Abstract: TH-PO769
Platelet Accumulated Stress Modeling Predicts Platelet Activation and Thrombosis
Session Information
- Bioengineering
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bioengineering
- 300 Bioengineering
Authors
- Marsh, Emily, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Groszek, Joseph J., STERIS, Lakewood, Ohio, United States
- Williams, Phillip E., Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Laneve, David C., Vanderbilt Medical Center, Brentwood, Tennessee, United States
- Goodin, Mark S., SimuTech Group, Hudson, Ohio, United States
- Goebel, Steven G., SimuTech Group, Hudson, Ohio, United States
- Buck, Amanda, Vanderbilt University, Nashville, Tennessee, United States
- Wright, Nathan, UCSF, San Francisco, California, United States
- Bluestein, Danny, Stony Brook University, Stony Brook, New York, United States
- Forbes, Rachel C., Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Roy, Shuvo, UCSF, San Francisco, California, United States
- Fissell, William Henry, Vanderbilt University, Nashville, Tennessee, United States
Background
Thrombosis is a dreaded complication in blood-contacting medical devices including implantable artificial kidneys (IAK). Fluid shear stress primes platelets to initiate thrombosis. We compared computational predictions of platelet accumulated stress (PAS), biochemichemical assays of platelet activation, and in vivo thrombosis between two different implanted hemofilter designs.
Methods
Platelet accumulated stress distributions under unsteady flow in two candidate blood conduit designs were predicted using computational fluid dynamics (CFD) tools. Hemofilter catrtridges were machined from polycarbonate and implanted in Class A dogs for 2-7 days without anticoagulation. Platelet activation was measured using a modified prothrombinase assay. Thrombosis was assessed by measuring cyclic variation in blood velocity downstream of a controlled femoral artery lesion.
Results
The two different hemofilter designs gave rise to two distinct histograms of PAS. In some animals, the hemofilter with the larger PAS (A) thombosed almost immediately while the other hemofilter (B) did not. In animals where both cartridges remained patent, platelet stress as measured by prothrombinase activity agreed with CFD predictions. Femoral artery flow was disrupted to a greater extent in animals implanted with hemofilter A than Hemofilter B.
Conclusion
We showed that CFD predicted biochemical measures of platelet activation and propensity to thrombosis in an animal model of an implanted hemofilter. Platelet stress is a useful tool to predict thromboembolic complications in blood contacting medical devices.
Pulsatile flow was comapred between a femoral artery with a standarized trauma (red) and a contralateral control artery (green). Cyclic variations in flow distinct from respiration arise from transient thrombosis at the arterial trauma.
Funding
- Other NIH Support