Failure of the Hemashield extension in right ventricle-to-pulmonary artery conduits

• Published in: The Annals of thoracic surgery Vol. 56; no. 2; pp. 277 - 281
• Main Authors: Kobayashi, Junjiro, Backer, Carl L., Zales, Vincent R., Crawford, Susan E., Muster, Alexander J., Mavroudis, Constantine
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY Elsevier Inc 01.08.1993; Elsevier Science
• Subjects: Adolescent; Aorta - transplantation; Biological and medical sciences; Blood Vessel Prosthesis; Child; Child, Preschool; Echocardiography, Doppler; Foreign-Body Reaction - pathology; Graft Occlusion, Vascular; Heart Defects, Congenital - diagnostic imaging; Heart Defects, Congenital - surgery; Heart Ventricles - surgery; Humans; Infant; Infant, Newborn; Medical sciences; Methods; Pulmonary Artery - surgery; Pulmonary Artery - transplantation; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the heart; Human; Prosthesis; Right ventricle; Homograft; Cardiovascular disease; Congenital disease; Pulmonary artery; Graft failure; Treatment; Heart disease; Collagen; Surgery; Fallot tetralogy; Complication; Child; Truncus arteriosus
• ISSN: 0003-4975; 1552-6259
• DOI: 10.1016/0003-4975(93)91159-K

Between 1989 and 1991, 17 childien underwent 18 right ventricle-to-pulmonary artery conduit placement operations using a composite of an aortic or pulmonary valved homograft and a Hemashield extension to the ventricle. Hemashield is a collagen-coated knitted Dacron graft with excellent compliance and hemostatic properties. Diagnoses included tetralogy of Fallot with pulmonary atresia (7), truncus arteriosus (6), and complex transposition of the great arteries (4). Mean age at conduit placement was 4.9 ± 4.2 years, and all patients survived. At a mean follow-up of 14 ± 4 months, postoperative Doppler echocardiographic gradients between the ventricle and pulmonary artery ranged from less than 20 to 60 mm Hg. At cardiac catheterization 13 ± 3 months postoperatively (6 patients), the systolic pressure gradient across the conduits ranged from 14 to 90 mm Hg (mean gradient, 59 ± 29 mm Hg). Conduit obstruction, when present, was demonstrated angiographically to be in the Hemashield portion and led to early conduit replacement six times in 5 patients (33% of operations) within 10 to 18 months (mean time, 14 months) after insertion of the original conduit. Pathologic examination of the explanted conduits revealed the obstruction to be a thick neointimal peel that was impossible to separate from the Hemashield graft. Failure of the Hemashield as an extension for ventricle-to-pulmonary artery conduits secondary to accelerated neointimal formation has led us to abandon its use in clinical practice.