Abstract 20053: Strong Regenerative Potential of Autologous Vascularized Matrix for Atrial Patch Replacement
Background: Several patch materials are used to replace diseased cardiac tissue segments. Most of these conduits represent either non-viable materials or bio-artificial grafts with high susceptibility to infection, tissue degeneration and calcification. Hereby, we present our experience of using autologous vascularized matrix (AutoVaM) as a viable graft for myocardial tissue repair.
Methods and Results: AutoVaM patches based on small bowel segments without mucosa with adjacent jejunal artery and vein were used for the replacement of right atrial (RA) defects (2x3 cm) in pigs (n=6).
The AutoVaMs were revascularized by connecting jejunal vessels to the right internal thoracic artery and vein. Intraoperative angiography revealed regular blood perfusion of the patches. Autologous pericardium grafts were used as controls (N=6). Complications such as bleeding, graft rupture or dislodgement did not occur. Histological investigations (up to 6 months) by using Nkx 2.5 and myosin heavy chain revealed newly formed cardiomyocytes inside of AutoVaM explants mostly localized in a disseminated pattern in close proximity to mesenteric capillaries. With increasing time these cells showed strong tendency to form islets and to communicate with each other via Connexin 43 containing gap-junctions. In contrast, pericardial patches appeared as a fibrotic tissue with no evidence of myocytes inside the patch.
Based on these experimental results, 2 patients, one with myocardial sarcoma and one with thymus-carcinoma with atrial involvement underwent subtotal resection of the RA. Resulting defects were grafted using AutoVaM. No signs of thromboembolic complications or endocarditis were observed. Follow-up angiography revealed patent jejunal vessels and permeable capillary bed of the cardiac neo-chamber. Transesophageal Echocardiography (TEE) revealed systolic and diastolic motion of the graft along with the left atrium during the cardiac cycle. In one patient 2 years follow-up TEE showed an RA ejection fraction of 25%.
Conclusion: RA replacement with vascularized intestinal graft is more superior then pericardium in terms of higher regenerative potential by repopulation with cardiomyocytes. The procedure is clinically safe and promising.
Author Disclosures: S. Cebotari: None. I. Tudorache: None. S. Kostin: None. M. Karck: None. T. Meyer: None. O. Teebken: None. C. Fegbeutel: None. C. Bara: None. S. Sarikouch: None. A. Hilfiker: None. A. Haverich: None.
- © 2014 by American Heart Association, Inc.