Factors determining the effectiveness of various antithrombotic therapy regimens after coronary artery bypass surgery in patients with diffuse lesions and small diameter of coronary arteries: a 12-month prospective follow-up

Objective. To evaluate the factors determining prognosis within a year after coronary artery bypass grafting (CABG) in patients with diffuse lesions and/or small (<1.5mm) diameter of target arteries, as well as the effect of antithrombotic therapy (ATT) on clinical outcomes and graft occlusion. Material and methods. A single-center open prospective study included patients who underwent CABG with diffuse lesions and/or small (<1.5 mm) diameter of at least one coronary artery. This study was intended to compare different ATT regimens. Depending on therapy, patients were divided into 3 groups: ASA, ASA+C, ASA+R. Clinical outcomes were thrombotic complications in any vascular bed, recurrent angina and/or need for repeat percutaneous coronary intervention, major bleeding (BARC 2—5). Loss of bypass grafts was assessed according to CT angiography. Results. The final analysis included 201 patients. The median prospective follow-up was 12 months. There was 1 thrombotic complication (non-fatal myocardial infarction) and 3 cases of bleeding. None event led to fatal outcomes. Compared with ASA alone, any variant of multicomponent ATT was associated with lower incidence of angina recurrence and/or need for PCI (37.3 vs. 20.3%, p=0.010). The highest effects of multicomponent therapy were observed in patients without «target» LDL-C values. The incidence of angina recurrence and/or need for PCI in the ASA and ASA+C groups was 41.1 vs. 12.1% (OR=0.291), respectively, incidence of occlusion of at least one graft — 68.4% and 39.3% (OR=0.657). The incidence of occlusions of small-diameter venous grafts was significantly higher in the aspirin group compared to any variant of enhanced therapy (53.5 vs. 22.5%, p=0.0007). Conclusion. «Enhanced» ATT significantly reduces the risks of recurrent angina and/or the need for PCI, as well as the incidence of graft occlusion in patients without «target» LDL-C. «Enhanced» therapy has a protective effect on venous grafts to small (<1.5 mm) arteries.