Abstract 15650: Recovery of Cardiomyopathy Following Accessory Pathway Ablation

Abstract

Background: Wolf-Parkinson-White (WPW) can cause significant arrhythmia in addition to left ventricular (LV) dessynchrony and cardiomyopathy, which may be reversible by accessory pathway ablation. Case: A 21-year-old female athletics major college student presents with dyspnea, fatigue and occasional palpitations associated with dizziness. Electrocardiogram (EKG) revealed WPW with left bundle branch block pattern suggestive of right-sided bypass tract (panel A). Transthoracic echocardiogram (TTE) revealed LV ejection fraction (LVEF) 35 - 40% and significant interventricular dessynchrony on M-mode (panel B). Decision-making: It was felt that her symptoms and LV dysfunction are due to QRS widening and possibly arrhythmia caused by the bypass tract, and that ablation is warranted. Electrophysiology study 3-D map revealed 2 insertion points of the bypass tract along the tricuspid annulus (panel C). Ablation was performed initially along the inferior tricuspid annulus, leading to QRS complex narrowing with a change in the delta wave axis. Another activation site was mapped separately to the anterolateral tricuspid annulus; ablation at this site eliminated pre-excitation altogether. Post procedure EKG revealed normalization of the PR interval and diffuse T wave abnormalities likely due to cardiac memory (panel D). Follow-up in 6 weeks revealed an LVEF of 60 - 65% and normal wall motion on TTE with improvement of her symptoms; she was cleared to resume sports. Conclusion: WPW can be associated with significant cardiomyopathy and heart failure due both to arrhythmia and marked LV dessynchrony, which may be reversed by radiofrequency ablation.