Objectives: Mortality in cardiogenic shock complicating acute coronary syndrome is high, and objective risk stratification is needed for rational use of advanced therapies such as mechanical circulatory support. Traditionally, clinical variables have been used to judge risk in cardiogenic shock. The aim of this study was to assess the added value of serial measurement of soluble ST2 and amino-terminal pro-B-type natriuretic peptide to clinical parameters for risk stratification in cardiogenic shock.
Design: CardShock (www.clinicaltrials.gov NCT01374867) is a prospective European multinational study of cardiogenic shock. The main study introduced CardShock risk score, which is calculated from seven clinical variables at baseline, and was associated with short-term mortality.
Setting: Nine tertiary care university hospitals.
Patients: Patients with cardiogenic shock caused by acute coronary syndrome (n=145).
Interventions: In this substudy, plasma samples from the study patients were analyzed at eight time points during the ICU or cardiac care unit stay. Additional prognostic value of the biomarkers was assessed with incremental discrimination improvement.
Measurements and main results: The combination of soluble ST2 and amino-terminal pro-B-type natriuretic peptide showed excellent discrimination for 30-day mortality (area under the curve, 0.77 at 12 hr up to 0.93 at 5-10 d after cardiogenic shock onset). At 12 hours, patients with both biomarkers elevated (soluble ST2, ≥ 500 ng/mL and amino-terminal pro-B-type natriuretic peptide, ≥ 4,500 ng/L) had higher 30-day mortality (79%) compared to those with one or neither biomarkers elevated (31% or 10%, respectively; p < 0.001). Combined measurement of soluble ST2 and amino-terminal pro-B-type natriuretic peptide at 12 hours added value to CardShock risk score, correctly reclassifying 11% of patients.
Conclusions: The combination of results for soluble ST2 and amino-terminal pro-B-type natriuretic peptide provides early risk assessment beyond clinical variables in patients with acute coronary syndrome-related cardiogenic shock and may help therapeutic decision making in these patients.