2012 – 2015 Post-Doc Research Fellowship
Thiel Embalmed Human Cadaveric Alternatives to Animal Models for Cardiovascular Device Testing and Training
Professor John Graeme Houston
It has been recently recognised that an alternative embalming process developed by Walter Thiel provides an improved model for testing and training which is becoming more widely recognised.
Our early work in the cardiovascular field has shown that it is a realistic solution for cardiovascular device testing and training. This project is focussed on the development, testing and training of cardiovascular device implantation to treat arteries and veins.
There is an opportunity to replace the established animal testing in this field with a newly adopted embalmed cadaveric model using human bodies donated to medical science. In particular this model will be evaluated as a means of testing three main types of common cardiovascular device: endovascular stents, inferior vena caval filters and aortic stent grafts.
Endovascular stents and aortic stent grafts are metal stiffeners or scaffolds that are inserted inside arteries. They are widely used to treat narrowed or dilated arteries in the heart and other arteries supplying the brain, kidneys, and legs. However the stents can often fail due to narrowing within the stent or blood clotting of the stent. Therefore new types of stent and stent graft are currently being developed for clinical use.
Currently the testing of the stent design, the delivery and implantation of arterial stents and stent grafts rely on animal experimentation. An inferior vena caval (IVC) filter, an umbrella-like device that stops blood clots from the legs travelling to the lungs, avoiding life threatening pulmonary embolus, and aortic aneurysm stent grafts, intra-arterial devices to avoid the rupture of aortic aneurysms, offer less invasive alternatives to complex surgery for these life-threatening conditions. Currently the testing of the design, the delivery and implantation of IVC filters and aortic stent-grafts rely on extensive animal experimentation.
These animal experiments range from rabbits to pigs, sheep and dogs, and nearly always involve animal sacrifice as part of the testing required for regulatory approval (USA Food and Drug Administration - FDA and European Certificate - CE mark approval). Our recent work using a different type of embalming process has demonstrated that the arteries and veins are open.
The Thiel cadavers offer the alternative to animal testing in the preliminary phases of development, testing and training. In particular the testing of stents, IVC filters and aortic stent-graft delivery, anatomical appropriateness and flow testing can be undertaken, thereby avoiding use of animals at this stage by using a limited number of human cadavers donated for medical research. The longer term aim would be to replace animal testing for that stage of regulatory approval and for cardiovascular device implantation clinical training, however it is recognised this will take some time as animal trials are the established regulatory model.