The Centers for Medicare and Medicaid Services provides public reporting on the quality of hospital care for patients with acute myocardial infarction (AMI). The Centers for Medicare and Medicaid Services Core Measures allow discretion in excluding patients because of relative contraindications to aspirin, β-blockers, and angiotensin-converting enzyme inhibitors. We describe trends in the proportion of patients with AMI with contraindications that could lead to discretionary exclusion from public reporting.