Cardiovascular applications heart-assist devices

Other cardiovascular uses have included coatings on pacemakers and pacemaker lead-wires for purposes of insulation and for achieving biocompatibility. Medical grade silicone elastomer has been widely used as a material of construction in experimental artificial hearts and heart assist devices. Silicone tubing is often preferred for use in roller-type blood pumps during cardiopulmonary bypass. Medical grade silicone elastomer contains no leachable or organic plasticizers and thus contributes minimal contamination in blood contact applications. [Pg.90]

Cardiovascular disease, namely, coronary artery disease, remains the leading cause of death in the developed nations. Over the last few years, MEMS sensors have advanced the understanding of blood flow, namely, fluid shear stress, in arterial circulation. Fluid shear stress is defined as the frictional force acting tangentially on the surface of a blood vessel wall. Furthermore, the measurement of wall shear stress is important to study the durability of prosthetic valves and to monitor thrombosis or blood clots in cardiopulmonary bypass machines, artificial hearts, and left ventricular assist devices. Luminal shear stress measurement predicts the development of atherosclerotic plaque in patients at risk for acute heart attacks. In this context, the application of microscale hot-wire anemometry bridges fluid mechanics of blood flow with vascular biology. [Pg.1784]

Biomaterials have played a vital role in the treatment of cardiovascular diseases, examples of applications including heart valve prostheses, vascular grafts, stents, indwelling catheters, ventricular assist devices, total implantable artificial heart, pacemakers, automatic internal cardioverter defibrillator, intraaortic balloon pump, and more. A key requirement for materials in cardiovascular applications, particularly blood-contacting devices, is blood compatibility, that is, nonthrombogenic. Additional requirements include mechanical and surface properties that are application specific. Surveying the field of polymers used in cardiovascular applications reveals that PUs, polyethylene terephthalate (PET), and expanded PTFE (ePTFE) are the most commonly used. This section will review each of the three polymers followed by a brief introduction of other emerging polymers for use in the cardiovascular area. [Pg.151]