High-sensitivity cardiac troponin I after coronary artery bypass grafting for post-operative decision-making

Abstract

Aims Current troponin cut-offs suggested for the post-operative workup of patients following coronary artery bypass graft (CABG) surgery are based on studies using non-high-sensitive troponin assays or are arbitrarily chosen. We aimed to identify an optimal cut-off and timing for a proprietary high-sensitivity cardiac troponin I (hs-cTnI) assay to facilitate post-operative clinical decision-making. Methods and results We performed a retrospective analysis of all patients undergoing elective isolated CABG at our centre between January 2013 and May 2019. Of 4684 consecutive patients, 161 patients (3.48%) underwent invasive coronary angiography after surgery, of whom 86 patients (53.4%) underwent repeat revascularization. We found an optimal cut-off value for peak hs-cTnI of >13 000 ng/L [>500× the upper reference limit (URL)] to be significantly associated with repeat revascularization within 48 h after surgery, which was internally validated through random repeated sampling with 1000 iterations. The same 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 validated in an external cohort. A decision tree analysis of serial hs-cTnI measurements showed no added benefit of hs-cTnI measurements in patients with electrocardiographic or echocardiographic abnormalities or haemodynamic instability. Likewise, early post-operative hs-cTnI elevations had a low yield for clinical decision-making and only later elevations (at 12–16 h post-operatively) using a threshold of 8000 ng/L (307× URL) were significantly associated with repeat revascularization with an area under the curve of 0.92 (95% confidence interval 0.88–0.95). Conclusion Our data suggest that for hs-cTnI, higher cut-offs than currently recommended should be used in the post-operative management of patients following CABG. Key question To describe the kinetics of high-sensitivity cardiac troponin I (hs-cTnI) after elective coronary artery bypass graft (CABG) surgery and assess which hs-cTnI cut-offs correlate with clinically meaningful findings. Key finding High-sensitivity cardiac troponin I levels determined 12–16 h after surgery with a cut-off of 8000 ng/L (307× upper reference limit) correlated best with a decision to repeat revascularization, while at earlier time-points, clinical decision should rather be based on electrocardiogram (ECG), echocardiographic, and haemodynamic criteria. Take-home message High-sensitivity cardiac troponin I aids decision-making when determined 12 h or later after CABG utilizing higher cut-offs than currently recommended, at earlier time-points workup should be based on ECG, echo, and haemodynamic criteria.

Comparison of Bretschneider HTK and Blood Cardioplegia (4:1): A Prospective Randomized Study

“…Similarly, in our study, only the level of CK-MB from CS after cross-clamping was significantly lower in the IBC compared with the HTK group while no difference was seen with cTnI in comparison. For that reason, as the sensitivity and specificity of cTn are superior to CK-MB, 16 this finding could not be enough to talk about the superiority of one solution over another in our opinion.…”

Right coronary artery deformation and injury following tricuspid valve surgery

“…Our data showed that outcome in patients who required post-operative coronary angiography after tricuspid surgery was significantly worse. Post-operative coronary angiography is mostly performed due to hemodynamic instability, post-operative ST-segment elevation, significantly elevated levels of cardiac markers or due to ventricular wall motion disorders in echocardiography indicating myocardial ischemia ( 10 ). In some patients, in particular in patients with concomitant left-sided valve procedure, coronary interventions on the left coronary artery were necessary.…”

Cardiac troponin release following coronary artery bypass grafting: mechanisms and clinical implications

“…Although the requirement for supporting findings is a widely debated topic, and recent pivotal studies have refuted an association of isolated peak biomarker release-based definitions and impaired prognosis, 12,16 the need for supporting ECG and imaging evidence is beyond the scope of the current review.…”

“…15 Biomarker measurements are the cornerstone of the diagnosis of PMI, but supporting evidence might be crucial. 12,16 These supporting findings comprise either ECG or imaging findings. Especially in studies evaluating postoperative cTn values with delayed enhancement cardiac magnetic resonance (DE-CMR) follow up, the amount of myocardial injury identified by DE-CMR was correlated with peak cTn and predictive of adverse prognosis.…”

“…14,123 Furthermore, irrespective of the use of cTnI or cTnT, supporting evidence in terms of ECG or imaging findings seems to be of utmost importance, while there is little diagnostic value of isolated biomarker increases in the acute phase. 2,12,16,104 The terms reversible and irreversible myocardial injury require clarification, while they are being used in different settings with different meanings. [124][125][126] In an interesting opinion paper on primary MI patients, Jaffe and Wu 124 rightfully stated that even if cTn release is in part the consequence of reversible injury, clinically one does not need to make a differentiation between reversible and irreversible injury in non-surgical patients, as they both prove to influence prognosis.…”