Introduction: Transvenous cryoablation has proven to be safe and effective for the treatment of supraventricular arrhythmias. The aim of this prospective study was to report the feasibility and safety of catheter-based cryoablation for the treatment of postinfarction and idiopathic ventricular tachycardia (VT).
Methods and results: Catheter-based cryoablation was performed in 17 patients (15 men, 58 +/- 18 years). VT occurred after a prior myocardial infarction in 10 and was idiopathic in 7 patients. Cryoablation was performed with a 10-F, 6.5-mm tipped catheter. The ablation site was selected using entrainment mapping techniques for postinfarction VT. The site of the earliest activation time with optimal pace mapping was used for ablation of idiopathic VT. All targeted VTs (12 postinfarction and 7 idiopathic) were acute successfully ablated after a median number of 2 applications of 5 minutes with an average temperature of -82 +/- 4 degrees C. Mean procedure and fluoroscopy times were 204 +/- 52 and 52 +/- 20 minutes for postinfarction VT and 203 +/- 24 and 38 +/- 15 minutes for idiopathic VT. No cryocatheter or cryoenergy complications were observed. After a follow-up of 6 months, 4 of the 10 patients with postinfarction VT had a recurrence. In 1 of the 7 patients with idiopathic VT the index arrhythmia recurred.
Conclusion: In this small patient population, catheter-based cryoablation of VT was safe and effective. Future studies are needed to evaluate the effect of cryothermy in a larger group of patients, especially those with postinfarction VT.