Invasive cardiac electrophysiologic testing: the current state of the art.

DURING the past decade, there has been enormous interest in the use of invasive electrophysiologic testing to evaluate patients with cardiac arrhythmias and conduction disturbances. In this editorial, we present our views on the clinical value of this procedure, ever mindful of our own biases and the knowledge that many important issues in this rapidly expanding area of cardiology remain controversial. The important contributions of invasive testing to the understanding of mechanisms of arrhythmia and drug actions remain unchallenged. Our focus is on the clinical applicability of electrophysiologic testing. Electrophysiologic testing is used to evaluate sinus node function, atrioventricular (AV) conduction and tachyarrhythmias. The number of electrode catheters inserted depends on the nature of the study. In general, at least two catheters are required. However, for more detailed studies, up to five intracardiac catheters may be necessary. In selected patients, left ventricular stimulation may be necessary for proper evaluation.