CONGRESS ABSTRACT

PREMISE: managing of mitral annular calcification (MAC) in mitral repair surgery (MRS) remains debated and exciting. The MAC’s pathophysiology in MV prolapse knows many and complex mechanisms: 1st step in MAC genesis is related to the abnormal MV geometry and mechanics, especially of the posterior mitral leaflet (PL). In bileaflets MV prolapse, PL acts anomaly like the arm of a grade 1-lever, spreading systolic energy to the muscle tissue in the MV hinge area, thus creating the curling. In this area the muscle tissue is exposed to abnormal systo-diastolic shear forces, which firstly trigger apoptosis, followed by fibrosis and later by calcification. In a normal MV geometry, PL acts as an arm of 3-grade lever. A 67-yo woman, without comorbidity, with dyspnea 2nd NYHA class, having severe MR and severe MAC is presented. TT & TOE echo showed (fig 1,2) bileaflets prolapse, severe MR (ERO 0,4mm2, RV 68mL) and severe MAC infiltrating LV wall, alongside of the posterior annulus (PA). MR presents more jets: the most important at A1→P1 scallops. The MV geometry showed loss of the coaptation triangle – with coaptation sited inside of the left atrium, which was harshly dilatated (97 mL/m2 BP). LV was normal with 62% EF, but the antero-posterior annulus was dilated: 44mm. CT scan showed normal coronaries and severe calcification involving PA -Fig 1D. Despite the complex anatomy, it was decided to perform MRS by right minitoracotomy with endoscopic 3D system, our routine approach for MRS. Intraoperatively important calcifications along the PA were found, prolapse of A1→P1 scallops and a large P2→P1 cleft. Loss of MV coaptation was corrected by an unusual anterior annuloplasty -Fig 2A, using an incomplete flexible band (Cosgrove n.32) on anterior annulus – which wasn’t calcified. Additional paracommissural E-2-E stitches was necessary to fix A1→P1 prolapsing area and to close the P2→P1 cleft. Thus, it was possible to perform the annuloplasty, simplifying the procedure without incurring the risks of decalcification and/or MV replacement. The TOE showed a good result with mild MR. Uneventful postoperative course.Take Home message: in cases of important MAC, an anterior annuloplasty could be a valuable option to reduce the diameter of MV annulus and improve the coaptation without going against the risks of decalcification like AV groove disruption, AV block, coronary injury and stroke. The technique can be related to any other leaflet procedure requested