Ventricular ectopic activity with spontaneous variant angina: frequency and relation to transient ST segment deviation.

This study was performed (1) to assess the frequency of ventricular ectopic activity (ventricular bigeminy, couplets, or ventricular tachycardia) during spontaneous variant angina; (2) to assess the relation between ventricular ectopy and the severity and duration of ischemia; and (3) to evaluate the precise temporal relation between episodes of ischemia and ventricular ectopy. Fifteen ambulatory patients with variant angina (12 men, 3 women, aged 50 +/- 8 [mean +/- SD] years) had Holter monitoring for 24 hours/week for 10 months (total, 10,238 hours of monitoring), from which the following were measured during each episode of ST deviation (elevation or depression): duration of ST deviation (minutes), maximal ST deviation (millivolts), presence of ventricular ectopic activity, and timing of ventricular ectopy in relation to ST deviation. Of 645 episodes of ST deviation, 79 (12.2%) had associated ectopy, almost all of which occurred in three patients. The 79 episodes of ST deviation with ectopy lasted 4.6 +/- 3.3 minutes and averaged 0.16 +/- 0.12 mV, whereas the 566 episodes of ST deviation without ectopy lasted 4.7 +/- 6.1 minutes and averaged 0.17 +/- 0.11 mV (NS in comparison to the 79 episodes with ectopy). Of 489 episodes of ST elevation, 72 (14.7%) were accompanied by ventricular ectopy; of 156 episodes of ST depression, only seven (4.5%) had ectopy (chi 2 = 11.531, p less than 0.001). Of the 79 episodes of ventricular ectopy, almost all appeared during a period of increasing or maximal ST deviation, whereas only two appeared as ST deviation was resolving.(ABSTRACT TRUNCATED AT 250 WORDS)