5202Zero- or near-zero fluoroscopy radiofrequency catheter ablation for aortic sinus cusp idiopathic ventricular arrhythmias

Background Complete elimination of fluoroscopy during radiofrequency catheter ablation (RFCA) of idiopathic ventricular arrhythmias (IVA) originating from aortic sinus cusp (ASC) may be challenging, requires confirmation of coronary arteries ostia and could be associated with potential risk of collateral damage and severe complications. Purpose To validate the implementation, feasibility, learning curve, safety and efficacy of zero-fluoroscopy (ZF) approach in centers using near-zero fluoroscopy (NOX) approach for RFCA of idiopathic premature ventricular complexes/ventricular tachycardias (PVCs/VTs) from ASC. Methods From 2012 to 2018, we prospectively enrolled 106 consecutive patients (age: 49±19, males: 58%, children: 7%, 108 PVC/VT focuses from ASC, PVCs/24h: 23808±22006) with ASC-IVA. Patients were unselected and referred for ZF or NOX approach using three dimensional electroanatomic system- 3D EAM without intracardiac or transesophageal echocardiography. The choice of ZF and NOX was based on the first operator experience and from 2014 three experienced operators and three fellows performed ZF as an intention-to-treat approach. The peri-procedural, short-term outcome as well as learning curve of ZF in ASC were evaluated with documentation of reasons for cross-over to NOX approach. Results Out of 108 focuses there were majority of left coronary cusps and left/right junctions sites of origin [other rare locations: right coronary cusp (n=7); non-coronary cusp, n=6)]. On intention-to-treat 61/76 (80%) cases were completed without fluoroscopy in ZF-approach. Additionally, 30/30 (100%) cases were completed with NOX. The main reasons for fluoroscopy use in ZF approach (conversion to NOX) were: the need for elective valsalvography plus coronary angiography (n=6), urgent coronary angiography due to validation of transient uncomplicated coronary spasms and ST elevation (n=2), catheter stability checking (n=2), femoral access site confirmation (n=1) and navigation problem (n=1). No significant differences were found in the acute and short-term success rates between ZF and NOX (90% vs 88%, P=NS) and no major complications occurred. The procedure time, fluoroscopy time and ablation time were 66.8±26.9; 3.6±7.2 and 7.3±5.5 min, respectively. The gathering experience of ZF approach, computer-assisted ECG analysis and 3D-EAM reconstruction of aortic root and coronary artery ostia resulted in significant reduction of NOX approach between early and late period [median (n=53): 2012–2016 vs 2017–2018, 40/53 (76%) vs 5/53 (8%), p<0.001]. Conclusion ZF can be completed in majority of patients with ASC-IVA especially after appropriate training and operators' experience with NOX. ZF approach guided by 3D-EAM is feasible, safe, and effective for treatment of ASC-IVA with importance of training and preprocedural imaging for exclusion of coronary anomalies or validation of coronary arteries ostia by 3D-EAM.