64 Non-concomitant Hybrid Ablation Using the Novel Cobra Fusion RF Device Provides Promising Medium Term Outcomes in The Treatment of Longstanding Persistent Atrial Fibrillation

Background Outcomes for catheter ablation of long-standing persistent atrial fibrillation (LsPsAF) are inferior to those of paroxysmal atrial fibrillation and the optimal ablation strategy remains unclear. We describe our experience of non-concomitant hybrid ablation for LsPAF using a novel surgical RF ablation system. Methods Thefirst surgical stage is performed via a right-sided video assisted thoroscopic approach (VATS). The suction based Cobra Fusion RF system (Atricure Inc, West Chester, OH) is used to ablate a ‘box lesion’ and isolate the left atrial posterior wall (LAPW). Patients then return for a staged endocardial mapping procedure with catheter ablation to complete the ‘box’, treat atrial arrhythmia and create a cavo-tricuspid isthmus line. Results Thirty-five patients underwent a VATS procedure with ablation performed in 33 (2 having dense pericardial adhesions). One patient had a fatal CVA post operatively and 5 patients developed transient phrenic nerve palsy. 32 patients (28M/4F) are therefore currently under follow-up: (all values median), age – 65, CHADSVASc – 2, BMI - 30, Left atrial diameter –46.5mm, LVEF –55%, total AF duration – 30 months. Following epicardial ablation acute LAPW isolation with entrance and exit block was demonstrated in 53%. Twenty-one patients have undergone the 2 nd catheter stage after a median of 142 days. The baseline rhythm was sinus rhythm (SR) in 24%, AF in 52% and A. Flutter in 24%. 33% had LAPW isolation at baseline (Figure 1) with further ablation isolating the LAPW (figure 2) in all except one patient, 1 patient required a mitral isthmus line, and 1 patient ablation for right atrial tachycardia. All patients were discharged in SR. Sixteen patients have greater than 3 month’s follow-up (median – 13 months) post 2 nd stage with ECG, clinical review and 7 day ambulatory monitoring at 4, 12 and 24 months. 15 (93%) remain in SR. Three patients required DCCV in the first 3 months and 3 remain on anti-arrhythmic drugs. Conclusions Non-concomitant hybrid AF ablation provides excellent medium term outcomes in the treatment of longstanding persistent atrial fibrillation. Long-term outcomes of the technique and randomised study comparing with catheter ablation alone are needed.