastolic diameter, left ventricular end-diastolic volume, left ventricular end-systolic volume (LVESV), left ventricular EF, mitral E velocity, mitral annular Aa and Sa parameters improved after the infusion compared to the baseline values (P < 0.025). Comparison of both groups revealed improvement of NYHA class, an increase of left ventricular EF and a signficant decrease of LVESV after levosimendan in group 1 (P < 0.05).
QRS duration on ECG may be used as a practical bedside indicator in estimating short-term response to levosimendan therapy.