Mitroaortic Curtain Replacement

Involvement of the mitroaortic curtain as a complication of infective endocarditis constitutes a serious medical condition. Extensive surgical debridement and mitroaortic curtain reconstruction is required in order to eradicate the infection. The fact that most of affected patients have had previous valve replacements brings additional challenges regarding optimal surgical exposure of the mitral valve annulus. In this case, the authors sectioned the superior vena cava to expose the left atrium roof and the mitral valve.

The authors have found this approach to be particularly beneficial in cases of infective endocarditis or extensive calcification of the mitroaortic curtain. In the case presented, the exposure was optimal and allowed for complex surgical reconstructions. This approach might be considered as a reasonable alternative to carry out complex reconstructions of the intervalvular fibrous body, particularly in patients with multiple previous cardiac operations.

Surgical Technique:

1. Cardiopulmonary bypass was established via ascending aorta and bi-caval cannulation (inferior vena cava through the right femoral vein).
2. The prosthethic aortic valve was excised via a hockey stick aortotomy extended down to the non-coronary sinus.
3. The incision was extended on the roof of left atrium, unifying it with the aortotomy.
4. The mitral valve was resected because it was involved in the endocarditis process. The superior vena cava was transected in order to expose the mitral annulus. Valve stitches were placed in the mitral annulus and the valve replacement was done. In some cases a pericardial patch is used to reinforce the posterior annulus.
5. A two-tongued glutaraldehyde-treated patch of bovine pericardium was used to reconstruct the mitroaortic curtain. The sutures to secure the patch were anchored in this area as described by David et al (1). However, the authors do not cut the confluence of the patch in a circular fashion. The sides of the patch were sutured to the lateral and medial fibrous trigones with 4.0 polypropylene suture (Prolene®, Ethicon, New Jersey, USA).
6. After the patch was seated, the posterior tongue was used for reconstruct the roof of left atrium.
7. The anterior tongue of the patch was incorporated within the aortic valve stitches using 2.0 polyester sutures (TiCron®, Covidien, Dublin, Irland). In this case the authors performed a Bentall procedure, but in cases that the aortic root is preserved, the anterior tongue of the patch is use to close the aortotomy.

References:

1. David TE, Kuo J, Armstrong S. Aortic and Mitral valve replacement with reconstruction of the intervalvular fibrous body. J Thorac Cardiovasc Surg 1997; 114: 766-772.