Unstable angina in the context of high-sensitive troponins: Still a marker of high risk? A comparison of outcomes with adjudicated type 1 myocardial infarction

Unstable angina (UA), considered historically a marker of high risk, has rarely been studied in the high sensitive troponin era. We sought to characterise this population and determine short- and medium-term outcomes for UA and compared this to both patients with musculoskeletal chest pain and adjudicated type 1 MI (NSTEMI). We conducted a post-hoc analysis of 2 prospective cohort studies of suspected acute coronary syndrome in 2 hospitals in the northwest of England. (n = 3018) We used a dedicated symptom score to diagnose unstable angina. Type 1 MI (NSTEMI) was diagnosed by independent physician adjudication according to 3rd universal definition of MI. Follow-up was 100% complete for all patients to 1 year. 185 (6.1%) and 249 (8.3%) were adjudicated as suffering from UA and NSTEMI respectively. We restricted our analysis of UA to 158 (5.2%) patients with UA with high sensitive troponin T (Roche Elecsys) ≤14 ng/L (≤99th percentile). Compared to the NSTEMI population, the UA cohort were younger (59 vs 74, p 1 mm, 5.1% vs 15.6%, p = 0.001, T wave flattened, biphasic or inverted 24.1% vs 47.8%, p 10-fold lower when compared to NSTEMI, indicating a less severe pathology in terms of atherosclerosis or plaque burden, and implying the need for a different management strategy to that of NSTEMI. •This is the first analysis of UA in the high sensitive troponin era using objective criteria to diagnosis UA.•UA , determined objectively using a symptom score and in the absence of myocyte necrosis, remains prevalent as a diagnosis.•Although subsequent nonfatal M