POWDER-AF: Continuing ineffective antiarrhythmic drug therapy after ablation may reduce risk for atrial tachyarrhythmias
CHICAGO — Continuing previously ineffective antiarrhythmic drug therapy after pulmonary vein isolation was associated with lower prevalence of atrial tachyarrhythmias at 1 year, according to results presented at the Heart Rhythm Society Annual Scientific Sessions.
Researchers of the POWDER-AF trial reviewed 153 patients with atrial fibrillation who were previously unsuccessful with antiarrhythmic drug therapy, Mattias Duytschaever, MD, PhD, a specialist at the AZ St. Jan Hospital department of cardiology in Bruges, Belgium, said during a presentation.
If patients were free from AF at 3 months after contact-force guided pulmonary vein isolation, they were randomly assigned to either continue antiarrhythmic drug therapy (n = 77; mean age, 63 years; 74% men) or to discontinue it (n = 76; mean age, 62 years; 72% men). Antiarrhythmic drug therapies included were flecainide, propafenone and sotalol.
Follow-up was completed 3 to 12 months after pulmonary vein isolation. During the follow-up period, clinical visits, 1-day and 7-day Holter monitoring and quality of life questionnaires were administered.
“Our question was very straightforward: In this multicenter randomized trial, would continued use of previously ineffective antiarrhythmic drug therapy reduce atrial tachyarrhythmias in the first year after [pulmonary vein isolation],” Duytschaever said in a presentation.
The primary endpoint was any documented atrial tachyarrhythmia, defined as AF, atrial flutter and atrial tachycardia, that lasted longer than 30 seconds throughout follow-up. Quality of life score, unscheduled clinical visits, repeat ablations and antiarrhythmic drug therapy-related adverse events were the secondary endpoints.
Six patients were lost to follow-up. The primary endpoint occurred in 2.7% (n = 2) of patients who continued antiarrhythmic drug therapy and 21.9% (n = 16) of those who discontinued therapy (P < .001).
Patients who continued antiarrhythmic drug therapy had a lower occurrence of repeat ablation (1.3%) vs. those who stopped therapy (17.1%; OR = 0.06; 95% CI, 0.001-0.46). Researchers also observed lower rates of unscheduled clinical visits in patients who continued therapy (2.6%) compared with those who discontinued therapy (19.7%; OR = 0.11; 95% CI, 0.02-0.49). Quality of life scores were similar in both groups.
In this population, “continued use of previously ineffective drugs significantly reduces recurrence of atrial tachyarrhythmias after pulmonary vein isolation,” Duytschaever said during the presentation. “The strategy of continued use of antiarrhythmic drugs is associated with a lower rate of repeat ablation and a low rate of unscheduled visits without compromising the quality of life. The use of previously ineffective antiarrhythmic drugs after ablation can be seen as an alternative and valid treatment strategy for hybrid rhythm control.” – by Darlene Dobkowski
Duytschaever M, et al. LBCT02-04. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 10-13, 2017; Chicago.
Disclosure: The study was investigator-initiated and funded by Biosense Webster. Duytschaever reports no relevant financial disclosures.