M J Thubrikar1, F Robicsek, G G Gong, B L Fowler. 1. Heineman Medical Research Laboratory and the Department of Thoracic and Cardiovascular Surgery, Carolinas Medical Center, Charlotte, North Carolina 28203, USA. mthubrikar@carolinas.org
Abstract
BACKGROUND: We designed and tested a novel aortic root prosthesis with compliant sinuses for valve-sparing operations. METHODS: In eight human aortic roots, the aorta was trimmed 2 mm above the leaflet attachment. The aortic portion of the graft was made by scalloping the Dacron tube. Three sinuses were made individually after turning z-folds in the fabric 90 degrees. Three rectangular pieces were cut and purse strings sewn in each to form the sinuses. The graft was sutured to the aortic root and studied in a left heart simulator. The leaflet motion was recorded (500 frames/second), commissural movement was measured with ultrasound, and the shape of the root was determined from a mold. Seven intact aortic roots were also studied. RESULTS: In the aortic graft roots, the valves were competent and leaflets opened rapidly into a circular orifice, not touching the sinus wall. Commissural diameter increased by 22% when pressure increased from 0 to 80 mm Hg, and increased by a further 6.6% when pressure increased to 120 mm Hg. The sinuses had a teardrop shape. CONCLUSIONS: The dynamics of the aortic graft root and the leaflets were comparable to that of the intact aortic root. This prosthesis is being introduced in clinical practice.
BACKGROUND: We designed and tested a novel aortic root prosthesis with compliant sinuses for valve-sparing operations. METHODS: In eight human aortic roots, the aorta was trimmed 2 mm above the leaflet attachment. The aortic portion of the graft was made by scalloping the Dacron tube. Three sinuses were made individually after turning z-folds in the fabric 90 degrees. Three rectangular pieces were cut and purse strings sewn in each to form the sinuses. The graft was sutured to the aortic root and studied in a left heart simulator. The leaflet motion was recorded (500 frames/second), commissural movement was measured with ultrasound, and the shape of the root was determined from a mold. Seven intact aortic roots were also studied. RESULTS: In the aortic graft roots, the valves were competent and leaflets opened rapidly into a circular orifice, not touching the sinus wall. Commissural diameter increased by 22% when pressure increased from 0 to 80 mm Hg, and increased by a further 6.6% when pressure increased to 120 mm Hg. The sinuses had a teardrop shape. CONCLUSIONS: The dynamics of the aortic graft root and the leaflets were comparable to that of the intact aortic root. This prosthesis is being introduced in clinical practice.