COmprehensive Mitral Valve Apparatus Reconstruction.

COMVAR is a surgical procedure that is developed to preserve the mitral valve.

COMVAR can treat mitral valve diseases, e.g., mitral insufficiency, mitral stenosis, and combined mitral steno-insufficiency.

COMVAR is an acronym of COmprehensive Mitral Valve Apparatus Reconstruction.

The goal of COMVAR is to reconstruct the patient's native mitral valve apparatus anatomically and physiologically, instead of resection and replacement.

Depending on the patient's pathologic conditions, all or some of the above surgical steps are performed. Mitral valve repair has been done commonly in the cardiac surgery. Nevertheless, COMVAR procedure provides the uniform standardized modality in treating various types of mitral valve diseases, preserving the native mitral valve structure as much as possible, because it restores not only mitral annulus, but also reconstructs the mitral leaflets. COMVAR procedure using the Mitra-Lift® series and COMVAR templates can be applied to the following cases. 1) Isolated mitral regurgitation Isolated mitral regurgitation is a good indication and prolapsed leaflet regardless its location (anterior or posterior, or both). 2) Isolated mitral stenosis Isolated mitral stenosis even with annular calcifications can be managed by COMVAR technique together with meticulous decalcification procedures. 3) Combined mitral regurgitation and stenosis Regardless of its causative and initiating disease, once the mitral annulus, valve leaflet, or chorda is involved pathologically, all of them are supposed to be diseased as time passes. Diseases such as mitral regurgitation, stenosis, and combined steno-insufficiency belong to this category. COMVAR technique can be successfully applied to these indications. 4) Prosthetic valve failure at the aortic position Conditions with present artificial heart valve can be indicated for COMVAR, if the patient's mitral annulus has been preserved. COMVAR procedure is composed of 4 surgical steps. 1. Restoration of mitral annulus (lifting annuloplasty) 2. Reconstruction of chordae (chordoplasty) 3. Reconstruction of mitral valve leaflets (leaflet extension) 4. Restoration of mitral commissure (commissuroplasty) ntraoperative sequence of COMVAR procedure 1. Left atriotomy (trans-atrial or trans-septal) 2. Submitral apparatus correction (chordoplasty)  3. Mitral commissurotomy in mitral stenosis (commissuroplasty)  4. Mitral leaflet extension (posterior and/or anterior) 5. Anterior annulus diameter measurement and determination 6. Posterior lifting annuloplasty 7. Removal of the product Established techniques for cardiopulmonary bypass are used in the usual manner. The followings are the specific procedures in the COMVAR procedure. COMVAR (Comprehensive Mitral Valve Apparatus Reconstruction) procedure is performed in the following order; To expose the mitral valve and chordae, left atriotomy by either trans-atrial or trans-septal approach is possible. 1.Left atriotomy Left atriotomy can be performed by either trans-atrial or trans-septal approach to expose the mitral valve structures adequately. However, in case of small left atrium or combined tricuspid pathology, trans-septal approach allows much better exposure of mitral structures. 2.Submitral apparatus correction (chordoplasty) When the chorda is torn by either endocarditis or degenerative reasons causing mitral insufficiency, neo-chordae reconstruction can be done by conventional way using PTFE sutures. 3.Mitral commissurotomy (commissuroplasty)  In case of mitral stenosis, commissurotomy can be perfomed anteriorly as well as posteriorly as needed. Fused commissures can be divided until to reach the mitral annulus (Fig.1). 4. Mitral leaflet extension -To be updated- 5. Anterior annulus diameter measurement and determination To determine the length of mitral posterior lifting annuloplasty strip (Mitra-Lift®), anterior annulus diameter should be measured from trigone to trigone using Mitral Sizers. 6. Posterior lifting annuloplasty Lifting annuloplasty is a key procedure in MR, increasing the physiologic coaptation surface in systolic phase and elevates downward displaced LV free wall. Specially designed structure of Mitra-Lift® strip is placed at the LA wall along the posterior annulus (Fig. 4). 7. Removal of the Product After operation, the implanted device can be monitored and evaluated by Transesophageal Echocardiography or Magnetic Resonance Imaging.If the implants are found to be wrongly located, or displaced after operation, implants should be removed through the previous route and re-implanted or replaced with other new implant. When endocarditis occurs in the annulus of mitral valve before neo-intima is created by the endothelialization process, implanted products are easy to be removed. Simply cut the knot of sutures on the strip and take them out. However, when endocarditis occurs after endothelialization is completed, neo-intima has to be surgically opened to remove the encapsulated strip. The other processes are same.

Advantage of COMVAR Technically Easy and SafeIn comparison with the conventional prosthetic mitral valve replacement technique, this standardized COMVAR technique helps surgeon operate in comfort. Minimizes Functional Impairment of mitral valve apparatusCOMVAR can preserve the function of mitral valve apparatus without prosthetic mitral valve replacement. Obviates Anticoagulation Anticoagulant is unnecessary; no danger of blood clots. Excellent ApplicabilityCOMVAR is applicable to all kinds of Mitral Valve diseases including severely calcified or thickened Mitral stenosis. Preserves Hemodynamics COMVAR ensures the normal function of cardiac valve and whereby it leads to ideal blood pressure and blood flow. COMVAR can also gurantee the sufficiency of mitral orifice. Improves Quality of LifeQuick recovery from surgical operation and low rate of recurrence ensure active and energetic life. Tissue Compatibility: reduces the threat of endocarditisAs COMVAR® Set is made of Dacron in form of flexible strips, it can endure repetitive contraction and relaxation of mitral annulus and does not give any stress on the tissues.