title: Septal-lateral annular cinching abolishes acute ischemic mitral regurgitation.
abstract: OBJECTIVE
  Ring annuloplasty prevents acute ischemic mitral regurgitation in sheep, but it also abolishes normal mitral annular and posterior leaflet dynamics. We investigated a novel surgical approach of simple septal-lateral annular cinching with sutures to treat acute ischemic mitral regurgitation.
  
  
  METHODS
  Nine adult sheep underwent implantation of multiple radiopaque markers on the left ventricle, mitral anulus, and mitral leaflets. A septal-lateral transannular suture was anchored to the midseptal mitral anulus and externalized to a tourniquet through the midlateral mitral anulus and left ventricular wall. Open-chest animals were studied immediately postoperatively. Acute ischemic mitral regurgitation was induced by means of proximal left circumflex artery snare occlusion, and 3 progressive steps of septal-lateral annular cinching (each 2-3 mm suture tightening for 5 seconds) were performed with the transannular suture. Biplane videofluoroscopy for 3-dimensional marker coordinates and transesophageal echocardiography were performed continuously before and during left circumflex ischemia and septal-lateral annular cinching.
  
  
  RESULTS
  Acute left circumflex ischemia caused ischemic mitral regurgitation (+0.5 +/- 0.4 [baseline] vs +2.0 +/- 0.7 [ischemia]; P =.005; scale, +0-4), which decreased progressively with each step of septal-lateral annular cinching and was eliminated during the third step (ischemic mitral regurgitation, +0.6 +/- 0.5; P = not significant vs baseline). The third step of septal-lateral annular cinching decreased the septal-lateral diameter by 6.0 +/- 2.6 mm (P =.005); however, mitral anulus area reduction (8.5% +/- 1.0% and 6.9% +/- 1.9% for ischemic mitral regurgitation and septal-lateral annular cinching step 3, respectively; P =.006) and posterior leaflet excursion (50 degrees +/- 9 degrees and 44 degrees +/- 11 degrees for regurgitation and annular cinching step 3, respectively; P =.002) throughout the cardiac cycle were affected only mildly. Normal mitral annular 3-dimensional shape was maintained with septal-lateral annular cinching.
  
  
  CONCLUSIONS
  Isolated 22% +/- 10% reduction in mitral annular septal-lateral dimension abolished acute ischemic mitral regurgitation in normal sheep hearts while allowing near-normal mitral annular and posterior leaflet dynamic motion. Septal-lateral annular cinching may represent a simple method for the surgical treatment of ischemic mitral regurgitation, either as an adjunctive technique or alone, which helps preserve physiologic annular and leaflet function.
authors.affiliation: Department of Cardiovascular Surgery and the Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, Calif, USA.
authors.forename: Tomasz A
authors.initials: TA
authors.lastname: Timek
authors.forename: David T
authors.initials: DT
authors.lastname: Lai
authors.forename: Frederick
authors.initials: F
authors.lastname: Tibayan
authors.forename: David
authors.initials: D
authors.lastname: Liang
authors.forename: George T
authors.initials: GT
authors.lastname: Daughters
authors.forename: Paul
authors.initials: P
authors.lastname: Dagum
authors.forename: Neil B
authors.initials: NB
authors.lastname: Ingels
authors.forename: D Craig
authors.initials: DC
authors.lastname: Miller
mesh_terms: D000208:Acute Disease; D000704:Analysis of Variance; D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006439:Hemodynamics / Q000502:physiology; D008297:Male; D008943:Mitral Valve / Q000503:physiopathology / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000503:physiopathology / Q000601:surgery*; D017202:Myocardial Ischemia / Q000150:complications / Q000601:surgery*; D011336:Probability; D012680:Sensitivity and Specificity; D012756:Sheep; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology