ST2 is a strong predictor of cardiovascular death and risk of developing new heart failure in ST Elevation Myocardial Infarction (STEMI) & NSTE-ACS patients. In patients presenting with Acute Coronary Syndrome (ACS), those in the highest quartile (above 35 ng/ml) have more than 3 times higher risk of cardiovascular death and new heart failure at 30 days, than those in the lower quartiles. At one year, there is a relative risk of 2.3 for adverse outcomes.