antiarrhythmics

The antiarrhythmics are one of the classes of medicines used in cardiology to restore a regular heart rhythm. The aim is to achieve a normal "sinus" rhythm. They are prescribed, for example to patients with problems such as tachyarrhythmia, in which the heart beats are irregular in frequency (increased) and contractions.

The antiarrhythmics act on the atrium in, for example, atrial fibrillation, or on the ventricle in ventricular extrasystoles or to prevent ventricular tachycardia. The most widely used classification since 1970 is the classification produced by Vaughan Williams. This divides the antiarrhythmics into four classes:

• Class I antiarrhythmics which interfere with the sodium channel;
• Class II antiarrhythmics are the beta blockers;
• Class III antiarrhythmics block the potassium channels;
• Class IV antiarrhythmics are the calcium blockers.

Source: Interview with Dr Joel Kerjean, cardiologist, Angers, 20 June 2011