Severity of Myocardial Infarction

Abstract

Cardiovascular disease constitutes a burden of epidemic proportion,1 and understanding its determinants is essential to designing effective interventions. Doing so requires the ability to track disease burden at the population level. In the United States, without national registries, community surveillance is the method of choice.2 Community surveillance studies are mostly retrospective by design, rely on diagnostic codes for case finding, and require a defined population in which events can be consistently and reliably captured and validated with standardized approaches. Applied to cardiovascular disease, community surveillance measures its burden in communities by tracking the incidence of events, their severity, and their mortality, thereby enabling the appraisal of the components of cardiovascular diseases in a given population.2 Because of the aforementioned methodological requirements, few surveillance studies exist in the United States. They include the Atherosclerosis Risk in Communities (ARIC) Study,3 the Minnesota Heart Survey,4 the Olmsted County Study,5 and the Worcester Heart Attack Study.6 The data from these studies indicate that, although deaths from coronary disease have declined, the incidence of myocardial infarction in the United States has remained mostly stable. Thus, the decline in mortality can be envisioned as reflecting an improvement in survival, which may be mediated by a declining severity of myocardial infarction. Article p 503 The article by Myerson et al7 in this issue of Circulation specifically addresses this important and understudied issue in ARIC between 1987 and 2002. They examined a large, multiracial population and relied on several indicators, including the composite Predicting Risk of Death in Cardiac Disease Tool (PREDICT) score to conclude that the severity of infarction declined over time. Indeed, the proportion of infarctions with major ECG abnormalities, ST-segment elevation, and Q waves decreased, as did biomarker values and the proportion of persons presenting with shock. …