IMPORTANT advances have recently been made in the understanding of cardiac arrhythmias. It is the purpose of this review to summarize these advances as they relate to the diagnosis, evaluation, and treatment of chronic recurrent ventricular tachycardia. This review does not concern the evaluation of ventricular tachycardia in the acute setting, ie, associated with acute myocardial infarction, anesthesia, electrolyte imbalance, or drug intoxication. Similarly, it does not concern treatment in terms of termination of acute attacks of tachycardia but rather treatment as it relates to prevention of recurrences.
The diagnosis of ventricular tachycardia requires the observation of at least three wide (duration of at least 0.12 s) QRS beats occurring in a row and at a tachycardiac rate (greater than 100 beats per minute). However, while such a rhythm could be ventricular, it could also be supraventricular, with wide QRS complexes as a result of preexistent bundle-branch block,