Successful radiofrequency catheter ablation of an anteroseptal accessory pathway in cardiac dextroposition presenting with aborted sudden cardiac death: a case report.

BACKGROUND: Cardiac dextroposition involves a rightward shift of a normally configured heart, setting it apart from mirror-image dextrocardia. This anatomical variant can alter typical thoracic relationships, rendering conventional fluoroscopic reference points unreliable and increasing the complexity of electrophysiological procedures.

CASE SUMMARY: A 57-year-old man was admitted following an out-of-hospital ventricular fibrillation arrest attributed to pre-excited atrial fibrillation. Chest radiography identified rightward displacement of the heart's silhouette. Further diagnostic imaging confirmed cardiac dextroposition without abnormalities in atrioventricular or great-vessel orientation, thus distinguishing it from mirror-image dextrocardia. Electrophysiological study revealed that mapping the anteroseptal accessory pathway was complicated by altered fluoroscopic landmarks. Successful radiofrequency ablation was achieved with the aid of three-dimensional electroanatomical mapping and intracardiac echocardiography, resulting in the elimination of pre-excitation without causing atrioventricular nodal injury.

DISCUSSION: The integration of advanced imaging modalities facilitated accurate localization and ablation, despite the abnormal cardiac position. This case demonstrates that even in the setting of significant anatomical displacement, safe and effective ablation of anteroseptal pathways can be accomplished through the application of multimodal mapping techniques.