• myocardial infarction;
  • quality;
  • geriatrics;
  • performance measurement


Background: Delay in diagnosis of acute myocardial infarction (AMI) may affect quality of care and its assessment.

Objectives: To examine over time the frequency of delay in AMI diagnosis and the effect of this delay on the quality of patient care and its assessment.

Methods: The authors examined the trend in coded admission diagnosis, age, comorbidities, procedures during hospitalization, and discharge status for 42,406 Connecticut Medicare cases with the principal discharge diagnosis of AMI for the time period 1992 through 2001. For 2,583 cases discharged in 1992 and 1993 and for 1,398 cases discharged in 1998 through 2001, the rates of administration of aspirin (ASA) and beta blocker (BB) on admission and discharge, by admission diagnosis, were ascertained.

Results: For patients discharged with the principal diagnosis of AMI over the decade examined, the proportion with this diagnosis on admission fell (59% to 40%, p < 0.001), the proportion with a non–acute coronary syndrome (ACS) admission diagnosis rose (18% to 26%, p < 0.001), and the population aged (proportion older than 85 years of age increased from 16% to 28%, p < 0.001). Patients with ACS as the admission diagnosis more frequently received cardiac catheterization (during 2000–2001, 39% versus 17%, p < 0.001), percutaneous coronary intervention (19% versus 4%, p < 0.001), and evidence-based therapy; during 1998–2001, opportunities to give ASA or BB on admission were fulfilled for 88% versus 73% (p < 0.001), and on discharge, for 87% versus 74% (p < 0.005).

Conclusions: The diagnosis of AMI is delayed after admission for a significant proportion of cases who receive care that is measured to be of lower quality. There is a need to more effectively diagnose and treat these cases with delayed diagnosis and to develop new quality measures to address changes in the characteristics of patients who are hospitalized with AMI.