Saline-irrigated tip catheter ablation successfully eliminated clinical target ventricular tachycardia in 5 of 8 patients (63%) who had previously failed conventional radiofrequency ablation.
Observational (n=8)
Does ablation using a saline-irrigated tip catheter improve procedural success in patients with ventricular tachycardia resistant to conventional radiofrequency ablation?
A saline-irrigated tip catheter can successfully ablate ventricular tachycardia in a majority of patients who fail conventional radiofrequency ablation.
INTRODUCTION: Radiofrequency (RF) catheter ablation of ventricular tachycardia (VT) may fail if the critical isthmus is located intramyocardially or epicardially. The design of a saline-irrigated tip (SIT) catheter (Thermo-Cool, Cordis-Webster) involves active cooling of the tip electrode, which allows creation of larger ablation lesions. METHODS AND RESULTS: Eight patients (6 men, age 59 +/- 12 years) in whom the clinical target VT (cycle length 430 +/- 97 msec) could not be ablated using a conventional 4-mm tip RF ablation catheter underwent additional attempts to ablate this VT using a SIT catheter. Six patients had an old myocardial infarction, 1 patient had a dilated cardiomyopathy, and 1 patient had a structurally normal heart. Ablation of the clinical target VT using a SIT catheter was attempted from the left ventricle in 6 (septal, posterobasal, and inferior: 2 each) and from the right ventricle in 2 patients (both septal), by entrainment (n = 6), activation (n = 1), or pace mapping (n = 1). A mean of 6 +/- 5 (range 2 to 15) pulses were delivered. Target VT ablation was successful in 5 patients (63%). After successful ablation, at a mean follow-up of 6.5 +/- 4 months and while taking antiarrhythmic drugs, all 5 patients were free of VT recurrences. CONCLUSION: The clinical target VT could be ablated using a SIT catheter in 5 (63%) of the 8 patients in whom ablation using a conventional RF catheter was unsuccessful. In the 2 patients with septal VT, a biventricular approach to mapping and ablation was required.
Nabar et al. (Thu,) conducted a observational in Ventricular tachycardia resistant to conventional radiofrequency ablation (n=8). Saline-irrigated tip (SIT) catheter ablation vs. Conventional 4-mm tip RF ablation catheter was evaluated on Successful target VT ablation. Saline-irrigated tip catheter ablation successfully eliminated clinical target ventricular tachycardia in 5 of 8 patients (63%) who had previously failed conventional radiofrequency ablation.