PANDORA`S BOX OR «NO-REFLOW» PHENOMENON (CLINICAL CASE)
Authors: Denina R. V. , Seredyuk N. M. , Matlakh A. Ya. , Didenko O. S. , Korolyuk V. D. , Hnatyk M. Ya. 
Published: April 2022

It has been established that successful repefusion of ocluded infarct-dependent coronary artery (IDCA) during percutaneous coronary intervention does not mean restoration of myocardial perfusion. This «no-reflow» phenomenon is known from the studies of R. Kloner, C. Ganote, R. Jennings (1974). They were among the first to note only a partial restoration of coronary blood flow after the reperfusion of mechanically occluded for 90-180 minutes coronary artery in dogs. The authors considered damage to the capillary endothelium, edema of the damaged wall and extravasal tissues, and protrusion into the capillary cavity to be the cause of this phenomenon.
The frequency of the phenomenon of «no-reflow» after the successful restoration of coronary blood flow in the IDCA varies between 5 - 40% of all cases. The development of this phenomenon was an unfavorable prognostic factor, primarily in terms of mortality and deterioration of the functional state of the left ventricle.
The pathophysiology of the «no-reflow» phenomenon remains poorly understood. Obviously, it has a multifactorial nature and cannot be described by any one mechanism.
Analyzing the phenomenon of «no-reflow», it is noted that in spite of the reperfusion of IDCA, there are pronounced pathophysiological changes in the microcirculatory tract, the essence of which is to block myocardial perfusion in the area of myocardial infarction.
During the COVID-19 pandemic, the number of patients with myocardial infarction increased, including an increase in the number of diagnosed «no-reflow» and «slow-flow» phenomena, which is associated with the impact of SARS СOVID-19 virus on the myocardium, namely the development of microvascular damage.
There is currently no specific therapy for the prevention and treatment of «no-reflow» phenomen that would be recommended for patients with STEMI.
This article presents a clinical case of the phenomenon of «no-reflow» in patient B., 56 years old, who complained of severe chest pain, irradiation in the left shoulder and lower jaw, shortness of breath, general weakness. History of hypertension, coronavirus PCR +. Troponin I - 5.4 ng/ml. According to the electrocardiogram: elevation of the ST segment in II. III, aVF leads. At the time of contrast infusion during stenting of infarct-dependent right coronary artery, its slow filling was recorded - the phenomenon of «no-reflow» TIMI 0, MBG-0. The patient was discharged from the hospital in satisfactory condition under the supervision of a family doctor.
Conclusions:

The phenomenon of «no-reflow» is a topical and unresolved issue of myocardial revascularization in real clinical practice.
The most common prerequisite for the development of the phenomenon of «no-reflow» after myocardial revascularization is late hospitalization, and aggravating circumstances - comorbid pathology (COVID-19, hypertension, diabetes).
This clinical case is interesting because the patient with lesions of the lower left ventricular wall PCI was complicated by the phenomenon of «no-reflow», as evidenced by the slowing of ST segment resolution, lack of myocardial perfusion, parietal thrombosis throughout the RCA.
Further search for ways to prevent and treat irreversible blood flow syndrome after successful reperfusion of infarct-dependent coronary artery is needed.