Correction of Aortic Insufficiency With an External Adjustable Prosthetic Aortic Ring

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.

An external open ring for isolated aortic valve repair

Experience with repair of isolated aortic insufficiency (AI) is increasing, encouraged by the results of valve-sparing procedures. Current techniques associate the treatment of cusp prolapse with the reduction of the almost constantly dilated aortic annular base diameter. Although few series provided satisfying mid-term results in selected patients, the lack of standardization limits their widespread use. We developed a standardized aortic valve repair procedure for isolated AI (sinuses of Valsalva ≪40 mm), combining cusp repair with a subvalvular external aortic ring annuloplasty. Alignment of cusp free edges and resuspension of the cusp effective height are performed prior to implantation of the external subvalvular ring. The prosthetic ring is of an open configuration to allow its placement externally to the aorta and below the coronary arteries without detaching them from the aortic wall. Ring size is undersized by one size relative to annular base inner diameter measured intraoperatively. The aim of the ring is to reduce the dilated aortic annular base diameter while increasing coaptation height.