Intravenous vernakalant facilitates electrical cardioversion in patients with cardioversion-resistant atrial fibrillation


Cardiome has announced that an independent study conducted by investigators at the University of Leipzig Heart Center, Germany, found that intravenous vernakalant facilitated successful electrical cardioversion (ECV) in patients who had failed to attain sinus rhythm following failed electrical cardioversion (FECV), or who immediately returned to atrial fibrillation after briefly attaining sinus rhythm. The study is published on the journal Europace‘s website. Cardiome did not fund the study, design its protocols or have any role in study implementation or analysis.

The non-randomised study examined if either of two pharmacologic converting agents, vernakalant or amiodarone, facilitated subsequent ECV in 63 patients with atrial fibrillation (n=44; 70%) or FECV (n=19; 30%) after consecutive ECV. Patients were assigned to receive either a single dose of vernakalant (n=33; 52%) or amiodarone (n=30; 48%) prior to another attempt with ECV at the discretion of the treating physician. Ten minutes after completion of the drug infusion, transthoracic ECV was attempted again with a shock that had the same energy as the previous shock. In the event of another episode of atrial fibrillation, no more attempts of ECV were repeated.

The study found that 66.7% of the patients in the vernakalant group (22 of 33 patients) were successfully electrically cardioverted after drug infusion compared to 46.7% (14 of 30 patients) of patients treated with amiodarone (p=0.109). Treatment with vernakalant was also listed as a predictor of successful, drug-facilitated ECV based upon the results of a multivariate analysis (odds ratio 0.057, 95% confidence interval 0.006-0.540, p=0.013). In addition, a subgroup analysis found that patients who had undergone previous atrial fibrillation ablation and who were provided vernakalant had a conversion rate of 66.7% (6 of 9 patients) compared to 11.1% (1 of 9 patients) in the same population who were provided amiodarone (p=0.016). The authors concluded that vernakalant “may therefore be considered as a useful agent for facilitated ECV in cardioversion resistant atrial fibrillation.” The study did not report any major adverse events.

“We are very excited to see the results from this small non-randomised study in a resistant patient population but larger, controlled clinical studies will be necessary to confirm its findings,” said Steen Juul-Möller, Cardiome’s medical director. “These results underline the vernakalant-induced stabilising effect on the atrial wavelets in atrial fibrillation, facilitating cardioversion even in patients with atrial fibrillation relapse after lung vein isolation ablation.” In addition, Juul-Möller commented that “Taken together with the independent data published earlier this year suggesting that challenging post-surgical patients also received a benefit from vernakalant, this new data within resistant patients suggests that physicians who are using vernakalant in their clinical practice show continued high interest to explore its use by expanding scientific evidence.”