In vitro investigation of aortic valve annuloplasty using prosthetic ring devices

OBJECTIVES: The remodeling of the dilatated valve annulus with a prosthetic ring for the repair of valve insufficiency is a well-established concept in mitral valve surgery, and may also be suitable for aortic valve reconstruction. In this study, two models of prosthetic aortic annuloplasty devices were investigated. METHODS: Fresh porcine aortic roots (n=16) were investigated in a pulsatile flow simulator after patch dilatation of the annulus and subsequent reconstruction using both an external and an internal prosthetic ring. For each configuration, leakage was determined by ultrasonic flow measurements and leaflet co-aptation by transesophageal echocardiography. In addition, valves' motions were recorded by high-speed video. RESULTS: By the use of the prosthetic annuloplasty rings, leakage volumes decreased significantly compared with the dilatated root, more pronounced with the intra-annular ring. Similarly, the co-aptation height of the leaflets increased. Pressure gradients were not significantly influenced by the ring application, but leaflet motion patterns changed from the usual trapezoid to a more rectangular opening characteristic, visible at both echocardiographic and high-speed video analysis. CONCLUSIONS: The reconstruction of a dilatated aortic valve annulus using external and internal ring devices is feasible and effective for reduction of regurgitation at which the internal ring provides a greater potential to decrease valve insufficiency.