Ventricular arrhythmias during unstable angina pectoris.

In order to study the occurrence and frequency of ischemia-induced ventricular arrhythmias, we analyzed 105 episodes of spontaneous angina pectoris occurring at rest in 28 hospitalized patients with unstable angina pectoris and proved coronary artery disease. Of 24 patients with serious ventricular arrhythmias during pain, 17 (57%) were arrhythmia-free during monitoring. In the other four patients, 17 of 29 (59%) pain episodes were associated with serious ventricular arrhythmias, and three of these four had serious ventricular arrhythmias during pain-free periods. Each patient tended to manifest the same type of arrhythmia during repeat episodes of pain. It appears that continuous electrocardiogram (ECG) monitoring is important during the initial hospitalization of the patient with unstable angina. The presence of ventricular arrhythmias during pain-free periods indicates a high risk for serious ventricular arrhythmias during episodes of spontaneous pain. These patients should be considered for continued ECG monitoring and antiarrhythmic therapy.