Silent myocardial ischemia: A special aspect of coronary artery disease

Abstract

Silent myocardial ischemia is a serious progressive disease which deserves continuous surveillance. It is characterized by painless ST-segment depression based on coronary artery disease. The mechanisms responsible for producing this condition do not differ from stable angina pectoris. The prognostic implications of silent ischemia are not yet completely clarified. However it could be argued that patients die--whether or not angina pectoris is present--because they develop myocardial infarction or ischemic ventricular arrhythmias. Complex ventricular arrhythmias seem to occur not at a higher rate than in patients with angina pectoris. On the other hand there is no doubt about a present arrhythmogenic potential of a silent myocardial ischemia, but there is so far no clinical evidence that the prognostic significance is different to symptomatic myocardial ischemia. In order to reduce or eliminate ischemic episodes intensive combination medical therapy should be used. If symptoms recur or ischemic changes are persistent, consideration should be given to revascularisation. Nevertheless, the optimal way of treating silent ischemia is still to be defined.

Perioperative ST‐segment depression and troponin T release

“…Perioperative myocardial ischaemia with a frequency of up to 94% occurs without signs and asymptomatically. Recurrent silent ischaemia may result in severe cardiac complications and myocardial infarction (6)(7)(8); however, the extent of myocardial damage created by silent myocardial ischaemia (SMI) can not be predicted.…”

“…Compared with different imaging techniques, such as transoesophageal or stress echocardiography, electrocardiography including ST segment analysis has been proved to be a reliable tool in detecting SMI (5). However, the sensitivity of ST segment analysis is limited to about 80% of ischaemic events (3,6).…”