Invited Commentary

Abstract

Rosario-Quinones and colleagues report [1Rosario-Quinones F. Magid M.S. Yau J. Pawale A. Nguyen K. Tissue reaction to porcine intestinal submucosa (CorMatrix) implants in pediatric cardiac patients: a single-center experience.Ann Thorac Surg. 2015; 99: 1373-1378Abstract Full Text Full Text PDF PubMed Scopus (57) Google Scholar] their experience of using CorMatrix during pediatric cardiac surgery. Six of 25 patients required reoperation and pathology demonstrated inflammation and fibrosis with transient peripheral eosinophilia. It is difficult to know how to interpret these findings. The small intestinal submucosa-extracellular matrix (SIM-ECM) technology has been used in greater than 2,000,000 patients and constructive remodeling has been reported in greater than 800 scientific papers. CorMatrix has been used for reconstruction of all 4 cardiac valves, aorta and pulmonary arteries, septal defect closure, outflow tract repairs, and pericardial reconstruction. In general, clinical reports are few and the concern has been inflammation and fibrosis [2Zaidi A.H. Nathan M. Emani S. et al.Preliminary experience with porcine intestinal submucosa(CorMatrix) for valve reconstruction in congenital heart disease: histologic evaluation of explanted valves.J Thorac Cardiovasc Surg. 2014; 148 (2216-4, 2225.e1)Abstract Full Text Full Text PDF PubMed Scopus (90) Google Scholar]. Negative results reported have ranged from explanted pathology to abnormal imaging (computed tomography, magnetic resonance imaging, and echocardiography) to contraction and thickening noted at reoperation. Techniques of implantation are also variable; continuous versus interrupted suture, circumferential suture lines, eg, mid-leaflet augmentation or blood vessel reconstruction versus an exposed free edge with semilunar leaflet reconstruction, and finally anastomosis to a freshly cut normal endocardium that may be important for porcine scaffold cellularization. Despite concerning reports, CorMatrix implants now exceed 120,000 patients and feedback by many surgeons have been positive (Drs Emile Bacha, James Tweddell, ∗Drs Bacha and Tweddell are both on the Medical Advisory Board for CorMatrix.∗Drs Bacha and Tweddell are both on the Medical Advisory Board for CorMatrix. Patrick McConnell, Frank Scholl and John Kupferschmid, personal communications, February 2 and 3, 2015). Favorable comments include “soft and pliable,” “looks like the native tissue of what was reconstructed,” and “cannot differentiate between CorMatrix and adjacent native tissue.” There are some patients who react adversely to bioprosthetic valves and have early deterioration. Whether this is similar to the negative findings reported with CorMatrix is not clear. It should be emphasized that adherence to proper preparation protocols is essential as inadvertent rinsing of a bioprosthetic valve with antibiotic solution can adversely affect the leaflets [3Hu J.E. Gilmer L. Hopkins R. Wolfinbarger Jr., L. Effects of antibiotics on cellular viability in porcine heart valve tissue.Cardiovasc Res. 1990; 24 ([Erratum]): 168Crossref Scopus (16) Google Scholar]. There is a need for a prosthetic that will remodel, grow, and not calcify. Current materials include synthetic, cross-linked, or glutaraldehyde-treated and all are non-growing. Basic science evidence has demonstrated CorMatrix to be capable of in vivo remodeling and probable growth of new heart muscle [4Yanagawa R. Rao V. Yau T.M. Cusimano R.J. Potential myocardial regeneration with CorMatrix ECM: a case report.J Thorac Cardiovasc Surg. 2014; 147: e41-e43Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar]. It may well be that multiple ECM products will be required and that one design does not fit all needs. Regenerative medicine is the future for many cardiovascular diseases. The negative findings in this review add to the other small series of worrisome anecdotes. The discrepancy between favorable opinions by other surgeons who use CorMatrix enthusiastically contributes to the confusion as to what its role is and should be. More comprehensive follow-up or prospective study is required to determine its place in clinical practice. Tissue Reaction to Porcine Intestinal Submucosa (CorMatrix) Implants in Pediatric Cardiac Patients: A Single-Center ExperienceThe Annals of Thoracic SurgeryVol. 99Issue 4PreviewDecellularized porcine small intestine submucosa (CorMatrix, Atlanta, GA) patches have been used in the repair of congenital heart malformations. Tissue reaction to the material may create hemodynamic dysfunction and necessitate explantation. We reviewed our series of congenital cardiac patients who had a reoperation after the implantation of CorMatrix patches. Full-Text PDF