Abstract
To determine whether repetitive ventricular depolarizations are more commonly precipitated by early compared with late premature ventricular complexes, we analyzed continuous electrocardiographic recordings obtained during the first 10 hours in 38 patients with myocardial Infarction without shock with the Argus/H computer system with editor verification of all premature ventricular complexes. Episodes of repetitive ventricular depolarization were defined as two or more consecutive complexes at a rate of 120 beats/min or greater. Premature ventricular complexes occurring with coupling intervals from the preceding normal complex equal to or less than the Q-T interval of the normal complex were defined as early, and those with longer coupling intervals as late. Among all premature ventricular complexes, early premature ventricular complexes accounted for 38 percent. The average coupling interval of premature ventricular complexes from a preceding normal complex did not correlate with heart rate, blood pressure, infarct size estimated enzymatically, the electrocardiographic locus of Infarction or history of previous Infarction. Twenty-nine patients had a total of 337 episodes of repetitive ventricular depolarizations. Somewhat surprisingly, 78 percent of these episodes, and all episodes in 22 patients, were initiated by late premature ventricular complexes. Thus, repetitive ventricular depolarizations in patients with acute myocardial infarction are often precipitated by late rather than early premature ventricular complexes. © 1978.