[Percutaneous treatment of heart valves].

Percutaneous treatment of heart valves started 2 decades ago in patients with mitral stenosis. In such patients, a stable increase in the mitral valve area could be achieved with balloon dilatation. Complications were infrequent and the outcomes comparable to those obtained with surgery. We learned from this technique that it is possible to reach the heart valves from both the antegrade and retrograde direction, and that we can use different balloon systems mounted on one or two guidewires, double balloons, or special types of balloon, to increase valve area. These procedures have been shown to be safe, temporary flow occlusion is not a major problem, the risk of embolization is low, and complications arising from catheter use (dissection, perforation, tears, rips, and bleeding) are uncommon if the procedure is done correctly. For treatment of stenotic lesions, balloon techniques have proven effective in mitral, tricuspid, and pulmonary valve procedures. However, the mediumand long-term outcomes of treatment of stenotic and calcified aortic valves are not acceptable. In this case, the indications are limited to patients who would be at high surgical risk, particularly those with associated diseases (renal and respiratory diseases, cancer, etc) in whom cardiorespiratory arrest with extracorporeal circulation is not possible. The development of extracorporeal circulation has allowed safe replacement of native heart valves, with an acceptably low surgical mortality. However, the valves that can be used in valve replacements are limited by strict requirements. The valves implanted should be biocompatible, nonthrombogenic, long-lasting, silent, and resistant. They should also be available in many sizes, be firmly attached, have a low hemodynamic resistance, Percutaneous Treatment of Heart Valves José Antonio Condadoa,b and Bruno Burgerb