Aim. To evaluate the changes of cell-free DNA (cfDNA) levels before and after percutaneous coronary intervention (PCI) in patients with ST-segment elevation acute coronary syndrome (STE-ACS). To identify associations of cfDNA concentration before and after PCI with complications and length of ulcerated plaque in patients with STE-ACS.Material and methods. This prospective single-center observational pilot study included 44 patients with STE-ACS admitted to the cardiac intensive care unit during the period of May-August 2023. In all patients, along with standard laboratory tests, cfDNA level was measured upon admission and 24 hours after PCI. Assessment of cfDNA associations before and after PCI was carried out in relation to following significant complications and conditions in STE-ACS patients: death, acute left ventricular failure (ALVF), acute heart failure (AHF), arrhythmia, number of stents implanted, number of segments with impaired local contractility, total stent length.Results. The mean age of the patients was 60,6±9,6 years, of which 74,6% were men. TIMI 0-1 flow was recorded in 93,2% of the subjects. The most common complications were cardiogenic shock (18,4%), arrhythmia (16,9%), AHF (13,6%), ALV (11,9%). Death was recorded in 8,5%. Implantation of 1 stent in PCI was performed in 75% of cases, while in the rest, 2 or more stents were implanted. The proportion of patients with impaired local contractility was 90%, the median stent length was 24,0 (20,0-50,0) mm. CfDNA level on admission did not differ from level after PCI 94,5 (78,3-155,5) ng/ml vs 115,0 (71,0-152,0), p=0,46. However, it signi­ficantly exceeded the cfDNA concentration from a group of healthy volunteers (78,0 (59,7-106,0), p=0,017). Characteristic curve showed significant relationships both for the concentration of cfDNA before (with implantation of 2 or more stents (AUC 0,71 with 95% confidence interval (CI) 0,56-0,86, p=0,039), stent length >24 mm (AUC 0,73 with 95% CI 0,58-0,89, p=0,009)) and after PCI (with the number of impaired local contractility segments (AUC 0,73 with 95% CI 0,57-0,89, p=0,014)). If the cfDNA level before PCI was >90 ng/ml, the risk of implantation of 2 or more stents per procedure increased by 5,4 times (odds ratio (OR) 5,4, 95% CI 1,11-28,93, p=0,044). The risk of a stent length >24 mm with pre-PCI cfDNA >107 ng/ml increased 9-fold (OR 9,0 with 95% CI 2,2-36,9, p=0,001), and the cfDNA level after PCI >105 ng/ml increased the risk of impaired local left ventricular (LV) contractility in 2 or more segments by 5 times (OR 5,0, 95% CI 1,23-20,3).Conclusion. In the studied group of patients with STE-ACS subject to intervention, the cfDNA concentration before PCI was associated with the implantation of ≥2 stents and the stent length (>24 mm). CfDNA level before PCI was associated with the number of segments of impaired local LV contractility (≥2).

Atrial fibrillation (AF) and heart failure (HF) often accompany each other, as they share similar risk factors and pathophysiological mechanisms. AF in patients with HF is known to increase hospitalizations and worsen prognosis. A combination of AF and HF translates into high risks of thromboembolic complications, which renders anticoagulants an important aspect of therapy for these patients. Vitamin K antagonists make achieving the target level of anticoagulation challenging due to drug interactions and comorbidities. Direct oral anticoagulants (DOACs) are preferred medications owing to a more favorable risk-benefit ratio in this group of patients. At the same time, patients with HF often require a personalized approach when choosing an anticoagulant due to increased risks of thromboembolic complications and bleeding, as well as multiple comorbidities. The article presents the results of sub-analyses of key studies on the efficacy and safety of DOACs vs vitamin K antagonists in patients with HF and AF. It also explores DOACs use in patients with chronic kidney disease.