Percutaneous aortic valve replacement is becoming a reality and brings new hope for a number of patients who cannot currently be treated with traditional surgical techniques.
Whereas surgical valve replacement concerns about 200,000 patients worldwide every year, it is estimated that between 1/3 (Iung et al, Euro Heart Survey, 2003) and 2/3 (Rambas Pai, USC AHA 2004) of patients do not receive surgery due to either excessive risk factors and comorbidities or patient refusal due to fear of lifestyle changes following heavy surgery in elderly patients. The size of this untreated cohort is expected to increase, reflecting the aging population. However, without replacing the valve, the disease is associated with a very high mortality rate (50 to 60% at one year) beyond the onset of symptoms. The goal of the percutaneous valve is to bring a less invasive therapeutic solution for these patients.
The Cribier-Edwards Percutaneous valve (Edwards Lifesciences, Irvine, Cal, USA) is a bioprosthesis made of three leaflets of equine pericardium sutured to a balloon expandable stainless steel stent. After balloon predilatation of the native valve, this bioprosthesis is crimped over a balloon catheter, and advanced over a stiff guidewire through the vessels (either from the femoral vein –antegrade/transseptal approach- or the femoral artery –retrograde approach-) up to the diseased fibro-calcific native aortic valve, using regular cardiac catheterization techniques. The bioprosthesis is then released by balloon inflation at mid-part of the native valve. In our institution, the technique is performed under local anesthesia and light sedation.
Gina Dellios | EurekAlert!
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