ST2 and mortality in non-ST-segment elevation acute coronary syndrome.

BACKGROUND: ST2 is a member of the interleukin-1 receptor family that is up-regulated in conditions associated with increased myocardial strain. ST2 has been shown to be independently predictive of adverse outcome in heart failure and ST-segment elevation myocardial infarction, but its prognostic value in non-ST-elevation acute coronary syndrome (NSTE-ACS) has not been established. METHODS: We measured ST2 at randomization and after 24, 48, and 72 hours in 403 NSTE-ACS patients from the GUSTO IV study, and studied its kinetics and its associations to clinical baseline factors and 1-year mortality. RESULTS: Median ST2 levels decreased from 28.4 U/mL at randomization to 21.8 U/mL at 72 hours (P < .001). Peak levels were noted 6 to 17 hours after symptom onset. Randomization ST2 levels were independently associated to N-terminal pro-B-type natriuretic peptide but otherwise exhibited only weak relations to cardiovascular risk factors and comorbidities, and biomarkers of myocardial necrosis or inflammation. ST2 was related to 1-year mortality independently of clinical risk indicators (odds ratio 2.3 [95% CI 1.1-4.6], P = .03) but lost its predictive value after additional adjustment for prognostic biomarkers, in particular N-terminal pro-B-type natriuretic peptide. CONCLUSIONS: ST2 levels are elevated early in NSTE-ACS and predict 1-year mortality. Our data indicate that ST2 represents an interesting novel pathophysiologic pathway in the setting of ischemia-related myocardial dysfunction. However, future prospective evaluations in larger populations are needed before the clinical utility of ST2 can be determined.

Duke Scholars

Author Paul Wayne Armstrong Medicine, Cardiology

Author Robert M. Califf Medicine, Cardiology