Monitoring quality of care in acute myocardial infarction patients using retrospective registry data

Background: Hospital-based registries provide a key contribution in assessing the quality of care in acute myocardial infarction (MI) patients, although some concern on selection bias of included cases has recently arisen. We investigated the feasibility of a retrospective, population-based registry of MIs in monitoring the quality of care. Methods: We identified all the hospitalizations with a diagnosis of acute MI among 35-79 years old residents in the Varese province, Northern Italy, in 2007-2008. Information needed to define performance according to the American Heart Association set was extracted from hospital case histories. To characterize our approach, we focus on data completeness for critical event times and eligibility criteria, and on the analysis of ST-elevated MI (STEMI) patients according to received reperfusion treatment. Results: Exact time of hospital admission and of percutaneous coronary angioplasty (PCI) procedure was available in 96% and 77% of MIs, with no difference between non-transferred (n = 1399) and inter-hospital transferred (n = 300) patients. Data completeness for eligibility to action/treatment criteria was >90% for each performance measure except statin prescription at discharge (76%). About 45% of STEMI experienced a delay in PCI-capable hospital arrival, and only one every three ST-elevated MI patients received primary PCI; these were more likely to be younger male cases with less comorbidities than un-treated patients. Conclusions: Complementary to clinical registries, the retrospective population-based is a feasible approach which allows monitoring the entire pattern of care of all hospitalized MI patients independent of their clinical characteristics.