Review of the ISCHEMIA Trial
Journal of Clinical Physiology
The ISCHEMIA Trial The ISCHEMIA (International Study of Comparative Effectiveness with Medical and Invasive Approaches) is a largest clinical trial of comparing invasive with conservative treatment strategy in stable ischemic heart disease (SIHD). 1) In ISCHEMIA, 5,179 patients with SIHD who had moderate to severe ischemia on imaging testing or stress electrocardiogram, at least 1 coronary stenosis >50% in a major coronary artery, and no significant left main coronary artery disease (CAD) on
... puted tomography (CT) angiography, were randomly assigned to an initial invasive strategy with optical medical therapy (OMT) or an initial conservative strategy of OMT. The ISCHEMIA is not a study to compare coronary revascularization versus no revascularization, but a study to evaluate clinical benefits of the early invasive approach. In fact, 28% of patients in the conservative group underwent catheterization within 4 years. It is also important to know that the ISCHEMIA was not a percutaneous coronary intervention (PCI) trial, in which more than quarter of revascularization was performed by coronary artery bypass grafting. Major exclusion criteria of the trial were followings: significant left main CAD, left ventricular ejection fraction <35% or New York Heart Association class III to IV heart failure, unacceptable angina, acute coronary syndrome within 2 months, and estimated glomerular filtration rate <30 ml/min/1.73 m 2 . Because of the slow recruitment, the inclusion criteria were amended to include patients according to the evidence of ischemia evaluated by stress electrocardiogram. 2) In the ISCHE-MIA trial, 1,218 of 7,168 (17%) patients with significant ischemia on non-invasive testing had no obstructive epicardial CAD, indicating that ischemia evaluation on functional tests is often difficult. The randomized cohort had a high burden of cardiovascular risk factors (male 77%, hypertension 73%, and diabetes mellitus 42%), while the patients were relatively young (mean age of 64 years) and left ventricular ejection fraction was well preserved (median 60%, interquartile range 55−65). The estimated cumulative incidence of primary composite outcome of cardiovascular death, myocardial infarction (MI), and hospitalization for either unstable ABSTRACT The ISCHEMIA (International Study of Comparative Effectiveness with Medical and Invasive Approaches) was highly anticipated study in the field of cardiology. This article briefly provides a review of the ISCHEMIA trial and better understanding regarding coronary revascularization in patients with stable ischemic heart disease.