Radiofrequency catheter ablation (RFCA) reduced implantable cardioverter-defibrillator (ICD) shocks and ventricular tachycardia (VT) episodes, and improved quality of life after 6 months, according to research published in the Journal of the American College of Cardiology.
Patients with sustained VT have an increased risk of recurrent episodes and sudden cardiac death. Researchers evaluated long-term safety and effectiveness of RFCA using an open-irrigated catheter.
“Results of this study indicate that, in patients with recurrent VT associated with coronary artery disease, RFCA provides dramatic short-term and maintains steady long-term nonrecurrence rates over 3 years, with an acceptable procedural safety profile,” the authors wrote.
The THERMOCOOL VT (NaviStar ThermoCool Catheter for Endocardial RF Ablation in Patients With Ventricular Tachycardia) study included 249 patients (mean age: 67.4 years) with sustained monomorphic VT associated with coronary disease. Researchers analyzed patients for cardiovascular-specific adverse events within 7 days of treatment, hospital duration, 6-month sustained monomorphic VT recurrence, quality of life as measured by the Hospital Anxiety and Depression Scale, and amiodarone use, and long-term survival at 1, 2, and 3 years.
The rate of cardiac adverse events was 3.9%, and the noninducibility of targeted VT was successful in 75.9% of patients with a median hospitalization after ablation stay of 2 days.
At 6 months, 62.0% of the patients had no monomorphic VT recurrence and the proportion of patients with ICD shocks decreased from 81.2% to 26.8% (P<.0001). VT frequency in ICD was reduced by at least 50% in 63.8% of patients. Quality of life was also improved with normal Hospital Anxiety and Depression scores increasing from 48.8% to 69.1% (P<.001).
VT rates, self-reported by patients, remained consistent for 1, 2, and 3 years, at 22.7%, 29.8%, and 24.1%, respectively. A similar effect was seen in amiodarone use, with reductions from 55.0% to 23.3% at 1 year, 18.5% at 2 years, and 17.7% at 3 years. These steady 3-year nonrecurrence rates and reduced amiodarone use, along with fewer hospitalizations, indicate potential for improved long-term outcomes.
While RFCA does not negatively affect all-cause mortality rates (13.4%, 18.8%, and 25.4% at 1, 2, and 3 years post-ablation, respectively), the authors noted, “additional investigations are needed to compare various VT ablation strategies and determine whether this type of procedure reduces mortality rates over long-term follow-up.”
Marchlinski FE, Haffajee CI, Beshai JF, et al. Long-term success of irrigated radiofrequency catheter ablation of sustained ventricular tachycardia: post-approval THERMOCOOL VT trial. J Am Coll Cardiol. 2016; 67(6):674-683. doi: 10.1016/j.jacc.2015.11.041.