Result and technique consideration of radiofrequency catheter ablation of tachycardia in patients with dextrocardia.

BACKGROUND:Patients with tachycardia, in the context of pre-existing dextrocardia, could benefit from catheter ablation. However, anatomical complexities hinder effective conduct of this procedure. We aimed to retrospectively summarize the clinical characteristics and the safety and efficiency, and recommended the technique considerations. METHODS:Twenty-one cases from 19 patients with tachycardia and dextrocardia, who underwent catheter ablation between 2009 and 2021, were enrolled. All patients underwent echocardiography and computed tomography (CT) to confirm the anatomical malformations. Transseptal puncture was guided by fluoroscopy or intracardiac echocardiography when left atrial access was necessary and the ablation process was guided by three-dimensional (3D) mapping. RESULTS:Six cases exhibited situs solitus while nine cases exhibited situs inversus. Fourteen cases had atrial fibrillation, seven had atrial flutter, and two had atrioventricular reentrant tachycardia (AVRT); two cases had combined atrial fibrillation and atrial flutter. Acute success was achieved in 18 cases (85.7%, 18/21). The 3D mapping system was not employed in the three cases which failed. During long-term follow-up (20.71 ± 21.86 months), eight cases (72.7%, 8/11) of atrial fibrillation with dextrocardia successfully attained sinus rhythm. None of AVRT cases had recurrence. Half of the atrial flutter cases with dextrocardia, especially those with a history of surgical correction for cardiac malformations, underwent recurrence. One case had cardiac tamponade. CONCLUSIONS:Catheter ablation for tachycardia patients with dextrocardia is safe, efficient, and feasible. It is imperative to integrate echocardiography, cardiac computer tomography, and 3D mapping, and apply 3D reconstruction to facilitate the success of catheter ablation.