Result and Technique Consideration of Radiofrequency Catheter Ablation of Tachycardia in Patients with Dextrocardia

Introduction: Patients with tachycardia and dextrocardia could benefit from catheter ablation. However, anatomical complexities create challenges for that. We aimed to retrospectively summarize the clinical characteristics and the safety and efficiency, and recommended the technique considerations of these patients. Methods and Results: 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 mapping. Six cases exhibited situs solitus while nine cases exhibited situs inversus. Fourteen cases exhibited atrial fibrillation, seven cases exhibited atrial flutter, and two cases exhibited atrioventricular reentrant tachycardia (AVRT)；two cases exhibited atrial fibrillation combined with atrial flutter. Acute success was achieved in 18 cases (85.7%, 18/21). The three-dimensional 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 treatment for heart malformations, underwent recurrence. One case had tamponade. Conclusion: Catheter ablation for tachycardia patients with dextrocardia, is safe, efficient, and feasible. It is imperative to integrate echocardiography, cardiac computer tomography, and three-dimensional mapping, and apply three-dimensional reconstruction to facilitate the success of catheter ablation.