Abstract 802: Biomarker Elevations Late After Myocardial Infarction and Association With Health Status
Introduction: While one clinical trial suggested that detectable troponin (TnT) and elevated N-terminal pro-B-type Natriuretic Peptide (NTBNP) at 1 to 6 months after discharge for a myocardial infarction (MI) are associated with worse survival, little is known about the prevalence of elevations in a ‘real world’ MI population or the association with patient-centered outcomes such as health status.
Methods: We assessed TnT and NTBNP levels in a substudy of TRIUMPH, a prospective MI registry from 24 US hospitals. Subjects who had 1 month (N=1296) or 6 month (N=832) post discharge biomarkers were included. Health status was assessed using the Seattle Angina Questionnaire, a 4-point dyspnea scale, and the Short Form-12 (SF12). The association of angina, dyspnea, and physical function with detectable TnT (>0.01 ng/ml) and elevated NTBNP (>400 pg/ml) was tested using hierarchical models adjusted for site. Covariates were age, gender, race, left ventricular function class, MDRD glomerular filtration rate, MI type (ST elevation vs. not), and severity of coronary disease.
Results: At 1 and 6 months, 14% and 9% of patients had detectable TnT, while 55% and 33% had elevated NTBNP, respectively. In adjusted models, 1 and 6 month detectable TnT and elevated NTBNP were associated with worse dyspnea and physical function (Figure⇓). Elevated 6 month NTBNP, but not TnT, was also associated with angina.
Conclusions: In a diverse MI population, elevated TnT and NTBNP 1 to 6 months post discharge are common and associated with worse health status. Further study is needed to understand if this signifies ongoing pathologic processes in such patients and define the utility of biomarker monitoring after MI.