The diagnosis of unstable angina pectoris has declined markedly with the advent of more sensitive troponin assays.
Am J Med. 2015 Mar 26;
Authors: D'Souza M, Sarkisian L, Saaby L, Poulsen TS, Gerke O, Larsen TB, Diederichsen AC, Jangaard N, Diederichsen SZ, Hosbond S, Hove J, Thygesen K, Mickley H
Abstract
BACKGROUND: Since the arrival of the universal definition of myocardial infarction more sensitive troponin assays have been developed. How these occurrences have influenced the proportions and clinical features of the components of acute coronary syndrome have not been prospectively studied in unselected hospital patients.
METHODS: During 2010 we evaluated all patients in whom cardiac troponin I had been measured at one single university hospital. The diagnosis of acute myocardial infarction (ST-elevation myocardial infarction [STEMI] or non-ST elevation myocardial infarction [NSTEMI]) was established in cases of a rise and/or fall of cardiac troponin I together with cardiac ischemic features. Patients with unstable chest discomfort and cardiac troponin I values below the decision limit of myocardial infarction were diagnosed as having unstable angina pectoris. The definition of acute coronary syndrome included unstable angina pectoris, NSTEMI and STEMI. Mortality data were obtained from the Danish Civil Personal Registration System.
RESULTS: Of 3.762 consecutive patients 516 had acute coronary syndrome. Unstable angina pectoris was present in 7%, NSTEMI in 67% and STEMI in 26%. NSTEMI patients were older, more frequently women and had more co-morbidities than patients with unstable angina pectoris and STEMI. At median follow-up of 3.2 years 195 patients had died: 14% of unstable angina pectoris, 45% of NSTEMI and 25% of STEMI patients. Age adjusted log-rank statistics revealed differences in mortality: NSTEMI vs. unstable angina pectoris (p=0.0091) and NSTEMI vs. STEMI (p=0.0045).
CONCLUSIONS: The application of the universal definition together with the employment of a contemporary troponin assay appears to have reduced the proportion of patients with unstable angina pectoris to the benefit of patients with NSTEMI. Despite this NSTEMI patients have a sustained higher mortality than patients with STEMI.
PMID: 25820165 [PubMed - as supplied by publisher]