Melody valve to replace the mitral valve in small children: Lessons learned

Abstract

Objective: Infants requiring mitral valve replacement have few viable options. Recently, stented bovine jugular vein graft (Melody) has been surgically implanted in such cases. Herein, we report our experience, elaborating on evolution of implantation technique, pitfalls, as well as long-term outcome (including late dilatability).

Methods: Seven Melody valves were implanted (2013-2019). The median patient age and weight were 6.7 (1.8-30.5) months and 5.8 (4.6-9.5) kg, respectively. The indications for implantation were mitral stenosis and/or regurgitation postatrioventricular septal defect (AVSD) repair (5), congenital mitral valve dysplasia (1), and Shone's complex (1). Operative technique involved shortening the valve and creating a neo-sewing ring at 2/3 (atrial)-1/3 (ventricular) junction. Implantation was followed by intraoperative balloon dilatation.

Results: Five out of seven patients survived the perioperative period (one death due to technical failure and the other due to acute respiratory distress syndrome postcardiopulmonary bypass). Two out of five medium-term survivors got transplanted (1) or died due to acute myeloid leukemia (1). No valves were replaced. The mean echo gradient at discharge was a median 4 (2-6) mmHg. None of the patients showed left ventricular outflow tract or pulmonary venous obstruction. Two Melody valves were dilated late (5 months and 3 years postoperatively), resulting in decreasing mean gradients from 6 to 1 and from 17 to 4 mmHg. At last follow-up, surviving Melody had a mean gradient of 4 (1-9) mmHg.

Conclusions: Mitral valve replacement with a Melody valve is feasible in infants, is reproducible, shows good immediate results, and offers the possibility of later dilatation. This technique offers a better solution compared to the existing alternatives for infants requiring a prosthetic mitral valve.

Keywords: Bioprosthesis; Melody valve; complete atrioventricular septal defect; congenital valvular disease; mitral valve replacement in infants and children.

Figure 1

(a) Foreshortened Melody valve by turning back the struts. (b) Creation of a neo-sewing ring at the junction of proximal 2/3^rdand distal 1/3^rdof Melody^®valve

Figure 2

Left ventricular angiogram demonstrating an unobstructed left ventricular outflow tract at 3.1 years postimplantation

Figure 3

(a) Two-dimensional echo and (b) color Doppler image of the Melody valve in mitral position at 61 months postimplantation

Figure 4

De novo left pulmonary vein ostial stenosis (red arrow) in patient 5; preceding mitral valve replacement

Figure 5

Melody valve balloon dilatation: (a) before (b) during (c) after dilatation