Introduction. Preterm birth disrupts important processes of fetal growth and development and can serve as a trigger for maladaptive organ remodeling in the postnatal ontogenesis. The aim of the study was to evaluate the effect of preterm birth on the angiogenesis of the left ventricular myocardium of rats from days 1 to 21 of the postnatal ontogenesis. Materials and methods. We performed immunohistochemical (CD31) and morphometric (specific volume of blood capillaries, specific volume of cardiomyocytes, diameter of blood capillaries, trophic index and pericapillary diffusion zone) study of the left ventricular myocardium of full-term and prematurely born (12 and 24 hours preterm) Wistar rats (n=88) of both sexes on days 1, 7, 14, and 21 of the postnatal ontogenesis. Results. The birth of rats 12 and 24 hours preterm does not result in change in the specific volume of blood capillaries and the trophic index in the left ventricular myocardium on days 1, 7, 14, and 21 of the postnatal period. Preterm birth leads to a decrease in the specific volume of cardiomyocytes of the left ventricular myocardium of rats, compared to the parameters of animals in the control group, on days 7–21 of the postnatal period. Preterm birth results in a decrease in the diameter of the blood capillaries of the left ventricular myocardium in female rats on day 21 of the postnatal period. Preterm birth (24 hours preterm) is accompanied by an increase in the size of the zone of pericapillary diffusion in the left ventricular myocardium of rats on day 14 of the postnatal ontogenesis, in comparison with that of animals in the control group. Conclusion. The shorter the duration of the intrauterine period of development of rats, the greater the severity of the observed changes in the left ventricular myocardium are. It seems promising to study the functional state of endotheliocytes of myocardial blood vessels in preterm animals in the postnatal period. Keywords: preterm birth, prematurity, myocardium, angiogenesis, vascular indexes

Background/Objectives: Coronary computed tomography angiography (CCTA) is a modern method for assessing the total burden of atherosclerotic lesions. The perivascular fat attenuation index (PFAI) is a reliable predictor of major adverse cardiovascular events (MACE). Radiomics extracts substantially more information from images than visual assessment by radiologists. However, the relationships between quantitative parameters of coronary atherosclerosis, the PFAI, and radiomic features of pericoronary adipose tissue (PCAT) in patients with coronary artery disease (CAD) remain unclear. The study aimed to evaluate the associations between PCAT characteristics, including radiomic features, and quantitative parameters of coronary atherosclerosis in stable CAD patients. Methods: The study included 79 patients with stable CAD who underwent CCTA. The patients were divided into two groups: nonobstructive CAD (NOCAD, stenosis < 50%; n = 61) and obstructive CAD (OCAD, stenosis ≥ 50%; n = 18). The CCTA data were analyzed to quantify coronary atherosclerosis parameters (plaque volume and burden), the PFAI, PCAT volume, and radiomic features of PCAT in the proximal segments of major coronary arteries. Results: The study included 79 patients: NOCAD group = 61 patients (age 57.00 (50.00–65.00) years) and OCAD group = 18 patients (age 60.5 (55.75–65.75) years). The OCAD patients exhibited higher plaque volume and burden across all components. No significant between-group differences were observed in PFAI or PCAT volume for any vessel. However, 50% (46/92) of PCAT radiomic features in the proximal right coronary artery (RCA) differed significantly between groups, 42 of which were textural. The PFAI correlated most strongly with soft tissue (ST) plaque volume (ρ = −0.22), and burden (ρ = −0.21) of the soft tissue component of plaques (p < 0.001). The PCAT volume significantly correlated (p < 0.001) with plaque volume (ρ = 0.30) and with individual components—soft tissue (ρ = 0.30), fibrous–fatty (ρ = 0.27), fibrous (ρ = 0.30), calcified (ρ = 0.22), and non-calcified (ρ = 0.30)—as well as with the burden of the soft tissue component (ρ = 0.26). Conclusions: The radiomic features of RCA PCAT differed significantly between the NOCAD and OCAD groups. Quantitative coronary atherosclerosis parameters showed significant associations with the PCAT radiomic features in CAD patients, potentially serving as independent predictors of the MACE risk. In contrast, the PFAI values did not differ between groups and neither PFAI nor PCAT volume associated with atherosclerosis parameters.

Aim. To evaluate the influence of epicardial adipose tissue (EAT) volume and density, based on computed tomography (CT) data, on the severity of myocardial injury assessed using cardiac biomarkers. Material and methods. The study included patients with newly diagnosed acute myocardial infarction (MI). All patients underwent invasive coronary angiography. Two following groups were formed: 1) MI with obstructive coronary artery disease (MICAD) (stenosis ≥50%); 2) MI with non-obstructive coronary arteries (MINOCA) (stenosis <50%). Cardiac biomarker levels (cardiac troponin I (cTnI), cardiac creatine phosphokinase (CPK-MB)) were determined at admission, 24 hours later, and on days 4 and 7. CT coronary angiography was performed on day 7 hospitalization. EAT volume and density were calculated using CT data. Results . The study included 31 patients as follows: 21 with MICAD (age 62 (56; 68) years) and 10 with MINOCA (age 68 (57; 79) years). MICAD patients had higher levels of cardiac biomarkers. Significant differences in EAT volume were found between MICAD and MINOCA patients (p<0,05). The median EAT volume in MICAD patients was greater than in MINOCA patients: 125 (69,4; 169) cm3 and 70,9 (62,4; 140) cm3, respectively. EAT density did not differ significantly as follows: MICAD -76,3 (-80; -71,6) HU, MINOCA -77,6 (-82,7; -73) HU. In the total sample, a significant nonparametric correlation was found between EAT volume and left ventricular end-diastolic mass (ρ=0,41; p=0,032), body surface area (ρ=0,55; p=0,002), and body mass index (ρ=0,54; p=0,003). EAT density negatively correlated with left ventricular enddiastolic mass (ρ=-0,39; p=0,041), body surface area (ρ=-0,54; p=0,003), and body mass index (ρ=-0,57; p=0,002). In the MINOCA group, negative correlations were obtained between biomarker levels and EAT volume, as well as significant positive correlations between CPK-MB at 24 h and cTnI on the 7th day with EAT density. EAT density was positively associated with elevated cTnI levels on day 7 (odds ratio (OR) 2,0, 95% confidence interval (CI) 1-3,5, p<0,05), CPK-MB at 24 h (OR 1,3, 95% CI 1-2,0, p<0,05), and CK-MB on day 4 (OR 2,0, 95% CI 1-3,5, p<0,05). Conclusion. In the acute period after acute MI, in patients with MINOCA, the EAT phenotype, characterized by a smaller volume and higher density, is associated with greater myocardial damage according to biomarker assessment, while in MICAD, the relationship between EAT properties and cardiac biomarkers is predominantly absent.