The coronary blood flow plays an important role in protecting the myocardium from ischemia and maintaining the cardiomyocyte function in the event of occlusion of one of the epicardial arteries. It also has a potential for restoring the contractile function during subsequent myocardial revascularization, which requires its more detailed research. Most methods for assessing coronary collaterals are carried out to define the potential of their use for Retrograde chronic total occlusion recanalization. Currently, the most widely used method for assessing collateral blood flow is angiography, which, despite its relative simplicity and good knowledge, has following limitations: invasiveness, operator dependence, limited visualization, etc. At the same time, a number of other diagnostic methods can also be used to assess collateral flow. This review article is aimed at a detailed study of modern invasive and non-invasive methods for assessing the development and function of collateral vessels.

Background: Bifurcation treatments make up ca. 15–20% of coronary interventions. Despite the use of drug-eluting stents, the management of bifurcation lesions, especially with side branches involved, remains a challenge.Objective: To evaluate long-term clinical and angiographic outcomes after using a paclitaxel-coated balloon for the treatment of side branches in patients with true bifurcation lesions.Methods: Eighty patients with coronary artery disease were enrolled after true bifurcation lesion stenting. All patients were randomized at the 1:1 ratio to the group of main branches stenting followed by the dilatation of side branches with drug-eluting balloons and provisional stenting group.Results: Long-term results were analyzed after 12 months. The most common bifurcation lesion involved the left anterior descending artery and diagonal branch (57.5%). Late lumen loss in the side branch (0.51 ± 0.22 vs 0.33 ± 0.24 mm) and in both the bifurcation branches (main branch + side branch) (1.06 ± 0.29 vs 0.79 ± 0.27 mm) was significantly higher in the patients after provisional stenting.Overall postoperative incidence of major adverse cardiovascular events was 17.5% and 7.5% (p = 0.31) in the provisional stenting and drug coated balloon groups, respectively. Patients with drug-eluting balloons for the treatment of side branches had a more pronounced decrease in angina symptoms after 12 months. Multivariate analysis showed that diabetes mellitus (OR: 10.9) and glomerular filtration rate (OR: 0.95) were independent predictors of major adverse cardiovascular events in bifurcation interventions.Conclusion: Drug-eluting balloons for the dilatation of side branches after the stenting of main branches are superior to provisional stenting in terms of the late lumen loss. Received 31 August 2022. Revised 17 November 2022. Accepted 18 November 2022. Funding: The study did not have sponsorship. Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: T.K. Eraliev, D.A. Khelimskii, A.G. Badoian, O.V. KrestyaninovData collection and analysis: T.K. Eraliev, D.A. Khelimskii, A.G. Badoian, O.V. Krestyaninov, A.A. Baranov, A.P. GorgulkoStatistical analysis: T.K. Eraliev, D.A. Khelimskii, A.G. BadoianDrafting the article: T.K. Eraliev, D.A. Khelimskii, A.G. Badoian, O.V. Krestyaninov, A.A. Baranov, A.P. GorgulkoCritical revision of the article: T.K. Eraliev, D.A. Khelimskii, A.G. Badoian, O.V. KrestyaninovFinal approval of the version to be published: T.K. Eraliev, D.A. Khelimskii, A.G. Badoian, O.V. Krestyaninov, A.A. Baranov, A.P. Gorgulko

Despite the technological developments in the healthcare industry, cardiovascular disease mortality occupies a leading place among the structure of general mortality of the population. The use of modern treatment methods, especially, percutaneous coronary intervention, provides timely assistance to patients with acute coronary syndrome and helps to reduce mortality frequency. Currently, clear algorithms for the management of patients with ST-segment elevation myocardial infarction have been developed. However, despite it, there are paradigms in the management of patients with non-ST-segment elevation myocardial infarction (NSTEMI). This is primarily due to the fact that the vast majority of patients with NSTEMI are elderly and senile persons. This review article presented the main factors that adversely affect short- and long-term prognosis and results of clinical studies dedicated to the study of this problem.

Transcatheter aortic valve replacement is an appropriate alternative to open surgery in some patients with severe aortic stenosis who have significant comorbidities and high surgical risk.Aim. To evaluate the immediate results of transcatheter aortic valve replacement in patients with severe aortic stenosis.Material and Methods. This is a retrospective study, which included 350 patients who underwent transcatheter aortic valve replacement from 2015 to 2021. Mortality, complications, clinical data, and echocardiographic parameters were assessed in the early postoperative period after the procedure.Results. The patient mean age was 75.3 ± 7.2 years. The majority of patients had intermediate surgical risk: EuroScore II of 6.7 ± 5.4 and STS-PROM score of 3.3 ± 1.9. In most cases, there was severe hypertrophy of left ventricular (LV) myocardium with an average LV myocardial mass of 330.9 ± 88.4 g. The average postprocedural pressure gradient across the aortic valve was 8.9 ± 4.4 mm Hg. The most common procedural complication was complete heart block (10%). In-hospital mortality rate was 1.7%.Conclusion. Our register demonstrated the optimal immediate clinical and echocardiographic results of transcatheter aortic valve replacement in patients with severe aortic stenosis.