Left bundle branch block-induced cardiomyopathy: Myth or reality?

Left ventricular pacing in the treatment of pediatric cardiac dysfunction caused by idiopathic complete left bundle branch block

OBJECTIVE

This study aimed to investigate the feasibility and effectiveness of transthoracic epicardial dual-chamber pacemaker implantation in the treatment of cardiac dysfunction caused by idiopathic complete left bundle branch block (CLBBB) in children.

METHODS

Nine children diagnosed with cardiac dysfunction due to idiopathic CLBBB were included in this study. All patients underwent transthoracic epicardial dual-chamber pacemaker implantation. Cardiac function was evaluated using echocardiography during the follow-up. Additionally, intraventricular synchronization parameters were assessed using two-dimensional speckle tracking echocardiography (STE).

RESULTS

Nine children (mean age, 3.0 ± 2.6 years) were included in this study. The median follow-up duration was 2 (interquartile range, 1-3) years. The cardiac function of all patients recovered to normal levels within 1 year postoperatively. The postoperative QRS duration on electrocardiography (142 ± 21 ms) was significantly shorter than that at baseline (106 ± 12 ms) (p < .05). Cardiac dyssynchrony in patients who manifested preoperatively achieved complete correction after pacemaker implantation. The comparison of preoperative and postoperative (last follow-up visit) synchronization parameters were as follows: longitudinal standard deviation of the time to peak strain, 99.0 ± 41.9 versus 36.8 ± 5.0 ms (p = .004); delay time of peak longitudinal strain, 252.2 ± 131.4 versus 35.0 ± 22.9 ms (p = .002); and longitudinal systolic dyssynchrony index, 2.8 ± 0.8% versus 1.0 ± 0.3% (p = .001), respectively.

CONCLUSION

Transthoracic epicardial dual-chamber pacemaker implantation (with left atrial sensing and left ventricular single-site pacing) can be used for the treatment of cardiac dysfunction caused by idiopathic CLBBB in children.