In vivo detection of hemorrhage rate in dog models of hemophilia and VWD and at human femoral arteriotomy by ARFI ultrasound

There is currently no validated method for assessing hemostasis in vivo. Such a method would facilitate the development of therapeutic clotting factor replacement products for patients with bleeding disorders as well as improve patient care and reduce complications following invasive procedures. We have investigated the use of Acoustic Radiation Force Impulse (ARFI) imaging as a method for assessing bleeding rate in vivo in dog models of inherited bleeding disorders and in human volunteers following arteriotomy for diagnostic percutaneous cardiac catheterization. Our data showed significantly higher bleeding rates in the VWD dogs consistent with the inherited bleeding phenotype. We also saw slower arteriotomy bleeding rates after 5 minutes when a hemostatic dressing is used to augment manual compression. These results suggest that ARFI imaging is relevant to noninvasively monitoring bleeding rates.