Echocardiographic assessment of myocardial work in Wolff-Parkinson-White syndrome: the impact of radiofrequency ablation of the accessory pathway

Background

Wolff-Parkinson-White (WPW) syndrome primarily affects young individuals, increasing the arrhythmic risk. Ventricular preexcitation via an accessory pathway induces ventricular dyssynchrony, and impairment of left ventricular systolic performance.

Recent registry data indicate a persistently increased risk of heart failure in adults with WPW syndrome, even following curative therapy.

Purpose

This study aims to evaluate the impact of radiofrequency ablation of preexcitation on myocardial work and strain in WPW syndrome, clarifying how preexcitation-induced dyssynchrony may contribute to dyssynchronopathy and heart failure.

Methods

A cohort of 20 patients with manifest preexcitation on surface electrocardiogram (mean age 35.8 ± 17.3 years) was included. All patients underwent electrophysiological study and subsequent radiofrequency ablation of the accessory pathway.

The following echocardiographic parameters were assessed before and 24 hours after procedure: left ventricular ejection fraction (LVEF), as well as global longitudinal strain (GLS), myocardial work index (MWI), global work index (GWI), global wasted work (GWW), and global constructive work (GCW). Statistical analysis was conducted in IBM SPSS Statistics 3.0

Results

After the procedure, an increase was observed in myocardial work parameters: GWI: 1768.31 ± 376 mmHg after vs. 1683 ± 298 mmHg before procedure (p = 0.006, 95% CI [-76.24, 246.08]), MWI: 1709.57 ± 398 mmHg after vs. 1637.99 ± 312 mmHg before procedure (p = 0.001, 95% CI [-75.24, 218.39]), GCW: 2122.92 ± 357.47 mmHg after vs. 2055.92 ± 260 mmHg before procedure (p = 0.015, 95% CI [-96.95, 230.95]).

All patients exhibiting preserved LV systolic function before intervention, no statistically significant changes were observed in GLS (-18.3 ± 2.4 after vs. -15.4 ± 2.8 before procedure, p = 0.223) or LVEF (58 ± 6% after vs. 56 ± 4% before procedure, p = 0.399).

Conclusions

Curative radiofrequency ablation improved myocardial work parameters, reflecting enhanced left ventricular systolic function. The lack of significant improvement in GLS, compared to myocardial work, suggests greater sensitivity of the latter to subtle mechanical alterations due to its afterload adjustment. Advanced echocardiographic techniques may further support intervention in asymptomatic patients to prevent systolic dysfunction and heart failure.