Journal Articles
Abstract:
Transient myocardial ischemia (TMI), a condition in which blood flow to the heart is temporarily restricted, has been recognized as an important measure of cardiovascular disease activity. Episodes of TMI are associated with an increased risk of adverse cardiac events, are relatively common in patients with coronary artery disease, and are predominantly asymptomatic. These asymptomatic episodes of TMI, which may be triggered by strenuous physical activity or by daily activities involving little physical effort, represent a condition known as silent myocardial ischemia (SMI). Although the unfavorable prognosis associated with symptom-related TMI, commonly referred to as angina pectoris (AP), has been well studied, the independent prognostic value of SMI has not been adequately addressed. Some studies have reported that SMI has independent prognostic significance, while other studies have concluded that the prognostic significance of TMI is the same whether it is SMI or AP. Methodological limitations of past research, including poorly defined patient characteristics, inadequately defined TMI, and insufficient follow-up periods, have contributed to conflicting results. This review examines the prognostic importance of TMI and specifically addresses the independent contribution of SMI over and above that of AP.