Implantable left ventricular assist device (LVAD) therapy is used to improve quality of life, alleviate symptoms and extend survival rates in patients with advanced heart failure. Patients with LVADs require chronic anticoagulation to reduce the risk of thromboembolic complications, and they commonly experience bleeding events.
The Problem
LVAD patients require life-long anticoagulant therapy to reduce the risk of pump thrombosis. Anticoagulation management in patients with LVADs continues to be a challenge. Patients and their clinicians are faced with the daily challenge of needing adequate anticoagulation versus the bleeding risks that are associated with anticoagulation. Warfarin is the recommended oral anticoagulant for all currently available LVAD devices. Warfarin is known to be a difficult medication to manage due to its narrow therapeutic window, and its many interactions.
There is a need for randomized controlled trials in LVAD patients to determine the optimal antithrombotic regimen and find the most effective balance between thrombotic and bleeding complications.
LVAD SYSTEM
FIGURE 1 illustrates the left ventricular assist device (LVAD) blood pump components which include the inflow cannula, a lower housing, a screw ring to attach the pump cover to the lower housing, a motor, the outflow graft, and a pump cable.
FIGURE 2 illustrates the LVAD system comprising the Driveline, composed of a pump cable that extends from the LVAD through the skin, and the modular cable which connects the pump cable to the system controller. The driveline powers the pump motor and facilitates communication with the system controller.
THE PREVALENCE
The INTERMACS report provides number of implanted devices by year from 2010 to 2019 as well as the survival time. The chart below provides a summary of the expected number of subjects surviving in 2019. The total number of subjects surviving in 2019 from implantations beginning in 2010 is approximately 14,419.
PREVALENCE
The INTERMACS report provides number of implanted devices by year from 2010 to 2019 as well as the survival time. The total number of subjects surviving in 2019 from implantations beginning in 2010 is approximately 14,419.
Our Solution
Anticoagulation via vitamin K antagonism is the only currently proven means of effectively reducing thrombosis / thromboembolisms of LVAD origin.
The evidence generated on tecarfarin metabolism suggests that it may provide a lower risk option by virtue of its different metabolism via the high expression and high capacity hCE2 instead of the cytochrome P450 pathways utilized by warfarin.
Given the high prevalence of renal insufficiency in the LVAD population a comparison of the PK of warfarin vs tecarfarin in normal vs renal insufficiency patients is informative and suggests that tecarfarin may represent a safer alternative for vitamin K antagonism in LVAD patients.
