Equine Pericardial Patch Research Articles

New surgical technique for total-defect aortopulmonary window

A new technique is described to repair aortopulmonary window with total defect in an 8-day-old baby. Because we expected the future growth of aorta, we used the anterior wall of the pulmonary artery as a large flap to reconstruct the posterolateral aortic wall. An equine pericardial patch was used to repair the defect in the pulmonary artery. This is a logically effective method for aortic reconstruction in a neonate with a large aortopulmonary septal defect.

Palliative repair of aortic atresia associated with tricuspid atresia and transposition of the great arteries

Successful palliative repair of aortic atresia and hypoplastic aortic arch associated with tricuspid atresia in a neonate is described. The repair consisted of reconstruction of the hypoplastic aortic arch with an equine pericardial patch, division of the patent ductus arteriosus, connection of the pulmonary artery to the aorta, implantation of the proximal part of the ascending aorta into the main pulmonary artery, and anastomosis of a polytetrafluoroethylene graft 5 mm in diameter between the right ventricular outflow tract and the central pulmonary artery, which was transferred anteriorly to the main pulmonary artery.

A new look at pericardial substitutes

The presence of pericardial adhesions may increase morbidity and mortality during reoperation for cardiac disease. Pericardial substitutes (patches) are commercially available, and reportedly they reduce or prevent adhesions. We implanted five (1984 to 1985) newer pericardial substitutes in dogs. A new polytetrafluoroethylene surgical membrane, two types of glutaraldehyde-stabilized bovine pericardium, formaldehyde-preserved bovine pericardium, and glutaraldehyde-stabilized equine pericardial patches were each implanted in six adult dogs (total 30 dogs) with two dogs from each of the five groups killed at 3, 9, and 18 months. At autopsy the condition of each patch was recorded photographically, and specimens were substituted for histologic examination. Adhesions and epicardial reactions were graded as none, minimal, moderate, or severe. None of the materials produced severe pericardial adhesions, and no adhesions were detected in nine dogs. Eleven dogs had no epicardial reaction and only one showed a severe reaction. Adhesions to portions of the suture line required sharp dissection in 11 dogs. If there is concern over the possibility of calcification in heterologous tissue, polytetrafluoroethylene may be chosen. Patch type did not significantly alter patch behavior.

Repeat sternotomy after reconstruction of the pericardial sac with glutaraldehyde-preserved equine pericardium

The risk of repeat sternotomy is higher than that of the initial sternotomy, especially if the pericardial sac was left open at the first intervention. In 200 consecutive patients with a pericardial defect after open heart operations, the pericardium was closed with a glutaraldehyde-preserved equine pericardial patch. Precardiac adhesions at reoperation were assessed in four groups of patients on a scale of 6, ranging from 0 (no adhesions) to 5 (calcified or ossified adhesions). Group I comprised 13 patients in whom the pericardium was left open at the first operation and an equine pericardial patch was implanted at reoperation. Group Ia included the first five Group I patients who underwent reoperation less than 1 year (early reoperation) after the initial procedure. Group Ib included the other eight patients of Group I, who underwent reoperation more than 1 year (late reoperation) after the first procedure. Group II comprised nine patients who were reoperated on after reconstruction of the pericardial sac with a glutaraldehyde-preserved equine pericardial patch. After a mean follow-up of 20.2 months, the incidence of patch-related complications was 1%. Statistical analysis shows less severe adhesions on reoperation in Group II patients (pericardial defect patched) than in Group I patients (pericardial defect left open): mean grade of adhesions 1.6 +/- 0.9 (Group II) versus 3.2 +/- 0.6 (Group I), p less than 0.001. Precardial adhesions with the pericardium left open were similar in patients having early and late reoperations: mean grade of adhesions 3.0 +/- 0.7 (Group Ia) versus 3.4 +/- 0.5 (Group Ib), no significant difference. Therefore, the glutaraldehyde-preserved equine pericardial patch can be considered a suitable material for primary closure of the pericardial sac in patients with inadequate autologous pericardium.

Equine Pericardial Xenograft in Orthotopic Position: Early Results

Glutaraldehyde-preserved pericardium was used to close the pericardial sac after open heart surgery in 100 patients. The indication for implantation of a xenologous pericardial patch was always the lack of autologous pericardium to close the pericardial sac without significant tension. This was mainly due to previous use of an autologous pericardial patch or implant of an extracardiac conduit for the repair of congenital cardiac disease (n = 82) and reoperation after primarily open pericardium (n = 10). In this series with a mean follow-up of 3.1 months (range 1 to 12 months) no infection of the xenologous equine pericardial implant and no mediastinitis occurred. Even in cases of early reoperation (n = 6) for bleeding or tamponade there was no patch infection (implants left in situ). At medium-term reoperation in 3 cases, after a mean interval of 115 days, adhesions between the epicardium and the xenologous equine pericardial patch were graded mean 1 (blunt adhesions) on a scale of six (minimum = 0, maximum = 5). In another series of re-dos for coronary bypass surgery with pericardium primarily left open, the mean grade of adhesions formed in the anterior epicardial space was 2.7 (severe). The histology of explanted equine pericardium showed no new vessels and no in-dwelling organization. Although the follow-up is relatively short, this material appears to offer a valid non-adherent substitute to separate the posterior sternal surface and the cardiac cavities. Its application improves the safety at resternotomy.