Disorders of microcirculation in the lungs according to perfusion spect data in patients in post COVID-19 condition

Abstract

Сonsidering the influence of the SARS-CoV-2 virus on the pulmonary vascular system, manifested by the development of endotheliitis, vasculitis, thrombosis and coagulopathies, one of the leading directions of radiological examination may be the study of microcirculation by SPECT. Purpose. To assess changes in the microvasculature of the lungs of patients who have undergone COVID infection at different times from the onset of the disease. Material and methods. SPECT data were analyzed in 170 patients with previous coronavirus infection from May 2020 to June 2021 of varying severity. The results of SPECT, MSCT, FVD and coagulation hemostasis (D-dimer, fibrinogen) were compared. Results. All patients were found to have changes in microcirculation in the lungs in the postcoid period. The severity of microcirculation disorders had a significant dependence (p <0.05, r = 0.76) on the degree of damage to the pulmonary parenchyma and an average correlation dependence (r = 0.51) on the timing of the postcoid period. Signs of PE / microthrombosis changes were significantly more frequent (p <0.05, r = 0.82) in patients with a more severe course of the disease. In patients with CLD, microcirculation decreased to critical levels, the overall level of decrease was up to 30% or more compared to the dock period (p = 0.034). The detection of small subsegmental level of triangular microcirculation defects, with partially restored blood flow, correlated to a high degree (r = 0.84) with an increase in the level of fibrinogen (4.6 + 1.8 mg / l) and indicated the consequences of PE, and an increase in the level of D-dimer (1750+ 215 ng / ml) with the presence of a triangular shape of defects in the accumulation of radiopharmaceuticals correlated to a high degree (r = 0.88) with PE. Conclusion. Disorders of microcirculation in the lungs persist for a long time. They are detected in patients, regardless of the severity of the course of the pathological process, they increase during a dynamic study in patients, the deficit of perfusion depends on the degree of damage to the pulmonary parenchyma. The SARS-CoV-2 virus has a detrimental effect on the state of blood circulation in patients with chronic lung diseases. In patients who have undergone COVID-19 with the development of thrombosis, signs of postponed pulmonary embolism are revealed and zones of local pneumosclerosis are formed.