ISCHEMIA Trial: Was It Worth the Wait?

Rasha Al-Lamee, MBBS, MA, PhD; Alice K. Jacobs, MD


Circulation. 2020;142(5):517-519. 

In This Article

Does Ischemia Matter?

Despite these data, angst remains in the clinical community over withholding revascularization in patients with moderate to severe ischemia for fear of an adverse outcome. It seems biologically plausible that outcomes are most likely to be improved in patients with the most severe disease and that ischemia assessment is a surrogate tool for disease severity stratification. Whereas observational data suggested that the burden of ischemia was important and that revascularization could improve outcomes, data from the COURAGE trials (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) showed that this effect was less clear. The first nuclear substudy included only patients who had both prerandomization and follow-up myocardial perfusion scans.[4] Although patients with ischemia in the percutaneous coronary intervention arm had lower unadjusted risk of MI or death, the difference became nonsignificant once adjusted for baseline risk. The next nuclear substudy of 1381 patients with prerandomization myocardial perfusion scans showed no between-arm difference in death or MI rates.[5] Although guidelines continued to suggest that revascularization should be offered at an earlier stage to patients with the highest ischemia burden, the questions of whether ischemia truly matters and how revascularization affects outcomes remained unanswered. Thus, the National Heart, Lung, and Blood Institute–funded ISCHEMIA trial (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) was undertaken.