Melody valve-in-ring procedure for mitral valve replacement: feasibility in four annuloplasty types

Abstract

Background: The recurrence of regurgitation after surgical mitral valve (MV) repair remains a significant clinical problem. Mitral annuloplasty rings are commonly used in MV repair procedures. The purpose of this study was to demonstrate the feasibility of transvenous valve-in-ring (VIR) implantation using the Melody valve (Medtronic, Minneapolis, MN), which is a valved-stent designed for percutaneous pulmonary valve replacement, and 4 distinct types of annuloplasty ring (AR) in an ovine model.

Methods: Ten sheep underwent surgical MV annuloplasty ring placement (n=10): CE-Physio, Edwards Lifesciences, Irvine, CA [n=5]; partial ring [n=3]; flexible ring [n=1]; and saddle ring [n=1]). All animals underwent cardiac catheterization, hemodynamic assessment, and Melody VIR implantation through a transfemoral venous, transatrial septal approach 1 week after surgery. Follow-up hemodynamic, angiographic, and echocardiographic data were recorded.

Results: Melody VIR implantation was technically successful in all but 1 animal. In this animal a 26-mm partial AR proved too large for secure anchoring of the Melody valve. In the remaining 9 animals, fluoroscopy showed the Melody devices securely positioned within the annuloplasty rings. Echocardiography revealed no perivalvular leak, and angiography revealed no left ventricular outflow tract obstruction, vigorous left ventricular function, and no aortic valve insufficiency. The median procedure time was 55.5 (range, 45 to 78) minutes.

Conclusions: This study demonstrates the feasibility of a purely percutaneous approach to MV replacement in patients with preexisting annuloplasty rings, regardless of ring type. This approach may be of particular benefit to patients with failed repair of ischemic mitral regurgitation.

Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Figure 1 shows fluoroscopic images of the 4 types of annuloplasty rings used for the Melody VIR procedure, including: complete rigid rings (A); partial rings (B); flexible rings (C), and saddle rings (D). Photos of each ring are shown in the insets.

Figure 2

Figure 2 shows the transvenous, transeptal approach to Melody Valve-in-Ring (VIR) delivery. The Melody device is crimped on the delivery balloon and advanced from the femoral vein, across the atrial septum and positioned centrally in the partial annuloplasty ring. Next, the Melody valve is deployed via balloon inflation. Follow-up angiography reveals no significant mitral regurgitation, no left ventricular outflow tract obstruction, and no aortic valve insufficiency. (LV = Left Ventricle)

Figure 3

Row A shows the intraoperative images following surgical Mitral annuloplasty with 4 different types of annuloplasty ring. Row B shows necropsy pictures of the atrial side of the Melody Valve-in-Ring complex. Note that there is a complete circumferential seal formed between the Melody valve and the annular tissue, even in the absence of a complete ring (column 2). Row C shows the necropsy pictures of the ventricular side of the Melody Valve-in-ring complex. In all cases, the Mitral leaflet tissue “hugs” the outside of the Melody device. Although the Melody valve leaflets appear “knarled” and “rolled”, in most cases the valves functioned well, with only one having hemodynamically significant Mitral regurgitation.