Cardiologistsʹ practices compared with practice guidelines: Use of beta-blockade after acute myocardial infarction

Objective. Our purpose was to measure cardiologistsʹ level of adherence to guidelines for long-term use of beta-adrenergic blocker therapy after acute myocardial infarction. Background. Beta-blocker therapy after acute myocardial infarction has been shown to reduce the incidence of reinfarction and associated mortality. To learn about cardiologistsʹ use of this therapy after hospital discharge and their level of adherence to American College of Cardiology guidelines, we analyzed insurance claims from 17 network-model health plans located throughout the United States. Methods. The study group included 150 cardiologists who had contracts with one of the health plans and their 280 patients who were plan members (excluding Medicare enrollees) and received inpatient treatment for acute myocardial infarction that did not include revascularization during 1992. These patients accounted for 307 separate hospital admissions. Insurance claims were used to measure beta-blocker usage and to identify possible contraindications. Results. Forty-three percent of the cases (131 of 307) involved apparent deviations from the guidelines: 11% of cases (35 of 307) involved possible errors of commission (beta-blocker given in the presence of contraindication) and 31% (96 of 307) errors of omission (beta-blocker not given in the absence of contraindication). Of the 185 patients who were eligible for the therapy (no contraindications), only 48% (89 of 185) were treated. Conclusions. Cardiologists currently exhibit low level of compliance with their specialtyʹs guidelines for postinfarction beta-blockade. Slightly fewer than 50% of the study patients who were eligible for treatment actually received beta-blocker after hospital discharge. This result, combined with the drugʹs known level of effectiveness in preventing recurrent myocardial infarction, suggests that increased use could avert not, vert, similar 1,900 deaths annually nationwide.