Baseline Characteristics and Risk Profiles of Participants in the ISCHEMIA Randomized Clinical Trial

Abstract

It is unknown whether coronary revascularization, when added to optimal medical therapy, improves prognosis in patients with stable ischemic heart disease (SIHD) at increased risk of cardiovascular events owing to moderate or severe ischemia. OBJECTIVE To describe baseline characteristics of participants enrolled and randomized in the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial and to evaluate whether qualification by stress imaging or nonimaging exercise tolerance test (ETT) influenced risk profiles. DESIGN, SETTING, AND PARTICIPANTS The ISCHEMIA trial recruited patients with SIHD with moderate or severe ischemia on stress testing. Blinded coronary computed tomography angiography was performed in most participants and reviewed by a core laboratory to exclude left main stenosis of at least 50% or no obstructive coronary artery disease (CAD) (<50% for imaging stress test and <70% for ETT). The study included 341 enrolling sites (320 randomizing) in 38 countries and patients with SIHD and moderate or severe ischemia on stress testing. Data presented were extracted on December 17, 2018. MAIN OUTCOMES AND MEASURES Enrolled, excluded, and randomized participants' baseline characteristics. No clinical outcomes are reported. RESULTS A total of 8518 patients were enrolled, and 5179 were randomized. Common reasons for exclusion were core laboratory determination of insufficient ischemia, unprotected left main stenosis of at least 50%, or no stenosis that met study obstructive CAD criteria on study coronary computed tomography angiography. Randomized participants had a median age of 64 years, with 1168 women (22.6%), 1726 nonwhite participants (33.7%), 748 Hispanic participants (15.5%), 2122 with diabetes (41.0%), and 4643 with a history of angina (89.7%). Among the 3909 participants randomized after stress imaging, core laboratory assessment of ischemia severity (in 3901 participants) was severe in 1748 (44.8%), moderate in 1600 (41.0%), mild in 317 (8.1%) and none or uninterpretable in 236 (6.0%), Among the 1270 participants who were randomized after nonimaging ETT, core laboratory determination of ischemia severity (in 1266 participants) was severe (an eligibility criterion) in 1051 (83.0%), moderate in 101 (8.0%), mild in 34 (2.7%) and none or uninterpretable in 80 (6.3%). Among the 3912 of 5179 randomized participants who underwent coronary computed tomography angiography, 79.0% had multivessel CAD (n = 2679 of 3390) and 86.8% had left anterior descending (LAD) stenosis (n = 3190 of 3677) (proximal in 46.8% [n = 1749 of 3739]). Participants undergoing ETT had greater frequency of 3-vessel CAD, LAD, and proximal LAD stenosis than participants undergoing stress imaging. CONCLUSIONS AND RELEVANCE The ISCHEMIA trial randomized an SIHD population with moderate or severe ischemia on stress testing, of whom most had multivessel CAD.

Stable ischemic heart disease: how to keep it that way

“…Of 8518 patients evaluated, 5179 were enrolled in the ISCHEMIA trial. Baseline demographic and clinical characteristics were well balanced with LAD disease in 87% of those in both groups and proximal LAD disease present in 46% and 47% of the invasive and conservative groups, respectively (17). The goals of prescribed medical therapy, achievement of which did not differ in the two groups, were LDL-C less than 70 mg/dL and on a statin, which was achieved by 59% of participants at the last visit; systolic blood pressures less than 140 mmHg, achieved by 77%; aspirin or another antiplatelet agent, achieved by 97%; and not smoking, achieved by 90%.…”

Cardiac magnetic resonance imaging to detect ischemia in chronic coronary syndromes: state of the art

“…4,12,35 For that reason, results from the ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), which investigates whether coronary revascularization, in addition to optimal medical therapy, improves prognosis in patients with CCS and moderate -to -severe myocardial ischemia assessed by noninvasive imaging, are highly anticipated in early 2020. [36][37][38] Stress cardiac magnetic resonance imaging for the assessment of myocardial ischemia Patients referred for CMR for assessing the presence and extent of ischemia undergo either perfusion CMR with a vasodilator (ie, adenosine, regadenoson, or dipyridamole) and gadolinium contrast media (CM) or dobutamine--stress CMR with wall motion analysis. Administration of CM gives the unique opportunity to combine the diagnosis of myocardial ischemia with the determination of myocardial viability (LGE -CMR).…”

Fractional flow reserve as the standard of reference: All that glistens is not gold

“…12 Whether the risk associated with higher ischemic burden can be reduced by revascularization is currently being prospectively investigated in the ISCHEMIA trial. 13 Meanwhile, fractional flow reserve (FFR) in invasive coronary angiography has been validated against quantitative myocardial perfusion positron emission tomography (PET) imaging and non-invasive imaging 14,15 and emerged as a tool to assess lesion-specific ischemia. The severity of FFR has not only been linked to subsequent cardiovascular outcome 16 but more importantly, an FFR-guided PCI strategy resulted in a significant reduction in urgent revascularizations.…”