New quality indicator for treatment of acute myocardial infarction

Introduction: Crude mortality is commonly used as a quality indicator (QI) for the treatment of acute myocardial infarction (AMI), but has important limitations including its dependence on the local case-mix. We aimed to explore the feasibility of a novel approach using risk adjustment according to the Global Registry of Acute Coronary Events (GRACE). Methods: In 1471 consecutive patients admitted with AMI to a Swiss university hospital in 2012 and 2013, we quantified working hours needed by a trained healthcare professional to complement the available administrative dataset by detailed medical review of all available medical records to: 1) differentiate the subtypes of AMI in order to separate type 1 (including type 4) AMIs from type 2 and postoperative AMIs (GRACE is only validated for type 1 AMI); 2) add all medical variables required to calculate the GRACE score. Results: Detailed medical review identified 93 additional patients (6.7%) with AMI as the main diagnosis, who were missed in the administrative dataset. Complete data for the calculation of the GRACE score could be obtained for 1233 patients (93.8%). In both years, observed crude mortality was significantly lower than the expected in-hospital mortality using the GRACE model (2012 [n = 613]: crude mortality 6.0%, mean GRACE mortality 8.3% [95% CI 7.2-9.4%]; 2013 [n = 620]: crude mortality 5.8%, mean GRACE mortality 9.4% [95%CI 8.3-10.6%]). Overall, the number of working hours required to retrospectively complement the administrative dataset was 1150 hours (575 h per year). Conclusion: Assessment of risk-adjusted in-hospital mortality in AMI is feasible, provides important insights regarding treatment results while improving comparability between hospitals, but is very time-consuming if done retrospectively. Prospective documentation of the GRACE score within the electronic medical records would help to reduce the effort needed to obtain this novel QI. Further multicentre studies are warranted.