Prognostic significance of indicators of the dynamics of troponin i concentration after off-pump coronary bypass grafting and hybrid myocardial revascularization

Objective. To assess the prognostic significance of dynamic indicators of troponin I concentration after off-pump coronary artery bypass grafting (CABG) and hybrid myocardial revascularization (HMR) and identification of factors influencing the development of postoperative complications.
Methods. The prospective single-center randomized comparative study included 180 patients with multifocal coronary artery disease. Group 1 (n = 98) consisted of patients who underwent off-pump CABG. Group 2 (n = 82) included patients who underwent hybrid myocardial revascularization. HMR consisted of two stages. The 1st stage was minimally invasive direct mammary coronary bypass grafting with access through a left minithoracotomy. The 2nd stage, 1–3 days after the open surgery, was percutaneous coronary intervention using drug-eluting stents.
Results. The highest concentrations of Tn and AUCTn after CABG are characteristic of patients with a peak content of the cardiac marker in the bloodstream 24 hours after surgery, which indicates a longer and more intense release of it into the bloodstream after surgery.
Prognostically unfavorable for patients who have undergone CABG is an increase in the concentration of Tn by 12 hours after surgery (Tn12in/Tnin) by 68 times or more. Patients with Tn12/Tnin ≥ 68 have a sharply reduced event-free survival within 12 months after CABG (p = 0.001). Patients with a combination of Tn12/Tnin ≥ 68 and a late peak Tn concentration are at high risk of adverse clinical outcomes after CABG.
A high level of Tn by 24 hours after breast cancer is associated with impaired carbohydrate metabolism: the presence of type 2 diabetes (rpb = 0.41), BMI (rpb = 0.33), preoperative concentrations of glucose (rpb = 0.35) and glycated hemoglobin (rpb = 0.41). Prognostic criteria for a Tn concentration of more than 0.2 ng/ml by 24 hours after breast cancer are the presence of CKD and the number of stented arteries in patients with elevated levels of glycated hemoglobin.
Conclusion. With unidirectional changes in the concentration of highly-sensitive Tn I after CABG and HMR, a less pronounced release of the cardiomarker into the bloodstream in patients after HMR indicates less myocardial trauma during hybrid myocardial revascularization.

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