<International Circulation>: Improvements in heathcare actually leads to the increase in the incidence of some conditions, such as aortic valve calcification. Aortic valve calcification in elderly patients can cause aortic stenosis and because age has increased risk for all kinds of complications and multiple organ dysfunctions, the risk of surgery is very high. Recently, percutaneous aortic valve implantation has presented itself as an appropriate therapy for these special patients. Can you outline the indications and contraindications for the procedure?
<International Circulation>: Percutaneous aortic valve implantation is in its initial stages and not yet perfected. What are the potential problems and solutions arising from this new technology?
Dr Ussia: Currently worldwide, have been treated more than 20000 patients with both of these valves. There is a learning curve which exists for the first twenty to fifty patients so each center conducting the procedure saw a higher rate of complications in the early stages of their experience, but with increased experience, these centers have seen a marked decrease in the complication rates from 10% to 4%. Potential complications are essentially related to the vascular access because we have to use a sheath of large diameter but the companies are markedly reducing the diameter of the equipment and in the future with a 16 French sheath we will dramatically reduce vascular complications. Another specific complication is the potential for AV conduction disturbances with the need for a permanent pace maker, and potential coronary occlusion, but these complications can be reduced with good patient selection and the experience of the operator in correctly positioning the valve.