The postoperative evaluation of patients following coronary artery bypass graft (CABG) surgery was currently guided by troponin cut-offs derived utilizing non-high-sensitive troponin assays or that were arbitrarily selected. Researchers set out to determine an optimal cut-off and timing for a high-sensitivity cardiac troponin I (hs-cTnI) test, which would aid in post-operative clinical judgment. They conducted a retrospective study to outline all patients who underwent elective isolated CABG at the institution between January 2013 and May 2019. Out of 4,684 patients operated on at the institution, 161 (3.48%) had an invasive coronary angiogram later, of whom 86 (53.4%) had subsequent revascularization. They established a cut-off value of more than 13,000 ng/L [>500× the upper reference limit (URL)] for peak hs-cTnI to be significantly associated with repeat revascularization within 48h after surgery which was corroborated through random repeated sampling with 1,000 iterations. The exact cut-off also predicted 30-day major adverse cardiovascular events and all-cause mortality after a median follow-up of 3.1 years, which was confirmed in external research. Furthermore, hs-cTnI post-operative elevations had a low diagnostic value and only later increases (at 12–16 hours after surgery) using a threshold of 8,000 ng/L (307× URL) were significantly associated with repeat revascularization with an area under the curve of 0.92 (95% CI 0.88-0.95). According to the study, for hs-cTnI, higher cut-offs than the currently recommended should have been used in the postoperative management of individuals who have had CABG.
Link:academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehab918/6528587?searchresult=1
