Catheter Ablation -> SVT/AVNRT/WPW/AT: -> Ablation Techniques D-PO05 - Poster Session V (ID 39) Poster

D-PO05-150 - Sinus Node Sparing Hybrid Thoracoscopic Ablation Improves Clinical Outcomes In Patients With Inappropriate Sinus Tachycardia: Early Clinical Experience (ID 569)


Background: Medical treatment for inappropriate sinus tachycardia (IST) remains suboptimal. Radiofrequency Sinusnode Modification (RFSM) has been used for managing drug-refractory symptomatic IST. Although, acute success is reasonable, it is faced with high complication and recurrence rates. A novel Sinusnode Sparing Thoracoscopic Hybrid Ablation (SSTHA) has been recently proposed.
Objective: To compare clinical outcomes of RFSM vs SNSTHA in IST patients.
Methods: This is a multicenter, prospective non-randomized study comparing SSTHA combined with concomitant endocardial 3D mapping with RFSM. SSTHA comprised of a thoracoscopic 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. RSM was performed either by endocardial and/or epicardial mapping and ablation at the site of earliest atrial activation during IST. Isoproterenol challenge was used in both scenarios.
Results: 100 patients were studied (SSTHA: 50, RFSM: 50), mean age 22.8 yrs, 82% women and mean duration of IST was 38±20 months. Prior RFA of slowpathway (30% vs 24%), flutter (10 vs 0 %) in RFSM and SSTHA respectively. RFSM underwent a 2.54±0.6 procedures with epicardial mapping and ablation in 48% in the RF group. There was no significant difference in baseline heart rate (HR) between both groups. HR post-procedure was significantly lower in the hybrid group. (61±11 vs. 82±16 bpm, p<0.0001). 28% of RFSM had acute complications (14% phrenic nerve palsy; 10% severe pericarditis; 4% groin hematomas) vs 14% of SSTHA had severe pericarditis. At 12±2 months follow up 100% in the hybrid group were free of symptoms after a single procedure compared with 66% in the RF group (mean 2.44±0.6 procedures). Severe sinus node dysfunction with a permanent pacemaker was needed in 48% of RFSM vs 0% of SSTHA (p<0.0001). Permanent PN palsy was also seen in 8% and chronic pericarditis in 10% of RFSM.
Conclusion: SSTHA appears to be a more efficacious and safer option than RFSM in patients with symptomatic drug resistant IST.