This article is more than 5 years old. Information may no longer be current.
Radiofrequency catheter ablation improves long-term outcomes in patients with ventricular tachycardia
Click Here to Manage Email Alerts
Patients with recurrent ventricular tachycardia experienced fewer implantable cardioverter defibrillator shocks and ventricular tachycardia episodes at 6 months, and had reductions in amiodarone use and hospitalization during the first 3 years after ablation, according to results of the THERMOCOOL VT trial.
In this prospective, postapproval study, Francis E. Marchlinski, MD, director of electrophysiology for the University of Pennsylvania Health System, and colleagues investigated the long-term safety and effectiveness of radiofrequency catheter ablation using an open-irrigated catheter (Biosense Webster).
Francis E. Marchlinski
The primary acute safety outcome was CV-specific adverse events during ablation and within the first 7 days after ablation. The long-term primary safety outcome was all-cause mortality at 12 months. All-cause and CV-specific mortality during the first 3 years also were evaluated.
Researchers enrolled 249 adults with sustained monomorphic ventricular tachycardia or incessant ventricular tachycardia associated with CAD at 18 U.S. centers between April 2007 and May 2009. All patients were monitored until June 2012. The safety analysis cohort included 233 patients and the efficacy cohort included 224 patients. Of the 224 patients in the efficacy cohort, 184 had available data from the 6-month assessment; 176 for the 1-year assessment, 161 for the 2-year assessment and 141 for the 3-year assessment.
Patient characteristics included left ventricular ejection fraction 10% and any of the following patterns: four or more documented episodes in patients with ICD; two or more documented episodes within 2 months in patients without ICD; incessant ventricular tachycardia due to MI in the previous 3 or more weeks; and/or spontaneous occurrence of symptomatic ventricular tachycardia despite antiarrhythmic medications for ICD intervention.
A majority of the patients were male (94%) and white (92%), and the mean age was 67 years. More than 95% of patients had CAD, 95% had an ICD, 85% had previous MI and 69% had hypertension.
Improved outcomes
According to findings, the CV-specific adverse events rate was 3.9%. The researchers observed one cardiac perforation, two complete heart blocks, three pericardial effusions and three deaths. The median hospital stay after ablation was 2 days.
At 6 months, 62% of patients had no sustained ventricular tachycardia recurrence. In patients with ICDs, the percentage that experienced shocks decreased from 81.2% to 26.8% (P < .0001). Also, the number of patients with normal Hospital Anxiety and Depression Scale scores increased from 48.8% to 69.1% (P < .001).
Marchlinski and colleagues reported all-cause mortality rates of 13.4%, 18.8% and 25.4% at 1, 2 and 3 years after ablation, respectively. Of the 184 patients with available 6-month data, 62% had no ventricular tachycardia recurrence during the first 6 months. According to findings, the steady rate of patient-reported ventricular tachycardia for 1, 2 and 3 years was 22.7%, 29.8% and 24.1%, respectively. Amiodarone use and hospitalization also decreased from 55% and 77.2% pre-ablation to 23.3% and 30.7% at 1 year, 18.5% and 36.7% at 2 years, and 17.7% and 31.3% at 3 years. There was no association between noninducibility and lower mortality at the 3-year follow-up (P = .21).
According to the researchers, further research is needed to explore the mortality benefit of ventricular tachycardia control and the elimination of antiarrhythmic drug therapy.
“The decrease in reported ICD shocks, amiodarone use and long-term hospitalizations suggests a clinically meaningful improvement in [quality of life] that is likely to be reflected in overall patient satisfaction and potential for associated long-term cost containments,” Marchlinski and colleagues wrote.
Findings in context
In a related editorial, Andre d’Avila, MD, PhD, of Hospital Cardiologico, Florianopolis, Brazil, and Sheldon M. Singh, MD, of the Schulich Heart Program at Sunnybrook Hospital, University of Toronto, discussed concern about some of the study’s findings, specifically the 50% rate of arrhythmia recurrence at 2 years and the 25% mortality at 3 years, as well as the lack of association between noninducibility of ventricular tachycardia and long-term survival.
“The disconnect between the acute procedural success rates and poor long-term outcomes raise the possibility that a successful [ventricular tachycardia] ablation procedure may not effect survival at all,” d’Avila and Singh wrote.
Although there was a reduction in total hospitalizations during the study, hospitalization secondary to HF was unchanged after ventricular tachycardia ablation, suggesting that ventricular arrhythmias indicate the presence of progressive HF, according to d’Avila and Singh.
“Multidisciplinary [HF] care should be considered an adjunct to catheter ablation procedures for these complex patients to ensure [HF] medications are optimized, implantable cardiac devices are programmed to avoid right ventricular pacing (noted in 14% of patients in the current study), atrial arrhythmias managed, and assessment for advance [HF] therapies undertaken at an appropriate time,” d’Avila and Singh wrote.
“Such an approach may be necessary to obtain optimal long-term results with [ventricular tachycardia] ablation procedures,” they wrote. – by Tracey Romero
Disclosure: The study was funded by Biosense Webster. Marchlinski reports receiving consultant fees and/or honorarium from Abbott Laboratories, Biosense Webster, Biotronik, Boston Scientific, CardioInsight, Medtronic and St. Jude Medical. Please see the full study for a list of all other authors’ relevant financial disclosures. D’Avila and Singh report no relevant financial disclosures.
Click Here to Manage Email Alerts