Association of copeptin with myocardial infarct size and myocardial function after ST segment elevation myocardial infarction.

OBJECTIVE: To investigate the relationship between circulating plasma copeptin values and infarct size as well as myocardial function at baseline and 4 months after mechanical reperfusion for ST segment elevation myocardial infarction (STEMI).
DESIGN: Prospective observational cohort study.
SETTING: University Hospital of Innsbruck. PATIENTS: 54 patients with acute STEMI. MAIN OUTCOME MEASURES: Correlation of plasma copeptin with infarct size as well as left ventricular ejection fraction (LVEF) and remodelling.
METHODS: Participants underwent contrast enhanced cardiac MRI at baseline and 4 months thereafter. Blood samples were drawn 2 days after the onset of symptoms. Copeptin values were determined by an immunofluorescent assay.
RESULTS: Copeptin concentrations (median 10.4 pmol/l, IQR 6.0-14.4) were associated with early and chronic infarct size (r=0.388, p=0.004 at baseline; r=0.385, p=0.011 at follow-up) and inversely related to LVEF at both times (r=-0.484, p<0.001 at baseline; r=-0.461, p<0.001 at follow-up). Patients with adverse remodelling showed higher baseline copeptin values compared to patients without remodelling (p=0.02). Receiver operating characteristic analysis indicated a cut-off value of 16.7 pmol/l for copeptin to best identify patients with future adverse remodelling.
CONCLUSIONS: Increased copeptin values 2 days after STEMI are associated with larger acute and chronic infarct sizes. Moreover, elevated copeptin concentrations at baseline were associated with myocardial function and remodelling 4 months post-STEMI. These findings strengthen the role of copeptin as a biomarker of adverse outcome after STEMI.