1. Anterior Mitral Valve Leaflet Augmentation Repair in Type III Mitral Regurgitation: Lessons Learned Thomas Kelley, Jr., James McCarthy, He Wang, Nels D. Carroll, Mohammed Kashem, G William Moser, Yoshiya Toyoda, Grayson H. Wheatley, Larry Kaiser,T. Sloane Guy

2. The views in this presentation are those of the authors and do not represent those of the DOD or U.S. Army Senior author is consultant for Medtronic® and Edwards Lifesciences Disclosures

3. Type III MR: The Problem Carpentier Type III MR is plagued by high recurrent MR rate. Various strategies have been attempted without proven long-term success. Replacement is becoming mainstream option, particularly for IMR. Contributing issues include poor leaflet coaptation, poor leaflet tissue, and ventricular remodeling.

4. Simple Technique for Leaflet Augmentation Artwork: Aubert, S., Flecher, E., Rubin, S., Acar, C., & Gandjbakhch, I. (2007). Anterior Mitral Leaflet Augmentation With Autologous Pericardium. The Annals of Thoracic Surgery,83, 1560-1561

5. Minimally Invasive Robotic Approach (22/25 patients) Robotic port placementEndovascular bypass

6. CorMatrix® Extracellular matrix (ECM) produced from porcine small intestine submucosa. Early animal and human studies with valve repair demonstrated good function and evidence of reabsorption. Largest published study in adults using this material for mitral leaflet repairs reported patch issues in 2 of 19 cases (10.5%)

7. Echo Images Intra-operative Pre-repairPost-repair

8. Study Single center retrospective from 2012-13. 25 patients had anterior leaflet augmentation with CorMatrix. All repairs were for Type III MR. Mean age 63.3 ± 12.2 years, 9 males (36%). Mean follow up of 10.6 months. No more than trace MR at discharge in all patients

9. Results Recurrence of severe MR in 8 patients (32%) Mean time to recurrence 219 days 7 elected for re-operation 5 patients had re-do mitral valve replacement 2 re-do repairs of redundant graft tissue: both then failed due to patch dilatation. Univariate analysis – Only BMI <30 correlated with failure (28.1 vs 34.5 p =.039)

10. Results Variables Graft Success (n) Graft Failure (n) p value Age (Years)64.6 ± 11.261.8 ± 13.5p=0.67 Gender p=0.99 Males72 Females106 Body Mass Index (kg/m 2 ) 34.6 ± 6.928.1 ± 5.8p=0.03 Diabetes42p=0.25 COPD32p=0.75 Hypertension147p=0.99 LVEF (%)49.4 ± 14.751.1 ± 13.9p=0.51 Robotic Approach157p=0.99 Annuloplasty band size (mm) 27.2 ± 3.027.6 ± 3.2p=0.77

11. Modes of Failure

12. Pathology: Explanted Tissue Example ECM patch highlighted in red

13. Pathology - Explanted Patch With Little Evidence of Host Integration 40x Magnification 100x magnification Native MV tissue with inflammation ECM (collagen only) ECM

14. Immunohistological Stain for M2 Macrophage Response CD-68+ macrophages (All Macrophages) CD-163+ Macrophages (M2 only)

15. Conclusions For Type III MR, large patch leaflet augmentation with CorMatrix® was associated with a 32% rate of recurrent MR due to patch dysfunction. Possibly contributing factors include large patch size creating excessive stress on the patch, suture selection, product failure, immunologic factors.