On 23 September, Cardiome Pharma announced publication of positive data from an open label study in patients with atrial fibrillation that compared treatment with vernakalant intravenous (IV) to oral propafenone and oral flecainide.
Patients treated with vernakalant achieved conversion to normal sinus rhythm in a median time of 12 minutes compared to 151 minutes for the propafenone group and 162 minutes for the flecainide group (p<0.01). These results appeared in the current issue of the Journal of Atrial Fibrillation.
“Vernakalant IV, with its fast onset of action, is a well-tolerated and effective alternative to propafenone or flecainide in this patient population,” said Diego Conde, chief of Cardiovascular Emergency Care Section, Instituto Cardiovascular de Buenos Aires, Argentina. “The significant advantage in time to conversion to normal sinus rhythm with vernakalant compared to propafenone or flecainide, that leads to a reduction in hospital stay-length, may result in patient benefits.”
Patients with symptomatic recent onset atrial fibrillation (less than 48 hours duration) without structural heart disease or haemodynamic instability were eligible for the study. Subjects received a single oral dose of 600mg of propafenone (N=50), a single oral dose of 300mg of flecainide (N=50), or vernakalant IV (N=50) in an initial dose of 3.0 mg/kg for 10 minutes and an additional 2 mg/kg if atrial fibrillation had not resolved within 15 minutes.
The conversion rate approximated 80% in both the propafenone and flecainide groups at eight hours versus 90% in the vernakalant group at two hours. This difference was not statistically significant at eight hours. In addition to the more rapid time to cardioversion, patients treated with vernakalant IV experienced a significantly shorter median hospital length of stay, 243 minutes (interquartile range [IQR], 190-276) versus 422 minutes (IQR, 341- 739) for the patients treated with propafenone and 410 minutes (IQR, 330-727) for the patients treated with flecainide (p<0.01). No adverse events were reported.