[Risks and side effects in treatment of supraventricular tachycardia].

Many new antiarrhythmic drugs effective in supraventricular tachyarrhythmia are now available. Since these compounds may lead to serious side-effects, the correct indication for the antiarrhythmic treatment has to be given regarding the ratio of risk and benefit. There is no doubt that aggravation of arrhythmia i.e. acceleration of tachycardia or even degeneration into ventricular flutter (including torsades-de-pointes tachycardia) and fibrillation may be related to the cardiac diagnosis depending on the extent of disease or left ventricular dysfunction and the presenting arrhythmia and possibly the electrophysiological effects of the drug. In general, negative inotropic effects of antiarrhythmic substances are overestimated; they may even be neglected as long as the antiarrhythmic agent leads to effective suppression of the symptomatic ventricular tachyarrhythmia. The best and most important consequence of the CAST study (Cardiac Arrhythmia Suppression Trial) showing an increase in mortality with antiarrhythmic drugs compared with placebo should be that physicians handle antiarrhythmic drugs now with more care than before. The problems with risks and side-effects in antiarrhythmic drug therapy of supraventricular arrhythmias underline the requirement for careful cardiological evaluation and monitoring in all patients receiving such drugs.