Senile calcific aortic stenosis (AS) is the most common acquired valvular heart disease with an increasing prevalence attributable to an aging population. Survival is poor in patients with severe or critical AS, chiefly after the onset of symptomology that primarily includes angina, dyspnea, or syncope. On the onset of symptoms, mortality occurs at very high rates during the ensuing 2 to 3 years.1 Until recently, surgical aortic valve replacement represented the sole therapy that definitive reduced mortality and morbidity in patients with severe symptomatic AS, with medical therapy generally ineffective of these patients. Given the advanced age commonly associated with severe AS, a high proportion of these patients are denied surgical intervention because of multiple comorbidities and excessively high surgical risk.2 Recently, transcatheter aortic valve replacement (TAVR) has emerged as a novel disruptive technology that serves an alternative therapy to surgical AVR and has been shown to be an effective therapy in nonoperable and high-risk patients with severe symptomatic AS.3,4 TAVR was first described in humans by Cribier et al in 20025 by a transvenous approach delivered in an antegrade fashion. This technique requires a transseptal puncture and passage of the aortic stent valve across the mitral valve to the aortic position. Subsequently, array of alternative transvascular approaches have arisen, including transfemoral, transaortic, trans-subclavian, and aortic methods. Of these, the retrograde transarterial approach through the femoral artery, developed by Webb et al,6 has been the commonly used approach, with >60 000 such procedures performed worldwide to date. To date, the global experience with TAVR as documented in both single and multicenter registries as well as through multicenter trials have shown good clinical outcomes with improvement in hemodynamic and clinical status, establishing TAVR to be a feasible alternative therapy to traditional surgical aortic valve …
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