Myocardial infarction, injury up MACE risk

Patients with myocardial infarction (MI) and myocardial injury have a higher risk of developing future cardiovascular events, reveals a study.

“However, in type 2 MI, this apparent risk is reduced by a substantially greater competing risk of non-cardiovascular death,” the investigators said.

The database of Medline, Embase, Central, and Web of Science were systematically searched from 1 January 2007 to 1 July 2025. Prospective studies where cardiac troponin was measured for suspected acute coronary syndrome, diagnoses were adjudicated using the Universal Definition, and both MI and cause-specific mortality were reported for at least 1 year were identified.

The investigators derived subdistribution hazard ratios (HRs) for the competing risk of non-cardiovascular death and performed a meta-analysis with random-effects models. Major cardiovascular events (MACE), defined as MI or cardiovascular death, was the primary outcome. Non-cardiovascular death was the secondary outcome.

Seventeen studies of nine cohorts from nine countries met the eligibility criteria. A total of 120,734 patients (median age 61.0 years, 45.8 percent women) were included. Of these, 11,298 (9.4 percent) had type 1 MI, 3,609 (3.0 percent) had type 2 MI, 5,864 (4.9 percent) had acute myocardial injury, and 5,625 (4.7 percent) had chronic myocardial injury.

The MACE rate was 55.2 percent per 1,000 patient-years (PY) in patients with type 1 MI and 51.7 percent per 1,000 PY in those with type 2 MI, and the rate of non-cardiovascular death was 25.7 and 60.1 per 1,000 PY, respectively. Furthermore, the risk of MACE was 4.82 (95 percent confidence interval [CI], 3.55‒6.57; I2, 84 percent) and 3.36 (95 percent CI, 2.92‒3.86; I2, 0 percent), respectively, compared with those without myocardial injury.

Among patients with acute and chronic myocardial injury, the MACE rate was 47.1 and 44.9 per 1,000 PY and the non-cardiovascular death rate was 67.0 and 46.9 per 1,000 PY in patients with type 1 and 2 MI, respectively. The risk of MACE was 3.24 (95 percent CI, 2.41‒4.36; I2, 59 percent) and 3.03 (95 percent CI, 2.53‒3.62; I2, 20 percent), respectively.

“The Universal Definition classifies MI by aetiology, but its prognostic implications are uncertain,” the investigators said.