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COVID-19 has proven to be particularly challenging given the complex pathogenesis of SARS-CoV-2. Early data have demonstrated how the host response to this novel coronavirus leads to the proliferation of pro-inflammatory cytokines, massive endothelial damage, and generalized vascular manifestations. While SARS-CoV-2 primarily targets the upper and lower respiratory tract, other organ systems are also affected. SARS-CoV-2 relies on 2 host cell receptors for successful attachment: angiotensin-converting enzyme 2 and transmembrane protease serine 2. Clinicopathologic reports have demonstrated associations between severe COVID-19 and viral coagulopathy, resulting in pulmonary embolism; venous, arterial, and microvascular thrombosis; lung endothelial injury; and associated thrombotic complications leading to acute respiratory distress syndrome. Viral coagulopathy is not novel given similar observations with SARS classic, including the consumption of platelets, generation of thrombin, and increased fibrin degradation product exhibiting overt disseminated intravascular coagulation-like syndrome. The specific mechanism(s) behind the thrombotic complications in COVID-19 patients has yet to be fully understood. Parenteral anticoagulants, such as heparin and low-molecular-weights heparins, are widely used in the management of COVID-19 patients. Beyond the primary (anticoagulant) effects of these agents, they may exhibit antiviral, anti-inflammatory, and cytoprotective effects. Direct oral anticoagulants and antiplatelet agents are also useful in the management of these patients. Tissue plasminogen activator and other fibrinolytic modalities may also be helpful in the overall management. Catheter-directed thrombolysis can be used in patients developing pulmonary embolism. Further investigations are required to understand the molecular and cellular mechanisms involved in the pathogenesis of COVID-19-associated thrombotic complications.

The aim was to evaluate the right ventricular function in patients with inherited thrombophilia and deep vein thrombosis (DVT) without pulmonary embolism. A total of 38 patients with DVT without symptomatic pulmonary embolism and 30 patients with varicose veins were enrolled. Clinical data, echocardiography, and 2 thrombophilic mutations were analyzed. Factor V Leiden (FVL) polymorphism was significantly frequent in the study group (P = .007). The difference in prothrombin G20210A polymorphism between the study and control groups was at a near-significant level (P = .058). There was statistically significant decrease in tricuspid annular plane systolic excursion values in patients with FVL and prothrombin G20210A polymorphism. Combined FVL and prothrombin G20210A polymorphisms were more closely related to the decrease in this value (P = .006). Deep vein thrombosis had no additional adverse effects on right ventricle. Impaired right ventricular systolic function occurs in FVL and prothrombin G20210A polymorphisms.

This study aimed to investigate the significance of the prethrombotic state (PTS) and 4 plasma markers in predicting perisurgical adverse cardiac events in patients with coronary heart disease (CHD) undergoing abdominal surgery. Perioperative adverse effects were recorded in 128 consecutive patients with CHD undergoing elective abdominal surgery. Plasma d-dimer, P-selectin, von Willebrand factor (VWF), and thrombus precursor protein were measured before and after the surgery. Patients with abnormal values in one or more of the 4 PTS markers were identified as having PTS, and data were analyzed by univariate and multivariate logistic regression. Abnormal presurgery levels of the 4 markers were found more frequently in those with adverse perioperative cardiac events than in those without. Multivariate analysis showed the odds ratios for adverse cardiac events to be 64.3 (PTS, P < .001), 25.7 (VWF, P = .003), and 23.5 (P-selectin, P = .04). Preoperative PTS is an independent risk factor for perioperative events in patients with CHD undergoing noncardiac surgery.

Objectives: To compare the effects of the beta-blocker atenolol with the angiotensin receptor blocker (ARB) losartan on plasma tissue-type plasminogen activator (tPA) activity and mass concentration, plasminogen activator inhibitor-1 (PAI-1) activity, tPA/PAI-1 complex, and von Willebrand factor (VWF)., Design: A prespecified, explorative substudy in 22 patients with hypertension and left ventricular hypertrophy (LVH) performed within randomized multicenter, double-blind prospective study., Results: After a median of 36 weeks of treatment, there were significant differences between the treatment groups, atenolol versus losartan, in plasma median levels of tPA mass (11.9 vs 7.3 ng/mL, P = .019), PAI-1 activity (20.7 vs 4.8 IU/mL, P = .030), and tPA/PAI-1 complex (7.1 vs 2.5 ng/mL, P = .015). In patients treated with atenolol, median levels of tPA mass (8.9-11.9 ng/mL, P = .021) and VWF (113.5%-134.3%, P = .021) increased significantly, indicating a change toward a more prothrombotic state. No significant changes occurred in the losartan group., Conclusion: Losartan treatment was associated with preserved fibrinolytic balance compared to a more prothrombotic fibrinolytic and hemostatic state in the atenolol group. These findings suggest different fibrinolytic and hemostatic responses to treatment in hypertensive patients with LVH.

The existence of an association between idiopathic intracranial hypertension (IIH) and coagulation disorders in men was assessed prospectively. Microthrombi, associated with thrombophilia-hypofibrinolysis, occlude arachnoid sinus villi, thus reducing resorption of cerebrospinal fluid, leading to IIH. Ten consecutively referred men with IIH, nine whites, one African American, median age 36 years, were 2 to 1 matched by age and race by healthy male controls. Polymerase chain reaction assays were done for four thrombophilic and one hypofibrinolytic gene mutations: G1691A factor V Leiden, G20210A prothrombin, C677T MTHFR, platelet glycoprotein IIb/IIIa (PL A1/A2), and 4G/5G polymorphism of the plasminogen activator inhibitor (PAI-1) gene promoter. Coagulation measures in plasma included dilute Russel's viper venom time (dRVVT), activated partial thromboplastin time (aPTT), the lupus anticoagulant, factor VIII, factor XI, plasminogen activator inhibitor activity (PAI-Fx), protein C antigenic, protein S total (antigenic), protein S free (antigenic), antithrombin III (functional), and resistance to activated protein C (RAPC). Tests performed on serum included anticardiolipin antibodies, homocysteine, and Lp(a). The body mass index was 40 kg/m(2) or greater (extremely obese) in two men, 30 to 40 kg/m(2) (obese) in three, and was 25 to 30 kg/m(2) in five (overweight). Cases differed from controls for inherited 4G4G homozygosity of the PAI-1 gene, four of 10 (40%) vs. one of 20 (5%), Fisher's p [p(f)]= .031, and for high levels (>21.1 U/mL) of the hypofibrinolytic PAI-1 gene product, PAI-Fx, 5 of 10 (50%) vs. one of 18 (6%), p(f) = .013. Thrombophilic factor VIII was high (> or = 150%) in three of 10 (30%) cases vs. zero of 16 (0%) controls, p(f)=. 046. The thrombophilic lupus anticoagulant was present in two of 10 (20%) cases vs. zero of 32 (0%) controls, p(f) = .052. Heritable hypofibrinolysis and heritable and acquired thrombophilia appear, speculatively, to be treatable etiologies of IIH in men. Understanding contributions of hypofibrinolysis and thrombophilia to the development of IIH should facilitate development of novel new approaches to treat this often-disabling neurologic disorder.