[Painless episodes of ST segment displacement and the possibility of their prevention in patients with exertion-induced stenocardia].

Sixty patients with stable exercise-induced angina were examined by 24-hour Holter monitoring. It was found that an average of 51.7% of significant episodes of ischemic ST-segment depression failed to be accompanied by anginal episodes during the whole day. The number and length of painless episodes of ST-segment depression exceeded those observed in painful episodes. The range in the values seen in ST-segment depression was great during the episodes, while its threshold values were far stable at the onset of pain. Usage of analyzing cardiac monitors with a signalling system switched on by the preset values of ST-segment depression prevented the evolution of myocardial ischemia and the development of exercise-induced anginal episodes.