Introduction of high-sensitivity troponin assays: impact on myocardial infarction incidence and prognosis

Am J Med. 2012 Dec;125(12):1205-1213.e1. doi: 10.1016/j.amjmed.2012.07.015.

Abstract

Objective: The study objective was to compare the incidence and prognosis of acute myocardial infarction when using high-sensitivity cardiac troponin assays instead of a standard cardiac troponin assay for the diagnosis of acute myocardial infarction.

Methods: In a prospective international multicenter study, we enrolled 1124 consecutive patients presenting with suspected acute myocardial infarction. Final diagnoses were adjudicated by 2 independent cardiologists 2 times using all available clinical information: first using standard cardiac troponin levels and second using high-sensitivity cardiac troponin T levels for adjudication. Patients were followed up for a mean of 19±9 months.

Results: The use of high-sensitivity cardiac troponin T instead of standard cardiac troponin resulted in an increase in the incidence of acute myocardial infarction from 18% to 22% (242 vs 198 patients), a relative increase of 22%. Of the 44 additional acute myocardial infarctions, 35 were type 1 acute myocardial infarctions and 9 were type 2 acute myocardial infarctions. This was accompanied by a reciprocal decrease in the incidence of unstable angina (unstable angina, 11% vs 13%). The most pronounced increase was observed in patients adjudicated with cardiac symptoms of origin other than coronary artery disease with cardiomyocyte damage (83 vs 31 patients, relative increase of 268%). Cumulative 30-month mortality rates were 4.8% in patients without acute myocardial infarction, 16.4% in patients with a small acute myocardial infarction detected only by high-sensitivity cardiac troponin T but not standard cardiac troponin, and 23.9% in patients with a moderate/large acute myocardial infarction according to standard cardiac troponin assays and high-sensitivity cardiac troponin T (P<.001).

Conclusions: The introduction of high-sensitivity cardiac troponin assays leads to only a modest increase in the incidence of acute myocardial infarction. The novel sensitive assays identify an additional high-risk group of patients with increased mortality, therefore appropriately classified with acute myocardial infarction (Advantageous Predictors of Acute Coronary Syndromes Evaluation; NCT00470587).

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Aged
  • Biomarkers / blood
  • Coronary Angiography
  • Female
  • Heart Diseases / diagnosis
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Myocardial Infarction / blood*
  • Myocardial Infarction / classification
  • Myocardial Infarction / diagnosis*
  • Myocardial Infarction / mortality
  • Prognosis
  • Prospective Studies
  • Regression Analysis
  • Troponin / blood
  • Troponin T / blood*

Substances

  • Biomarkers
  • Troponin
  • Troponin T

Associated data

  • ClinicalTrials.gov/NCT00470587