The prognostic utility of troponin T levels in patients undergoing PCI during initial hospitalisation for STEMI

Abstract The prognostic utility of presentation or "peak" high-sensitivity troponin T (hsTnT) levels following ST-segment elevation myocardial infarction (STEMI) has been previously reported, but hsTnT, unlike other bio-markers of myocyte damage, have a 2nd or ‘plateau-phase’ of release which lasts over a week. We have reported correlations between plateau-phase hsTnT levels, and cardiac MRI determined infarct size, though whether these levels are more highly associated with late mortality than "peak" (or highest) levels, needs clarification. Methods Hence we determined late mortality and the combination of cardiovascular death, myocardial infarction and cerebrovascular accident [CD/MI/CVA] among patients with STEMI, and an HsTnT level >36 hours after symptom onset (plateau phase), who underwent percutaneous coronary intervention (PCI), either primary or pharmaco-invasive, during initial hospitalisation between October 2003 and December 2021. HsTnT levels and other potential prognostic factors were determined. Results Amongst 1955 patients, 119 patients (6%) had died by 2 years and 192 (10%) patients experienced CD/MI/Stroke. The highest quartile of plateau phase hsTnT levels (³ 3786 ng/L ng/L), were more highly associated with 2-year mortality, than the highest quartile of "peak" hsTnT levels (³ 7687 ng/L ng/L). The Figure shows Peak and plateau hs-TnT levels in quartile groups were assessed by rank test to obtain p-values. Patients lost to follow-up or with less than 2-years of follow up were considered censored. Peak quartile 1; hs-TnT £ 1611 ng/L, peak quartile 2; hs-TnT 1612 – 3900 ng/L, peak quartile 3; hs-TnT 3901 – 7686 ng/L; peak quartile 4; hs-TnT ³ 7687 ng/L. Plateau quartile 1; hs-TnT £ 1060 ng/L, plateau quartile 2; hs-TnT 1061 – 2135 ng/L; plateau quartile 3; hs-cTnT 2136 – 3785 ng/L. Log rank mortality analyses are shown in the Figure. Peak quartile 1; hs-TnT <1611 ng/L, peak quartile 2; hs-TnT 1612 – 3900 ng/L, peak quartile 3; hs-TnT 3901 – 7686 ng/L; peak quartile 4; hs-TnT ³ 7687 ng/L. Plateau quartile 1; hs-TnT £ 1060 ng/L, plateau quartile 2; hs-TnT 1061 – 2135 ng/L; plateau quartile 3; hs-cTnT 2136 – 3785 ng/L, plateau quartile 4; hs-TnT >3786 ng/L. Multivariate Cox regression analysis incorporating age, sex, smoking status, hypertension, renal function, cardiogenic shock and heart failure hospitalisation found plateau hs-TnT levels (HR, 3.564; 95% CI, 1.674 – 7.590; P = 0.001) were an independent predictor of all-cause mortality at 2-years post-STEMI, whereas peak hs-cTnT levels (HR, 1.965; 95% CI, 0.959 – 4.025; P = 0.065) were not. Conclusions Plateau phase hsTnT levels were of prognostic significance in STEMI patients treated with PCI. Thus, measurement of plateau hs-cTnT levels following STEMI could be an accurate, inexpensive method of long-term prognostic risk stratification.