ABSTRACT
Appropriate methodologies are available for assessing in man the effect of the drug on cardiac arrhythmias, left ventricular performance, cardiac conduction, ventricular repolarisation and arrhythmia aggravation. Circulating catecholamines affect myocardial electrophysiological properties and influence the mechanisms that cause arrhythmias. Exercise augments sympathetic tone and is an important tool for the exposure of arrhythmia as well as for the evaluation of antiarrhythmic agents. Studies involving programmed electrical stimulation of the heart have been used to assess the effect of the investigational anti-arrhythmic drug on the induction of monomorphic sustained ventricular tachycardia (VT) in patients with VT or those resuscitated from ventricular fibrillation. Although the most important goal of anti-arrhythmic drug development is the registration of the drug for use in life-threatening ventricular arrhythmias, it is usual to initiate studies in supraventricular arrhythmias at the same time.
