The transcatheter route is an emerging approach to treating valvular disease in high-risk patients. The 1st clinical antegrade transcatheter placement of an aortic valve prosthesis was reported in 2002. We describe the first retrograde transcatheter implantation of a new aortic valve prosthesis, in a 62-year-old man with inoperable calcific aortic stenosis and multiple severe comorbidities. Via the right femoral artery, a Cook introducer was advanced into the abdominal aorta. The aortic valve was crossed with a straight wire, and a pigtail catheter was advanced into the left ventricle to obtain pressure-gradient and anatomic measurements. An 18-mm valvuloplasty balloon was then used to predilate the aortic valve. Initial attempts to position the prosthetic valve caused a transient cardiac arrest. Implantation was achieved by superimposing the right coronary angiogram onto fluoroscopic landmarks in the same radiographic plane. A balloon-expandable frame was used to deliver the valve. After device implantation, the transvalvular gradient was <5 mmHg. The cardiac output increased from 1 to 5 L/min, and urine production increased to 200 mL/h. The patient was extubated on the 2nd postimplant day. Twelve hours later, he had to be reintubated because of respiratory distress and high pulmonary pressures. His condition deteriorated, and he died of biventricular failure and refractory hypotension on day 5. Despite the severe hypotension, valve function was satisfactory on echo-Doppler evaluation. In our patient, retrograde transcatheter implantation of a prosthetic aortic valve yielded excellent hemodynamic results and paved the way for further use of this technique in selected high-risk patients.