Platelet Count and Bleeding in Patients Receiving Anticoagulant Therapy for Venous Thromboembolism: Lesson from the RIETE Registry

Diagnosis and treatment of deep vein thrombosis of the lower and upper limbs. 2024 recommendations of the venous thromboembolism group of the Spanish Society of Internal Medicine

Deep vein thrombosis (DVT) of the limbs is a common disease and causes significant morbidity and mortality. It is frequently the prelude to pulmonary embolism (PE), it can recur in 30% of patients and in 25-40% of cases they can develop post-thrombotic syndrome (PTS), with a significant impact in functional status and quality of life. This document contains the recommendations on the diagnosis and treatment of acute DVT from the Thromboembolic Disease group of the Spanish Society of Internal Medicine (SEMI). PE and thrombosis of unusual venous territories (cerebral, renal, mesenteric, superficial, etc.) are outside its scope, as well as thrombosis associated with catheter and thrombosis associated with cancer, which due to their peculiarities will be the subject of other positioning documents of the Thromboembolic Disease group of the Spanish Society of Internal Medicine (SEMI).

Anticoagulation With Platelet Transfusions for Acute Limb Ischemia With Severe Thrombocytopenia

Acute limb ischemia (ALI) is a medical and surgical emergency, and the mainstays of treatment are therapeutic anticoagulation and surgery. These interventions require adequate platelet count and functionality. Anticoagulation and surgery can be complicated in thrombocytopenic patients and require interdisciplinary management for optimal outcomes, as literature is limited in this population. We present a case of a patient with severe thrombocytopenia who developed limb ischemia from cancer-associated thrombosis (CAT). We propose a management strategy for anticoagulation and perioperative platelet transfusion, with successful revascularization without adverse bleeding events. While successful, more data is required to investigate long-term outcomes.

Effectiveness and Safety of Apixaban vs Warfarin in Patients with Venous Thromboembolism with Risk Factors for Bleeding or for Recurrences

INTRODUCTION

Patients at increased risk of bleeding and recurrent VTE who develop venous thromboembolism (VTE) present challenges for clinical management. This study evaluated the effectiveness and safety of apixaban vs warfarin in patients with VTE who have risk factors for bleeding or recurrences.

METHODS

Adult patients with VTE initiating apixaban or warfarin were identified from five claims databases. Stabilized inverse probability treatment weighting (IPTW) was used to balance characteristics between cohorts for the main analysis. Subgroup interaction analyses were conducted to evaluate treatment effects among patients with and without each of the conditions that increased the risk of bleeding (thrombocytopenia and history of bleed) or recurrent VTE (thrombophilia, chronic liver disease, and immune-mediated disorders).

RESULTS

A total of 94,333 warfarin and 60,786 apixaban patients with VTE met selection criteria. After IPTW, all patient characteristics were balanced between cohorts. Apixaban (vs warfarin) patients were at lower risk of recurrent VTE (HR [95% confidence interval (CI) 0.72 [0.67-0.78]), major bleeding (MB) (HR [95% CI] 0.70 [0.64-0.76]), and clinically relevant non-major (CRNM) bleeding (HR [95% CI] 0.83 [0.80-0.86]). Subgroup analyses showed generally consistent findings with the overall analysis. For most subgroup analyses, there were no significant interactions between treatment and subgroup strata on VTE, MB and CRNM bleeding.

CONCLUSION

Patients with prescription fills for apixaban had lower risk of recurrent VTE, MB, and CRNM bleeding compared with warfarin patients. Treatment effects of apixaban vs warfarin were generally consistent across subgroups of patients at increased risk of bleeding/recurrences.

Endothelial Activation and Immune Thrombocytopenia: An Engagement Waiting for Consolidation

Immune thrombocytopenia (ITP) appears to be a heterogeneous disease. In some patients, autoimmunity may be associated with an inflammatory process, and in other patients, low platelets may interfere with other aspects of the coagulation system. Either may predispose to thrombosis or bleeding. Further investigation of the interactions of platelets, with inflammatory cytokines and endothelial biomarkers, may help us to better understand the disease, and to recognize those patients at risk of bleeding, or conversely thrombosis. The aim of this work is to estimate von Willebrand factor (vWF) and vascular cellular adhesion molecule (V-CAM) serum levels in adult immune thrombocytopenic patients (ITP) and to decipher their possible clinical correlates. Eighty adults (≥ 18 years) were enrolled in the study; naive newly diagnosed 40 patients with primary ITP (according to the ASH 2019) and 40 sex and age-matched healthy controls, all groups are subjected for complete blood count (CBC), liver, and renal function tests, ESR, CRP, V-CAM, and VWF-Ag by enzyme-linked immunosorbent assay (ELISA). There was a highly statistically significant difference between case and control as regards to the mean level of VWF-Ag and V-CAM. vWF and V-CAM could serve as biomarkers for endothelial alterations and should be investigated as a predictor of thrombocytopenic bleeding and tailor patient management accordingly.