PURPOSE: This study was designed to investigate the distribution of vasa vasorum in walls of failed aorto-coronary venous grafts. METHODS: Fifty-one diseased venous grafts harvested from 39 patients underwent qualitative histological evaluation. The morphology of the grade of the pathological changes and the extent of the vascularisation were examined, and related to the length of the interval between the primary surgery and the explantation. The obtained results were placed into five groups, substantially differing one from the other in morphology and vascularisation. RESULTS: The intervals between grafts implantation and explantation ranged from 1 day to 35 years. The onset of arterialization of the graft media was observed on average at 1 month after bypass implantation. During this same time period massive intimal hyperplasia and atherosclerosis occurred. Vasa vasorum proliferation from the adventitia to the outer layers of the media was first apparent between 7 and 24 months after implantation. Proliferation of the vasa vasorum throughout the entire atherosclerotic media and hyperplastic intima continued for a much longer time interval. CONCLUSION: No correlation between neoangiogenesis and age, sex or type of bypassed coronary branch was proven. Regarding the given findings, the authors believe that changes in hemodynamic conditions and endothelial trauma are primarily responsible for the development of graft disease and that vasa vasorum proliferation is only a secondary reaction to the structural changes of the graft wall. To what extent the frequently present pre-existing intimal hyperplasia of venous bypass grafts play in the development of graft disease remains questionable.

• Klíčová slova
• Failed aorto-coronary venous bypass grafts, Histology, Saphenous vein, Vasa vasorum,
• MeSH
• aorta patologie   chirurgie   MeSH
• časové faktory MeSH
• koronární bypass metody   MeSH
• koronární nemoc patologie   chirurgie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• neúspěšná terapie MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• vasa vasorum patologie   MeSH
• vény patologie   transplantace   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Pulmonary artery banding (PAB) is used as a surgical palliation to reduce excessive pulmonary blood flow caused by congenital heart defects. Due to the lack of microscopic studies dealing with the tissue remodeling caused by contemporary PAB materials, this study aimed to assess histologic changes associated with PAB surgery by analyzing local tissue reaction to the presence of Gore-Tex strips fixed around the pulmonary artery. Gore-Tex strips were used for PAB in a growing porcine model. After 5 weeks, histologic samples with PAB (n = 5) were compared with healthy pulmonary arterial segments distal to the PAB or from a sham-treated animal (n = 1). Stereology was used to quantify the density of the vasa vasorum and the area fraction of elastin, smooth muscle actin, macrophages, and nervi vasorum within the pulmonary arterial wall. The null hypothesis stated that samples did not differ histopathologically from adjacent vascular segments or sham-treated samples. The PAB samples had a greater area fraction of macrophages, a lower amount of nervi vasorum, and a tendency toward decreased smooth muscle content compared with samples that had no PAB strips. There was no destruction of elastic membranes, no medionecrosis, no pronounced inflammatory infiltration or foreign body reaction, and no vasa vasorum deficiency after the PAB. All the histopathologic changes were limited to the banded vascular segment and did not affect distal parts of the pulmonary artery. The study results show the tissue reaction of palliative PAB and suggest that Gore-Tex strips used contemporarily for PAB do not cause severe local histologic damage to the banded segment of the pulmonary arterial wall after 5 weeks in a porcine PAB model.

• MeSH
• arteria pulmonalis patologie   chirurgie   MeSH
• hemodynamika MeSH
• ligace MeSH
• modely nemocí na zvířatech MeSH
• následné studie MeSH
• prasata MeSH
• svaly hladké cévní patologie   MeSH
• vrozené srdeční vady patologie   chirurgie   MeSH
• výkony cévní chirurgie metody   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH