Vernakalant – class IIIa

Vernakalant – class IIIa

Vernakalant is a class IIIa antiarrhythmic agent as per the Modernized Classification of Cardiac Antiarrhythmic Drugs [1]. The class effect is voltage dependent K+ channel blocker. Specifically, it is a Kv1.5 channel–mediated, ultrarapid K+ current (I_Kur) blocker, which is atrium specific.

Atrium-specific actions of vernakalant are as follows:

• Increase in action potential recovery time
• Increase in refractory period
• Decreased reentrant tendency

The drug is used for immediate conversion of atrial fibrillation. It can cause mild QTC prolongation. Hence caution is needed if other QT prolonging drugs have been administered.

It is avoided in those with hypotension and severe aortic stenosis. It can be used in the presence of mild heart failure, NYHA (New York Heart Association) class I and II as per the 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS [2].

References

1. Ming Lei, Lin Wu, Derek A Terrar, Christopher L-H Huang. Modernized Classification of Cardiac Antiarrhythmic Drugs. Circulation. 2018 Oct 23;138(17):1879-1896.
2. Paulus Kirchhof, Stefano Benussi, Dipak Kotecha, Anders Ahlsson, Dan Atar, Barbara Casadei, Manuel Castella, Hans-Christoph Diener, Hein Heidbuchel, Jeroen Hendriks, Gerhard Hindricks, Antonis S Manolis, Jonas Oldgren, Bogdan Alexandru Popescu, Ulrich Schotten, Bart Van Putte, Panagiotis Vardas, ESC Scientific Document Group. 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS. Eur Heart J. 2016 Oct 7;37(38):2893-2962.