The Effect of Accessory Pathway Location on Cardiac Function in Adult Patients with Wolff–Parkinson–White Syndrome

Abstract

Introduction. The relationship between ventricular pre-excitation and left ventricular dysfunction has been described in the absence of sustained supraventricular tachycardia in a series of case reports. However, there have been no systematic studies about the effect of ventricular pre-excitation on cardiac function in adult patients with different accessory pathway locations. Methods and Results. Patients were divided into four groups based on the type and location of their accessory pathway: septal, right free wall, left free wall, and concealed. N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, electrocardiogram recordings, electrophysiological properties, and transthoracic echocardiographic data (septal-to-posterior wall motion delay (SPWMD) and interventricular mechanical delay (IVMD) indicating intraventricular and interventricular dyssynchrony) were compared before and after successful ablation. Before radiofrequency catheter ablation, left ventricular ejection fraction (LVEF) was significantly lower in patients with septal and right free wall accessory pathways. Within three months after radiofrequency catheter ablation, NT-proBNP levels decreased, left ventricular function improved, and intraventricular left ventricular dyssynchrony disappeared. There was a negative correlation between initial LVEF with initial QRS duration and initial SPWMD. Notably, SPWMD had a stronger correlation with LVEF than initial QRS duration. Conclusions. Anterograde conduction with a septal or right free wall accessory pathway may cause left ventricular dyssynchrony and impair left ventricular function. Intraventricular left ventricular dyssynchrony seems to be responsible for the pathogenesis of left ventricular dysfunction. Radiofrequency catheter ablation results in decreased NT-proBNP levels, normalized QRS duration, mechanical resynchronization, and improved left ventricular function.

Resolution of severe cardiomyopathy after catheter ablation of an anteroseptal accessory pathway: A case report

“…This improvement can be explained by resolution of the left bundle branch pattern of activation and resultant reverse remodeling. A recent study exploring the relationship between AP location and LV dysfunction noted that LV function was significantly lower in WPW patients with septal and right free wall accessory pathways (Zhang et al, 2021). Our patient was being evaluated for possible heart transplantation when she presented to us and undergoing CA resulted in resolution of her cardiomyopathy.…”

“…Although catheter ablation (CA) of the accessory pathway is an established treatment for symptomatic WPW syndrome, its utility in asymptomatic patients remains unclear. A recent study involving 80 patients with WPW syndrome without tachyarrhythmia noted that left ventricular ejection fraction (LVEF) was significantly lower in patients with septal and right free wall accessory pathways, and CA of the accessory pathway (AP) resulted in mechanical resynchronization and improved LV function within 3 months (Zhang et al, 2021). We report a patient with WPW syndrome without sustained tachyarrhythmia who underwent radiofrequency catheter ablation (RFCA) achieving normalization of left ventricular systolic function.…”