Edge-to-edge mitral repair: tension on the approximating suture and leaflet deformation during acute ischemic mitral regurgitation in the ovine heart

• Published in: Circulation (New York, N.Y.) N.Y.), 2001-09, Vol.104 (12 Suppl 1), p.I29-I35
• Main Authors: Nielsen, S L, Timek, T A, Lai, D T, Daughters, G T, Liang, D, Hasenkam, J M, Ingels, N B, Miller, D C
• Format: Article
• Language: English
• Subjects: Acute Disease; Animals; Cardiac Surgical Procedures; Diastole; Disease Models, Animal; Echocardiography, Doppler; Echocardiography, Doppler, Color; Fluoroscopy - methods; Hemodynamics; Mitral Valve - diagnostic imaging; Mitral Valve - physiopathology; Mitral Valve - surgery; Mitral Valve Insufficiency - complications; Mitral Valve Insufficiency - diagnosis; Mitral Valve Insufficiency - physiopathology; Mitral Valve Insufficiency - surgery; Multivariate Analysis; Myocardial Ischemia - complications; Sheep; Stress, Mechanical; Suture Techniques; Systole
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.104.suppl_1.I-29

Edge-to-edge approximation of the mitral valve leaflets (Alfieri procedure) is a novel surgical treatment for patients with ischemic mitral regurgitation (IMR). Long-term durability may be limited if abnormal mitral leaflet stresses result from this procedure. The aim of the current study was to measure Alfieri stitch tension (F(A)) and to explore its geometric determinants in an ovine model of acute IMR as a reflection of the mitral leaflet stresses imposed by the procedure. Eight sheep were studied immediately after surgical placement of (1) a force transducer interposed between sutures approximating the central leaflet edges and (2) radiopaque markers around the mitral annulus and leaflet edges. Computer-aided analysis of videofluorograms was used to obtained 3D marker coordinates. Simultaneous measurements of F(A), septal-lateral annular dimension (L(S-L)), leaflet edge separation (L(SEP)), anterior (L(AL)) and posterior (L(PL)) leaflet length, and hemodynamic variables were obtained at baseline (CTL) and during acute IMR (circumflex artery occlusion). F(A) was significantly elevated throughout the cardiac cycle during IMR compared with CTL, with maximum F(A) in diastole (0.26+/-0.05 versus 0.46+/-0.08 N, CTL versus IMR; P