Antithrombotic therapy in ventricular assist device (VAD) management: From ancient beliefs to updated evidence. A narrative review

Abstract

Platelets play a key role in the pathogenesis of ventricular assist device (VAD) thrombosis; therefore, antiplatelet drugs are essential, both in the acute phase and in the long-term follow-up in VAD management. Aspirin is the most used agent and still remains the first-choice drug for lifelong administration after VAD implantation. Anticoagulant drugs are usually recommended, but with a wide range of efficacy targets. Dual antiplatelet therapy, targeting more than one pathway of platelet activation, has been used for patients developing a thrombotic event, despite an increased risk of bleeding complications. Although different strategies have been attempted, bleeding and thrombotic events remain frequent and there are no uniform strategies adopted for pharmacological management in the short and mid- or long-term follow up. The aim of this article is to provide an overview of the evidence from randomized clinical trials and observational studies with a focus on the pathophysiologic mechanisms underlying bleeding and thrombosis in VAD patients and the best antithrombotic regimens available.

Acute ischemic stroke management in a patient with ventricular assist device

“…For these patients blood pressure regulation is a must! INR should be evaluated more commonly, and for those who had thrombus complications before, INR should be between 3-3.5 considering the risk of hemorrhage [1][2][3][4][5][6][7][8][9][10][11][12][13].…”

Evaluation of aspirin platelet inhibition in left ventricular assist device population

“…Heat stress is an additional mechanism by which thromboembolic complications have discovered decreased clotting time, increased clotting strength, and increased thrombin and D-dimer release. 22 Thrombus formation leading to pump thrombosis can result in patients requiring pump exchange, stroke, and death. 16 Pump thrombosis increases morbidity and mortality, with a median time to development of 18.9 months postimplant; leading to pump replacement or cardiac transplantation.…”

“…Although stress stimulation on vWF aggregation is affected very little from the presence of cyclo‐oxygenase inhibition by acetylsalicylic acid, the importance of aspirin resistance relies with the idea of heat stress. Heat stress is an additional mechanism by which thromboembolic complications have discovered decreased clotting time, increased clotting strength, and increased thrombin and D‐dimer release 22 …”

Acquired von Willebrand Syndrome and Platelet Function Defects during Extracorporeal Life Support (Mechanical Circulatory Support)

“…Aspirin is frequently used as therapy in VAD patients, but causes an ongoing matter of debate since shearinduced platelet aggregation seems to be unaffected by aspirin. 47 For both ECMO and VAD patients, the best therapeutic option to prevent bleeding as well as thrombosis is rigorous weaning from the device as soon as possible.…”