# Mechanical device for the prevention of VTE in high risk patient populations

> **NIH NIH R44** · OSCIFLEX LLC · 2021 · $986,710

## Abstract

Principal Investigator: Welsh, John D
Project Summary
 Deep venous thrombosis (DVT) and secondary pulmonary embolism (PE) affect 0.1-0.2% of the
population and cause approximately 100,000 deaths annually in the US. Immobility and lack of muscular
activity is the primary risk factor for DVT, an effect attributed to reduced venous flow. Autopsy studies
have identified the venous valve sinus in the leg as the site of origin for DVT, but a molecular and cellular
mechanism for this observation has not been identified. Present therapies for DVT include systemic
anticoagulation pneumatic compression devices designed to augment venous flow. Our recent studies
reveal that oscillatory shear forces generated in the venous valve sinus by muscular activity are required
to stimulate a powerful anti-thrombotic endothelial phenotype that prevents venous thrombosis.
Consistent with this mechanism, analysis of venous valves harvested at autopsy from individuals who
died of DVT and fatal PE reveals reversal of the anti-thrombotic phenotype in the peri-valvular
endothelium.
 These studies are the first to identify a hemodynamic, cellular and molecular mechanism for DVT
that explains its tight association with immobility and its site of origin at the venous valve sinus. They
suggests that a mechanical device that restored peri-valvular oscillatory flow in high-risk patients would
effectively prevent DVT by maintaining the natural anti-thrombotic mechanism. Analysis of existing
pneumatic devices reveals that they fail to drive oscillatory flow at the venous valve required to prevent
DVT. Thus, we designed the OsciFlex device that uses a unique actuation technique to create robust
oscillatory flow in the peri-valvular pocket. The goal of this proposal is to extend our initial studies to
develop a finalized device design that is ready for prolonged human use, regulatory approval, and clinical
testing. We will work with clinicians, engineers, and human factors experts to improve the device design
and function and be ready to conduct a decisive clinical trial at the end of the project.

## Key facts

- **NIH application ID:** 10138498
- **Project number:** 2R44HL145860-02
- **Recipient organization:** OSCIFLEX LLC
- **Principal Investigator:** John D Welsh
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $986,710
- **Award type:** 2
- **Project period:** 2019-06-15 → 2022-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10138498

## Citation

> US National Institutes of Health, RePORTER application 10138498, Mechanical device for the prevention of VTE in high risk patient populations (2R44HL145860-02). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10138498. Licensed CC0.

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