HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Muralidhar Padala Vinod H. Thourani Ajit P. Yoganathan David H. Adams Permission Requests Google Scholar Articles by Padala, M. Articles by Adams, D. H. PubMed Articles by Padala, M. Articles by Adams, D. H. Related Collections Valve disease

J Thorac Cardiovasc Surg 2009;138:309-315
© 2009 The American Association for Thoracic Surgery

Acquired Cardiovascular Disease

Mitral valve hemodynamics after repair of acute posterior leaflet prolapse: Quadrangular resection versus triangular resection versus neochordoplasty

^a Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
^b Division of Cardiothoracic Surgery, Emory University School of Medicine, Atlanta, Ga
^c Department of Cardiothoracic Surgery, Mt Sinai School of Medicine, New York, NY

Received for publication May 13, 2008; revisions received December 9, 2008; accepted for publication January 13, 2009.

^_* Address for reprints: Ajit P. Yoganathan, PhD, The Wallace H. Coulter Distinguished Faculty Chair in Biomedical Engineering and Regents Professor, Associate Chair for Research, Wallace H. Coulter School of Biomedical Engineering, Georgia Institute of Technology and Emory University, Room 2119 U. A. Whitaker Building, 313 Ferst Dr, Atlanta, GA 30332-0535. (Email: ajit.yoganathan{at}bme.gatech.edu).

Objective: Leaflet prolapse resulting from acute chordal rupture is one presentation of fibroelastic deficiency that is associated with minimal leaflet changes in the prolapsing segment. Minimizing resection and preserving leaflet tissue may be an optimal surgical strategy. We examined the importance of the leaflet preservation concept by comparing resective and nonresective surgical procedures in practice today.

Methods: Eight porcine mitral valves were evaluated in an in vitro heart simulator before surgical manipulation. Mitral regurgitation was created in these valves by transecting the posterior marginal chordae resulting in severe P2 prolapse. After confirmation of mitral regurgiation via regurgitant flow measurement (mL/beat), regurgitation was corrected by three repairs: neochordoplasty with polytetrafluoroethylene sutures (Gore-Tex; W. L. Gore & Associates, Inc, Flagstaff, Ariz), triangular resection, and quadrangular resection with annular compression. Postrepair valve hemodynamics were quantified under pulsatile conditions of 120 mm Hg peak transmitral pressure and 5 L/min cardiac output at 70 beats/min. Furthermore, hemodynamic, geometric, and echocardiographic indices were measured.

Results: Transecting the marginal chordae resulted in severe P2 prolapse and significant mitral regurgiation (19.3 ± 4.3 mL/beat). Regurgitant volume was significantly reduced after any of the three surgical approaches (quadrangular, 4.38 ± 1.6 mL/beat; triangular, 2.56 ± 1.0 mL/beat; neochordal, 2.86 ± 1.24 mL/beat). In comparison with the baseline normal valves, leaflet coaptation length and posterior leaflet mobility were significantly reduced in the quadrangular resection group, whereas they were partially restored in the triangular resection and fully preserved in the neochordoplasty group.

Conclusions: Although the three repair procedures are hemodynamically comparable, valve function and leaflet kinematics were significantly better after a nonresection or limited resective correction of leaflet prolapse in this experimental model of acute chordal rupture with otherwise normal leaflet geometry.