Abstract 16505: Sinus Node Sparing Surgical Hybrid Thoracoscopic Ablation for Inappropriate Sinus Tachycardia: Results of a Prospective Multicenter Registry (the Susruta Registry)

Background: Medical treatment for inappropriate sinus tachycardia (IST) remains suboptimal. Radiofrequency Sinus node Modification (RFSM) has been used for managing drug-refractory symptomatic IST. Although, acute success is reasonable, it is faced with high complications and recurrence rates. A novel Sinus Node sparing surgical thoracoscopic hybrid ablation (SUSRUTA) has been recently proposed. Objective: To report outcomes of SUSRUTA for IST patients from a prospective multicenter registry. Methods: This is a multicenter, prospective registry of patients who received SUSRUTA which is SN sparing hybrid ablation using surgical thoracoscopic video-assisted epicardial ablation comprised of a RF bipolar clamp which was used for sparing the SN region (identified by endocardial 3D mapping) and isolation of superior and inferior vena cava with creation of a lateral line across the crista terminalis during IST with isoproterenol challenge. Gaps in the epicardial lesion set are filled in by endocardial RFA. Patients were treated with post op Colchicine and were enrolled in cardiac rehabilitation program. Results: Of the 139 patients, mean age was 26±4 yrs, 91% women and mean duration of IST was 40±21.5 months. 90% were on ivabradine, 86% on beta-blocker, 77% on calcium channel blocker and 77% were on class IC antiarrhythmic agent. Heart rate post-procedure was significantly lower when compared with pre-procedure (110±10 vs. 64±11 bpm, p<0.0001). After a blanking period of 3 months, normal sinus rhythm was restored in 100% of patients in the hybrid group. Postop pericarditis was the most common complication in 80%(severe-4%), severe bradycardia (HR <35 bpm) in 5%, pneumothorax 3.5% and pleural effusion requiring drainage in 2.1% of cases. One patient required a permanent pacemaker. Hospital length of stay was 4.5±0.8 days. At 1041±541 days follow up 94.5% (131/139) were free of symptoms after a single procedure and the 8 patients required a redo-RF catheter ablation.95% patients are off all preprocedural rate controlling medications Conclusion: SUSRUTA appears to be efficacious and safe for the treatment of symptomatic drug resistant IST.