Quality of care for acute myocardial infarction in 58 U.S. emergency departments

Abstract

Objectives: The objectives of this study were to determine concordance of emergency department (ED) management of acute myocardial infarction (AMI) with guideline recommendations and to identify ED and patient characteristics predictive of higher guideline concordance.

Methods: The authors conducted a chart review study of ED AMI care as part of the National Emergency Department Safety Study (NEDSS). Using a primary hospital discharge diagnosis of AMI (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM], codes 410.XX), a random sample of ED visits for AMI in 58 urban EDs across 20 U.S. states between 2003 and 2006 were identified. Concordance with American College of Cardiology/American Heart Association (ACC/AHA) guideline recommendations was evaluated using five individual quality measures and a composite concordance score. Concordance scores were calculated as the percentage of eligible patients who received guidelines-recommended care. These percentage scores were rescaled from 0 to 100, with 100 indicating perfect concordance.

Results: The cohort consisted of 3,819 subjects; their median age was 65 years, and 62% were men. The mean (± standard deviation [SD]) ED composite concordance score was 61 ± 8), with a broad range of values (42 to 84). Except for aspirin use (mean concordance, 82), ED concordance scores were low (beta-blocker use, 56; timely electrocardiogram [ECG], 41; timely fibrinolytic therapy, 26; timely ED disposition for primary percutaneous coronary intervention [PCI] candidates, 43). In multivariable analyses, older age (beta-coefficient per 10-year increase, -1.5; 95% confidence interval [CI] = -2.4 to -0.5) and southern EDs (beta-coefficient, -5.2; 95% CI = -9.6 to -0.9) were associated with lower guideline concordance, whereas ST-segment elevation on initial ED ECG was associated with higher guideline concordance (beta-coefficient, 3.6; 95% CI = 1.5 to 5.7).

Conclusions: Overall ED concordance with guideline-recommended processes of care was low to moderate. Emergency physicians should continue to work with other stakeholders in AMI care, such as emergency medical services (EMS) and cardiologists, to develop strategies to improve care processes.

Figure 1

Patient flow.

Figure 2

Distribution of composite guideline concordance score at the ED level. The scores are normally distributed. The superimposed curve represents the normal curve based on sample mean and SD.