Key result
Post-CABG troponin above 180xULN is linked to ~660% higher 30-day mortality.
Why the study?
The study evaluated the incidence and prognostic significance of post-CABG myocardial infarction using various biomarker-based definitions and sought to identify the peak cardiac troponin threshold independently associated with a 2-fold increase in 30-day mortality.
Do different definitions of post-CABG myocardial infarction alter its reported incidence and prognostic significance for 30-day mortality?
Do different definitions of post-CABG myocardial infarction alter its reported incidence and prognostic significance for 30-day mortality?
The incidence and prognostic significance of post-CABG myocardial infarction vary significantly depending on the biomarker definition used, highlighting the need for validated diagnostic criteria.
Post-CABG troponin thresholds for MI warrant clinical caution; challenges consensus on definitions and leaves open prospective validation.
OBJECTIVES Using data from the CORONARY trial (n = 4752), we evaluated the incidence and prognostic significance of myocardial infarction (MI) applying different definitions based on peak postoperative creatine kinase-MB isoenzyme and cardiac troponin levels. We then aimed to identify the peak cardiac troponin during the first 3 postoperative days that was independently associated with a 2-fold increase in 30-day mortality. METHODS To combine different assays, we analysed cardiac troponins in multiples of their respective upper limit of normal (ULN). We identified the lowest threshold with a hazard ratio (HR) >2 for 30-day mortality independent of EuroSCORE and on- versus off-pump surgery. RESULTS Depending on the definition used based on creatine kinase-MB, the incidence of MI after coronary artery bypass grafting (CABG) ranged from 0.6% to 19% and the associated HRs for 30-day mortality ranged from 2.7 to 6.9. Using cardiac troponin (1528 patients), the incidence of MI ranged from 1.7% to 13% depending on the definition used with HRs for 30-day mortality ranging from 5.1 to 7.2. The first cardiac troponin threshold we evaluated, 180xULN, was associated with an adjusted HR for 30-day mortality of 7.6 [95% confidence interval (CI) 3.4–17.1] when compared to <130xULN. The next independent threshold was 130xULN with an adjusted HR for 30-day mortality of 7.8 (95% CI 2.3–26.1). The next cardiac troponin tested threshold (70xULN) did not meet criteria for significance. CONCLUSIONS Our results illustrate that the incidence and prognosis of a post-CABG MI varies based on the definition used. Validated post-CABG MI diagnostic criteria formulated from their independent association with important clinical outcomes are needed.
No takes yet. Share an insight, caveat, or question.
Belley‐Côté et al. (2019) studied this question. A cardiac troponin threshold of 180xULN was associated with a 7.6 HR for 30-day mortality post-CABG, illustrating significant variability in MI incidence and prognosis.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: