“HyperShear in a channel”: A microfluidic facsimile of ventricular assist devices to reduce thrombotic risk and enhance patient safety

Thrombosis of ventricular assist devices is a significant complication compromising device efficacy with attendant risks of systemic embolization, stroke, pump stop and death. Presently anti-thrombotic therapy is utilized to mitigate thrombotic risk. Drugs such as aspirin and dipyridamole are largely dosed empirically, without individualized testing of efficacy in a given patient. To date testing systems available for examining anti-platelet agent efficacy are limited in that they are largely central lab-based and typically examine drug efficacy under conditions that do not represent the flow and shear conditions of the patient during actual VAD use. In the present paper we adopt a technology, Device Thrombogenicity Emulation - a methodology developed by our group which characterizes the actual shear stress history experienced by platelets in a blood recirculating device, i.e. total exposure level, individual platelet flight trajectories - and utilize this to create a facsimile of the shear stress profile of a ventricular assist device in a small footprint microfluidic channel point-of-care system. Creating a device-specific microfluidic facsimile will allow the development of a point-of-care testing system reflective of an actual device in a given patient. This will afford determination of anti-thrombotic agent efficacy under personalized conditions, reducing the likelihood of VAD thrombosis, increasing overall patient safety.