Troponin Levels Diverge Between Type 1 and Type 2 MI, but Mortality Runs in the Opposite Direction
A systematic analysis of eight studies found that cardiac troponin values are consistently higher in type 1 than type 2 myocardial infarction, with weighted differences of 32% for TnT and 91% for TnI regardless of assay sensitivity. Paradoxically, post-discharge mortality was three times higher in type 2 MI patients, highlighting that lower troponin levels in type 2 MI should not reassure clinicians about prognosis. These findings underscore the importance of accurate differential diagnosis and appropriate risk stratification for the distinct pathophysiology of each MI subtype.
The original study
Cardiac troponins and mortality in type 1 and 2 myocardial infarction.
- Authors
- Lippi G, Sanchis-Gomar F, Cervellin G
- Journal
- Clinical chemistry and laboratory medicine
- Type
- Journal Article, Review
- PMID
- 27394046
Original abstract
BACKGROUND: The pathogenesis of different types of myocardial infarction (MI) differs widely, so that accurate and timely differential diagnosis is essential for tailoring treatments according to the underlying causal mechanisms. As the measurement of cardiac troponins is a mainstay for diagnosis and management of MI, we performed a systematic literature analysis of published works which concomitantly measured cardiac troponins in type 1 and 2 MI. METHODS: The electronic search was conducted in Medline, Scopus and Web of Science using the keywords "myocardial infarction" AND "type(-)2" OR "type II" AND "troponin" in "Title/Abstract/Keywords", with no language restriction and date limited from 2007 to the present. RESULTS: Overall, 103 documents were identified, but 95 were excluded as precise comparison of troponin values in patients with type 1 and 2 MI was unavailable. Therefore, eight studies were finally selected for our analysis. Two studies used high-sensitivity (HS) immunoassays for measuring cardiac troponin T (HS-TnT), one used a HS immunoassay for measuring cardiac troponin I (HS-TnI), whereas the remaining used conventional methods for measuring TnI. In all studies, regardless of type and assay sensitivity, troponin values were higher in type 1 than in type 2 MI. The weighted percentage difference between type 1 and 2 MI was 32% for TnT and 91% for TnI, respectively. Post-discharge mortality obtained from pooling individual data was instead three times higher in type 2 than in type 1 MI. CONCLUSIONS: The results of our analysis suggest that the value of cardiac troponins is consistently higher in type 1 than in type 2 MI.