[Diagnostic electrophysiological studies].

Clinical cardiac electrophysiology has evolved over the last decades as a technique to study arrhythmias. Programmed stimulation is a potent tool in assessing the detailed mechanisms of most brady- and tachyarrhythmias as well as a method to judge the efficacy of antiarrhythmic therapy and to stratify patients at risk for the development of life-threatening sustained ventricular arrhythmias. We give an overview of the physiologic mechanisms responsible for paroxysmal supraventricular tachycardias, pre-excited tachycardias as well as sustained ventricular tachycardia in coronary artery disease. Benefit and limitations in assessing the risk for life-threatening tachyarrhythmias in clinically important situations are briefly discussed.