[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address 35.172.195.49. Please contact the publisher to request reinstatement.
[Skip to Content Landing]
Original Investigation
February 27, 2019

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

Author Affiliations
  • 1Cardiovascular Clinical Research Center, New York University School of Medicine, New York, New York
  • 2Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina
  • 3Royal Brompton Hospital, London, United Kingdom
  • 4Northwick Park Hospital, London, United Kingdom
  • 5VA New England Healthcare System Boston, Boston, Massachusetts
  • 6Columbia University Medical Center, New York, New York
  • 7Cardiovascular Research Foundation, New York, New York
  • 8St Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
  • 9Canadian Heart Research Centre, Toronto, Ontario, Canada
  • 10Hospital Universitario La Paz, Instituto de Investigación Hospital Universitario La Paz, Madrid, Spain
  • 11Green Lane Cardiovascular Services, Auckland Hospital, Auckland, New Zealand
  • 12Associazione Nazionale Medici Cardiologi Ospedalieri Research Center, Florence, Italy
  • 13Weill Cornell Medicine, New York, New York
  • 14New York-Presbyterian Hospital, New York, New York
  • 15Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
  • 16Cedars-Sinai Medical Center, Los Angeles, California
  • 17St Louis University School of Medicine, St Louis, Missouri
  • 18Duke University Medical Center, Durham, North Carolina
  • 19University of Missouri-Kansas City School of Medicine, Kansas City, Missouri
  • 20All India Institutes of Medical Sciences, New Delhi, Delhi, India
  • 21The Cardinal Stefan Wyszyński Institute of Cardiology, Warsaw, Poland
  • 22Dayanand Medical College and Hospital, Ludhiana, Punjab, India
  • 23E. Meshalkin National Medical Research Center, Ministry of Health of the Russian Federation, Novosibirsk, Russia
  • 24National Heart, Lung, and Blood Institute, Bethesda, Maryland
  • 25Stanford University School of Medicine, Stanford, California
JAMA Cardiol. 2019;4(3):273-286. doi:10.1001/jamacardio.2019.0014
Key Points

Question  What were the characteristics of International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial participants, and did qualification by stress imaging or nonimaging exercise tolerance test influence risk profiles?

Findings  In this analysis of randomized clinical trial data from the ISCHEMIA trial, randomized participants (n = 5179) were a median age of 64 years, 41% had diabetes, 19% had prior myocardial infarction, and 90% had prior angina. Stress imaging was the qualifying test for 75% (86% with moderate or severe ischemia); of those with coronary computed tomography angiography, 79% had multivessel, 87% had left anterior descending coronary artery, and 47% had proximal left anterior descending coronary artery disease.

Meaning  The International Study of Comparative Health Effectiveness With Medical and Invasive Approaches trial randomized stable patients with moderate or severe ischemia and predominantly multivessel and/or left anterior descending coronary artery disease

Abstract

Importance  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.

Trial Registration  ClinicalTrials.gov Identifier: NCT01471522

×