Clinical Question

For patients with moderate to severe reversible ischemic heart disease, does adding an initial invasive strategy to optimal medical therapy reduce mortality more than optimal medical therapy alone?

Bottom Line

An early invasive strategy for patients with moderate to severe ischemic heart disease does not reduce mortality; at best, it shifts mortality from cardiovascular to noncardiovascular causes for those with multivessel disease. (Level of Evidence = 1b)

Synopsis

The ISCHEMIA trial randomized 5,179 patients with moderate to severe reversible ischemic coronary artery disease to receive initial therapy with angiography plus revascularization (75% percutaneous coronary intervention, 25% bypass surgery) and optimal medical therapy or optimal medical therapy alone. Patients with left main stenosis, an ejection fraction of less than 35%, recent acute coronary syndrome, or angina that could not be treated medically were excluded.

Groups were balanced at the start of the trial and analysis was by intention to treat. Approximately 80% of patients in the early intervention group were revascularized, whereas only 23% of patients were ultimately revascularized because of ineffective medical therapy. The original report found no difference in mortality between groups after 3.2 years. The current report extended the follow-up to a median of 5.7 years. All-cause mortality was identical between groups (hazard ratio [HR] = 1.0; 95% CI, 0.85 to 1.18). Although cardiovascular death was less likely for those in the initial invasive group (HR = 0.78; 95% CI, 0.63 to 0.96), noncardiovascular mortality was more likely (HR = 1.44; 95% CI, 1.08 to 1.91). These mortality numbers were driven by patients with at least 70% obstruction of two or more vessels. For the 48% of patients who did not have multivessel disease, there was no difference in all-cause, cardiovascular, or noncardiovascular mortality between groups.