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

Area of Science:

• Cardiology
• Electrophysiology

Background:

• Variant angina is characterized by myocardial ischemia due to coronary artery spasm.
• Ventricular arrhythmias are a known complication of acute myocardial ischemia.

Purpose of the Study:

• To determine the frequency of ventricular ectopic activity during spontaneous variant angina.
• To correlate ventricular ectopy with ischemia severity and duration.
• To analyze the temporal relationship between ischemia and ventricular ectopy.

Main Methods:

• Ambulatory Holter monitoring (10,238 hours) in 15 patients with variant angina.
• Analysis of ST deviation (elevation/depression), its duration, and maximal deviation.
• Recording of ventricular ectopic activity (bigeminy, couplets, tachycardia) and its timing relative to ST changes.

Main Results:

• 79 of 645 (12.2%) ST deviation episodes were associated with ventricular ectopy.
• Ventricular ectopy was more frequent during ST elevation (14.7%) than ST depression (4.5%).
• Ectopy predominantly occurred during increasing or maximal ST deviation, rarely during resolution.

Conclusions:

• Ventricular ectopic activity frequently accompanies spontaneous variant angina, particularly ST elevation.
• The timing of ectopy suggests it is triggered by acute ischemia rather than reperfusion.
• These findings highlight the proarrhythmic potential of ischemic episodes in variant angina.