VASCULAR_GRAFTS_Biomedical Engineering.pptx

Vascular Grafts

1. VASCULAR GRAFTS

2. Vascular grafts are artificial blood vessels used to replace or repair damaged blood vessels in the body. They are commonly used in surgeries such as coronary artery bypass grafting, peripheral artery bypass, and hemodialysis access. Conduits used to replace the diseased or blocked blood vessels are called vascular grafts It can either be arteries, veins or capillaries. Introduction

3. Tissue engineering involves growing cells on a scaffold to create a functional tissue or organ. - In vascular grafts, cells are grown on a scaffold made from biodegradable materials such as collagen or polycaprolactone . - The cells can be derived from the patient's own body (autologous) or from a donor (allogeneic). Tissue Engineered vascular grafts

4. Autografts: Blood vessels taken from the patient's own body (usually from a vein in the leg) and used to replace damaged vessels. Allografts: Blood vessels taken from a donor (usually a cadaver) and used to replace damaged vessels. Xenografts: Blood vessels taken from another species (such as pigs) and used to replace damaged vessels Synthetic grafts: Graft can be synthetic . Common materials used are ceramic or polymer-based materials Types of vascular grafts

5. Ensuring the graft is strong enough to withstand the pressure of blood flow. - Preventing clotting or blockage at the site of the graft. - Ensuring the cells on the graft integrate with the patient's own cells. - Overcoming regulatory hurdles to bring tissue-engineered vascular grafts to market Challenges in tissue engineered VG

6. Based on size, classified as large calibre , medium calibre and small calibre . Large Calibre : grafts with diameter greater than 8mm. Resistance to blood flow is low in large diameter hence the occurrence to thrombosis is low Medium calibre : diameter is 6-8mm but greater than 5mm Small calibre Diameter lower than 5mm Classification

7. Natural grafts : Usually autologous grafts such as sephonous vein from the leg, internal mammary artery and radial artery from the armare most preferred during vascular surgery These grafts posses physiological properties akin to the native vessel and are considered as gold standard. Synthetic grafts : are being employed as grafts during vascular surgery. Polymers such as expanded TEFLON( ePTFE ) polyethlene terephthalate, Dacron (PET) Based on origin

8. Biocompatible Non thrombogenic Durable Non toxic Must not cause undesirable effects Dimensions and mechanical properties must be similar to natural materials Resistance to infections Characteristics of Vascular grafts

9. Tissue regeneration: Vascular grafts can be used to regenerate damaged tissues by providing a scaffold for new tissue growth. The grafts can be seeded with cells and growth factors to promote tissue regeneration . Organ transplantation: Vascular grafts can be used in organ transplantation to connect the transplanted organ to the recipient's blood supply. This is particularly important in cases where the recipient's own blood vessels are damaged or diseased . Wound healing: Vascular grafts can be used in wound healing to promote the growth of new blood vessels and improve circulation to the affected area . Drug delivery: Vascular grafts can be used as a platform for drug delivery, allowing drugs to be delivered directly to the site of injury or disease . Research : Vascular grafts are also widely used in research as a model system for studying vascular biology and disease. Application