Cryo Ablation vs. Radiofrequency Catheter Ablation for Ventricular Premature Contractions

Background: Radiofrequency (RF) catheter ablation (CA) is an effective therapeutic strategy in eliminating refractory idiopathic ventricular outflow tract (OT) ventricular arrhythmias (VA). However, early and late recurrences occur commonly. RFCA has also been reported to be associated with collateral damage and pain. The use of Cryo ablation as a safer alternative energy source been previously described. In several reports Cryo was reported to successfully treat VA originating from the OT in the absence of ablation related pain and collateral damage to adjacent structures such as the coronaries. When comparing outcomes and complications of catheter ablation of VA from the papillary muscles of the left ventricle with either Cryo or RF, Cryo was found to be associated with significantly higher success rates and lower recurrence rates than RFCA.

Aim: To compare the outcomes and safety of Cryo vs. RF for PVCs. Methods: Patients with PVC VA will be randomized in a 1:1 fashion to RFCA or Cryo ablation. All procedures will be done using a 3-dimensional mapping system (EnSite™ NavX™ system, St. Jude Medical). Ablation will be performed at sites with earliest activation or at least pacemap exhibiting QRS morphology match of >11/12. Endpoint of procedure will be elimination and non inducibility of the clinical VA. All patients will undergo continuous monitoring for at least 12 hours post procedure and 12 lead Holter and exercise testing 1 month post procedure. Successful ablation will be defined as absence of clinical VA or > 50% reduction in arrhythmia burden on Holter in the absence of anti-arrhythmic medications.