ABSTRACT
Violations of the hemostasis (blood aggregation control, BAC) system in patients with COVID-19 in the acute period and at the stage of convalescence have been studied and methods of targeted correction of the identified disorders are considered. Prevention of serious complications related to COVID-19 infection requires complex assessment of the hemostasis system and prompt correction of disorders. Methods of clinical hemostasiograms and low-frequency piezothromboelastography (LPTEG) provide comprehensive and informative assessment of functional state of the BAC system and monitoring of the effectiveness of therapy, both in hospital and on outpatient basis. It was established that hemostasis system disorders had unspecified character with hyper- or hypocoagulation in the acute period and structural or chronometric hypercoagulation in the recovery period. Under LPTEG monitoring in hospital, the identified disorders were corrected by low-molecular-weight (LMW) heparins, blood-based preparations, and fibrinolysis inhibitors;at the outpatient stage, the therapy was supplemented with sulodexide and anticoagulants. Personalized correction of the hemostatic potential was based on the following LPTEG parameters. Prescription of the anti-aggregant and vasoprotective therapy required that the response time (t1) would be reduced below 0.9 min and thrombin activity (TA) constant increased above 40 relative units. The anticoagulant therapy was prescribed when the gelation point (t3) decreased to 4.7 min and the coagulation drive intensity (CDI) index was above 50 relative units. The fibrinolytic activity was corrected when the clot polymerization intensity (CPI) index was above 20 relative units, the cross-linked fibrin formation time (t5) decreased to 27 min, and the clot retraction and lysis intensity (CRLI) index exceeded 15%. The boundary values of these LPTEG parameters were adjusted at the levels of moderate hypercoagulation or reference normal coagulation. The LPTEG monitoring and personalization of the prescribed antithrombotic therapy allowed the risk of thrombo-hemorrhagic complications to be reduced at all stages of COVID-19 treatment.Copyright © 2021 Authors. All rights reserved.
ABSTRACT
BACKGROUND: Deep vein thrombosis (DVT) is commonly identified and diagnosed in the emergency department. Factors including sedentary life (immobility), pregnancy in women, cancer, postoperation, admission to ICU, smoking, and obesity are identified risks for thrombosis development. We report a case of a 35-year-old man who presented to the emergency department developing left lower leg swelling and pain, low-grade fever, and headache after he was treated and discharged, cured of severe COVID-19. Then venous and arterial Doppler ultrasound of the lower leg revealed dilated, absent flow and luminal thrombus in the distal popliteal, anterior and posterior tibial veins and perforator vessels were diagnosed as leg DVT. CONCLUSION: DVT is a hematological emergency that needs serious consideration in prevention as well early diagnosis in patients with possible risk factors. This case report aims to arouse the clinician's awareness of the occurrence of deep vein thrombosis during and after COVID-19.
ABSTRACT
Many populations suffer from thrombotic disorders such as stroke, myocardial infarction, unstable angina and thromboembolic disease. Thrombus is one of the major threatening factors to human health and the prevalence of cardio-cerebrovascular diseases induced by thrombus is growing worldwide, even some persons got rare and severe blood clots after receiving the AstraZeneca COVID vaccine unexpectedly. In terms of mechanism of thrombosis, antithrombotic drugs have been divided into three categories including anticoagulants, platelet inhibitors and fibrinolytics. Nowadays, a large number of new compounds possessing antithrombotic activities are emerging in an effort to remove the inevitable drawbacks of previously approved drugs such as the high risk of bleeding, a slow onset of action and a narrow therapeutic window. In this review, we describe the causes and mechanisms of thrombus formation firstly, and then summarize these reported active compounds as potential antithrombotic candidates based on their respective mechanism, hoping to promote the development of more effective bioactive molecules for treating thrombotic disorders.