Haemocompatibility is an evaluation of the effects of medical devices on blood and the blood components which they come in contact with. It confers to a set of properties that indicate the ability of the material to come in contact with the blood without resulting in adverse reactions. In terms of regulatory requirements, the material is tested in relation to 5 main test categories: Thrombus Coagulation Platelets Haematology Immunology
Problems with haemocompatibility arise due to the foreign body response of the body. Endothelium cells line the walls of blood vessels. When blood comes in contact with a material that is not endothelial it will result in the activation of the blood clotting cascade and the complement system. (Brynda et al., 2000) The activation of the blood clotting cascade (also known as the coagulation cascade) or the complement system can cause major complications following vascular intervention. The activation of these systems can lead to blood clotting and inflammation at the site of the medical device. This can result in occlusion of the vessel, restricting blood flow and causing many complications up to, and including, heart attack, pulmonary embolism, and stroke.
There are many different types of …show more content…
They comprise 2 channels in their shaft: a central lumen through which a movable guide wire may be passed and an outer channel through which the dilation balloon is inflated. This type of catheter is advantageous if the catheter needs to be replaced with a catheter of a different size during the procedure. The guide wire can be left in place, the original catheter removed and the new catheter can then be threaded over the wire. However there can be difficulties in maintaining the position of the guide wire during the catheter exchange process. It often requires the use of a very long exchange wire which can prove difficult to handle. (Jung et al.,