Current Treatment Recommendations in Antiarrhythmic Therapy

Over the past decade, various studies have demonstrated that class I antiarrhythmic drugs should be avoided in patients with heart failure, cardiac ischaemia or a previous myocardial infarction. In contrast, class II drugs (beta-blockers) reduce morbidity and may even lower mortality in patients suffering from moderate to severe heart failure. In these patients, careful titration of the drug dosage, frequently during hospital admission, may be necessary. If in the setting of heart failure ventricular arrhythmias are symptomatic and/or sustained, patients can be treated effectively, after appropriate treatment of the underlying disease, with the class III drug amiodarone. Unfortunately, this drug does not lower overall mortality, implying that prophylactic institution of amiodarone is not indicated. Pure class III antiarrhythmic drugs like d-sotalol, ibutilide and dofetilide show a high rate of torsade de pointes. Currently, only ibutilide has been approved for clinically monitored intravenous administration. Class IV drugs, the calcium channel blockers, are still very useful for rate control of atrial fibrillation and conversion or prevention of atrioventricular nodal re-entrant tachycardias and circus movement tachycardias using a (concealed) bypass tract. Finally, an implantable cardioverter defibrillator seems to improve overall survival in patients with life-threatening ventricular arrhythmias. This may imply that an increasing number of patients will be candidates for such a device. However, it will be necessary to await publication of data involving these devices from current ongoing studies.