Haemodynamic performance of a 16-mm Carbomedics aortic prosthesis

A 55-year-old lady underwent repeat aortic valve replacement using a 16-mm Carbomedics prosthesis. She made an uneventful postoperative recovery and now leads an unrestricted life. Doppler echocardiography reveals a 21-mm Hg gradient across the valve at rest. This did not increase with an infusion of 30 mcg/kg per min of dobutamine, which resulted in an increase in the cardiac output from 1.96 to 5.46 l/min.