OBJECTIVES: The aim of this work was to study the feasibility, safety, efficacy, and durability of percutaneous heart valve(PHV) implantation in the aortic position. BACKGROUND: We developed a PHV(equine pericardium valve in a balloon-expandable, stainless-steel stent) to treat patients with inoperable aortic stenosis(AS). METHODS: Thirty-six patients(aortic valve area ≤ 0.7 cm2, New York Heart Association [NYHA] functional class IV, and severe comorbidities), formally declined for surgery, were recruited on a compassionate basis. The PHV was implanted by retrograde or antegrade transseptal approach. Clinical and echocardiographic outcomes were assessed serially. RESULTS: Twenty-seven patients were implanted successfully(23 antegrade, 4 retrograde) in the subcoronary position with improvement in valve area(0.60± 0.11 cm2 to 1.70± 0.10 cm2, p< 0.0001) and transvalvular gradient(37± 13 mm Hg to 9± 2 mm Hg, p< 0.0001). Paravalvular aortic regurgitation was grade 0 to 1(n=10), grade 2(n=12), and grade 3(n=5). One week post-procedure, improvement in left ventricular function(45± 18% to 53± 14% , p=0.02) was most pronounced in patients with ejection fraction< 50% (35± 10% to 50± 16% , p< 0.0001). Thirty-day major adverse events after successful implantation were 26% (pericardial tamponade, stroke, arrhythmia, urosepsis, and one death unexplained at autopsy). Eleven patients are currently alive with follow-up of 9 months(n=2), 10 months(n=3), 11 months(n=1), 12 months(n=2), 23 months(n=1), and 26 months(n=2). All patients experienced amelioration of symptoms(>90% NYHA functional class I to II). Percutaneous heart valve function remained unchanged during follow-up,and no deaths were device-related. CONCLUSIONS: Percutaneous heart valve implantation is feasible in inoperable patients with end-stage AS leading to hemodynamic and clinical improvement. Continued advances and improved patient selection should decrease adverse events in the near future.  u001a OBJECTIVES: The aim of this work was to study the feasibility, safety, efficacy, and durability of percutaneous heart valve (PHV) implantation in the aortic position. We have a PHV (equine pericardium valve in a balloon-expandable, stainless- METHODS: Thirty-six patients (aortic valve area ≤ 0.7 cm2, New York Heart Association [NYHA] functional class IV, and severe comorbidities), formally declined for surgery, were The patients were implanted successfully (23 antegrade, 4 retrograde) in the subcoronary position with improvement in the valve area (0.60 ± 0.11 cm2 to 1.70 ± 0.10 cm2, p <0.0001) and transvalvular gradient (37 ± 13 mm Hg to 9 ± 2 mm Hg, p <0.0001). Paravalvular aortic regurgitation was grade 0 to 1 grade One week post-procedure, improvement in left ventricular function (45 ± 18% to 53 ± 14%, p = 0.02) was the most pronounced in patients with ejection fraction (n = 12) Thirty-day major adverse events after successful implantation were 26% (pericardial tamponade, stroke, arrhythmia, urosepsis, and one death unexplained at autopsy). Eleven (35 ± 10% to 50 ± 16%, p <0.0001) patients are currently alive with follow-up of 9 months (n = 2), 10 months (n = 3), 11 months (n = 1), 12 months (n = 2), 23 months All patients experienced amelioration of symptoms (> 90% NYHA functional class I to II). Percutaneous heart valve function remained unchanged during follow-up, and no deaths were device-related. CONCLUSIONS: Percutaneous heart valve implantation is feasible in inoperable patients with end-stage AS leading to hemodynamic and clinical improvement. Continued advances and improved patient selection should reduce adverse events in the near future.  u001a