Suture Relocation of the Posterior Papillary Muscle in Ischemic Mitral Regurgitation

Carpentier’s type I leaflet dysfunction. Mitral annular dilation results in failure of leaflet coaptation and a broad central jet of mitral regurgitation.

Carpentier’s type IIIb leaflet dysfunction. Posterior displacement of the posterior papillary muscle causes tethering of the A3 and P3 segments of the mitral valve, resulting in an eccentric jet of mitral regurgitation.

Ring annuloplasty. The mitral ring is sized with ring sizers measuring the intertrigonal distance (usually 26-28 mm). Ten to 12 annuloplasty sutures are generally used and are placed in horizontal mattress fashion around the mitral annulus.

Ring annuloplasty (cont’d). A complete semirigid ring is used. Sutures are passed through the ring fabric at appropriate intervals to produce an even annular reduction. This results in proper coaptation of the anterior and posterior leaflets.

Posterior papillary muscle relocation. Mitral repair begins with preoperative and intraoperative echocardiographic assessment of the mechanism of mitral regurgitation, confirming regurgitation secondary to type IIIb leaflet motion. The amount of leaflet tethering is estimated by intraoperative transesophageal echocardiography. With a standard left atrial approach, the head of the posterior papillary muscle is relocated anteriorly by passing both needles of a 3-0 polypropylene suture through the fibrous portion of the posterior papillary muscle tip. Unless the papillary muscle tip is particularly fibrous, a pledgetted suture is used. Each needle of the double armed 3-0 prolene is then passed up through the adjacent mitral annulus usually posterior to the right fibrous trigone at P3. The final position of the posterior papillary muscle tip is estimated by determining the point at which leaflet coaptation occurs in the plane of the mitral annulus. Mitral annuloplasty is then performed as previously described. The adequacy of repair is tested with the left ventricular saline infusion test and the repair completed by ring placement as described above, if the valve is competent.

Dor procedure and relocation of the papillary muscle tip. In cases where the left ventricle is markedly enlarged, a Dor procedure is added to both stabilize the position of the papillary muscles and prevent late apical migration of the subvalvular apparatus. Surgical location of the posterior papillary muscle tip is performed through the left ventricle in these cases. The typical ventriculotomy parallel to the left anterior descending artery is made generally within the area of myocardial thinning. This is usually about 1 fingerbreadth lateral to the artery as it courses toward the apex of the heart.

Dor procedure and relocation of the papillary muscle tip (cont’d). Via the left ventricular exposure, the posterior papillary muscle stitch (3-0 polypropylene) is placed first through the head of the papillary muscle and then through the adjacent posterior mitral annulus. The suture is then tied on the ventricular side.

Dor procedure and relocation of the papillary muscle tip (cont’d). One or 2 concentric Fontan stitches are then placed at the border zone between viable left ventricular myocardium and scar.

Dor procedure and relocation of the papillary muscle tip (cont’d). The left ventriculotomy is closed with a 3-0 polyproylene running double layer closure buttressed 2 felt strips.