Management And Outcomes Of Acute Coronary Syndrome With Minimal Myocardial Necrosis: Analysis Of A Large Prospective Registry From A Non-Interventional Centre

The aim of this study was to assess the clinical risk of minimal myonecrosis below the cut-off for acute myocardial infarction (MI) in comparison with other grades of acute coronary syndrome (ACS).One-thousand four hundred and sixty seven consecutive patients with ACS admitted between May 2001 and April 2002 were studied in a non-interventional centre. Patients were divided into unstable angina (UA) (cTnT < 0.01 mu g/l), non-ST elevation ACS with minimal myonecrosis (0.01 <= cTnT < 0.1 mu g/l), non-ST elevation MI (NSTEMI) (cTnT >= 0.1 mu g/L) and ST elevation myocardial infarction (STEMI). UA (n = 638) was associated with the fewest events at 6 months (2% cardiac death or MI). Patients with any myonecrosis (n = 829) had worse outcomes (6-month cardiac death or MI 18.3-23.3%). Compared with ACS patients with minimal myonecrosis, UA patients were at significantly lower risk (OR 0.21, 95% Cl 0.12-0.45, p < 0.001), NSTEMI patients were at similar risk (OR 1.45, 95% Cl 0.89-2-35, p = 0.13), and NSTEMI patients were at higher risk (OR 2.12 95% Cl 1.26-3.85, p = 0.008) in adjusted analyses. Nearly 85% of cardiac deaths occurred within 6 months. The risk of adverse events was higher among patients managed by non-cardiologists (OR 1.66, 95% Cl 1-2.75, p = 0.049).Patients with non-ST elevation ACS and minimal myonecrosis are a high-risk group more comparable with NSTEMI and clearly distinguishable from patients with UA.