Abstract 2251: Introduction of Troponin Increased the Number of Patients with a Discharge Diagnosis of Myocardial Infarction but did not Change Overall Mortality: a Twelve-year Experience from a Tertiary Care Center.
Background: Acute myocardial infarction (AMI) continues to be a common cause of mortality in the United States. With the introduction of more accurate biomarkers and changes in the criteria for AMI diagnosis, the epidemiology of AMI has changed over time. It is however unclear if the wide-spread adoption of troponin assays for AMI diagnosis has changed its incidence and mortality over time.
Methods: We identified all the patients between 1992 and 2003 who were discharged from Henry Ford Hospital with a primary diagnosis of AMI. Patients with AMI as a secondary or complicating diagnosis were excluded. Mortality data was extracted using the hospital database and the Michigan death registry. One year mortality rates were compared against the introduction of different generations of troponin I assays in the hospital laboratory.
Results: 8527 patients had primary discharge diagnosis of AMI. There was a progressive increase in the number of patients discharged with MI diagnosis over time (515 in1992 to 940 patients in 2003). The biomarker used to diagnose AMI in 1992 was creatinine kinase MB fraction. The first, second and third generation troponin I measurements were introduced in the hospital in 1994, 1998, and 2002 respectively. There were no significant changes in one-year mortality before and after introduction of different troponin I assays (p value 0.68. Figure⇓).
Conclusion: Discharge diagnosis of AMI progressively increased in a single tertiary care hospital with introduction of troponin I assay. Although, the more sensitive assays can potentially detect smaller MIs, there was no significant decline in the one-year mortality of MI patients.