The Layer Where the Coronary Arterial "Endarterectomy" Specimen Separates from the Underlying Artery.

Described herein is a patient who had a coronary endarterectomy at the time of coronary artery bypass grafting. Histologic study of cross-sections of the endarterectomy specimen disclosed that the layer of separation of the endarterectomy specimen from the underlying native artery was in the media. This layer or plane of excision is virtually always the media irrespective of the artery having the endarterectomy. The procedure might better be called "endomediaectomy?"

Segmental Arterial Mediolysis with Preceding Symptoms Resembling Viral Infection Hampers the Differentiation from Polyarteritis Nodosa.

A middle-aged man presented with a fever, arthralgia, gastrointestinal symptoms, headache, and rash. After two weeks, the patient suddenly complained of severe abdominal pain, and computed tomography revealed aneurysms in the hepatic and splenic arteries, which increased in size progressively. Given the elevated levels of inflammatory markers and orchitis, polyarteritis nodosa (PN) was initially suspected. Catheter embolization for the ruptured hepatic aneurysm and splenectomy for the large splenic ones were performed, and the pathological finding was consistent with segmental arterial mediolysis (SAM). Changes in inflammatory marker levels and aneurysmal size are also informative to differentiate SAM from PN.

Down-regulation of vascular GLP-1 receptor expression in human subjects with obesity.

It has been thought that incretin signaling prevents arteriosclerosis, and very recently anti-arteriosclerotic effects through GLP-1 receptor were finally demonstrated in clinical human study. The purpose of this study was to investigate how vascular GLP-1 receptor expression is influenced in human subjects. First, we evaluated GLP-1 receptor expression in human arteries in immunostaining. Next, we separated the artery into the intima and media, and evaluated gene expression levels of various factors. We divided the subjects into obesity and non-obesity group and compared their expression levels between them. Finally, we evaluated which factors determine vascular GLP-1 receptor expression. GLP-1 receptor expression in intima and media was lower in obesity group compared to non-obesity group which was correlated with the alteration of TCF7L2 expression. Multiple regression analyses showed that BMI was an independent determining factor for GLP-1 receptor expression in the intima and media. Furthermore, using small interfering RNA method and TCF7L2-EGFP adenovirus, we showed that TCF7L2 was involved in GLP-1 receptor expression in human vascular cells. Taken together, vascular GLP-1 receptor and TCF7L2 expression was significantly down-regulated in human subjects with obesity. In addition, it is likely that TCF7L2 functions as a modulator of vascular GLP-1 receptor expression.

[Hemothorax due to Idiopathic Rupture of Pulmonary Artery with Defect of Tunica Media].

A 47-years-old man with hemodynamic shock was refered to our hospital by an ambulance. Chest computed tomography(CT)showed left hemothorax and the extravasation of contrast media in his left lung. Emergency operation was done. A lot of intrathoracic hematoma and pulsating bleeding from the lung was found, and lingular segmentectomy was performed. Pathologically, the rupture of pulmonary artery of 2.2 mm in diameter was found without the finding of imflammation nor degeneration due to any basal diseases. Around the lesion, some artery of 0.3~3.0 mm in diameter showed defect of tunica media. This vascular anomaly was considered to lead his hemothorax.

Percutaneous Treatment of Multiple Recurrent Thromboembolization from a Descending Thoracic Aortic Intimal Sarcoma.

Aortic intimal sarcomas are rare tumors that may result in distal embolic ischemia. Here, we present a patient who presented with crescendo lower extremity and mesenteric ischemic events from malignant macroembolism. Management with percutaneous pharmacomechanical thromboembolectomy enabled restoration of distal perfusion and minimally invasive collection of tumor sample to confirm the suspected diagnosis of aortic sarcoma. The patient underwent definitive aortectomy and reconstruction and is recovering well.

Spontaneous rupture of an isolated iliac artery dissection in a young man because of cystic medial degeneration Erdheim-Gsell.

BACKGROUND: Rupture of isolated iliac artery dissections is a life-threatening event and has not been associated with cystic medial degeneration (CMD) Erdheim-Gsell. METHODS: A young man presented to our emergency unit in a critical hemodynamic condition. Computed tomography scan feigned the rupture of an internal iliac artery. RESULTS: Surprisingly, we found a ruptured dissection of the common iliac artery during open surgery. Reconstruction was done by Dacron graft interposition between common and internal iliac artery and external iliac artery implantation into the graft. Histology revealed CMD. CONCLUSIONS: Spontaneous iliac artery dissection and rupture can be caused by CMD and requires immediate surgical intervention.

Maximum preservation of the media in carotid endarterectomy.

Carotid endarterectomy (CEA) is intended to remove atheromatous plaque by dissecting a plane between the intima and the media (circular medial fibers), but this may not be the optimal dissection plane. The present technique is based on identifying the plane that divides the media from the plaque, so preserving the media on the adventitia as much as possible. This plane is more difficult to find and follow than the easy-to-dissect plane usually located between the media and the adventitia, because the plaque invades the media and so the dividing plane is located within the media. In this prospective observational study, CEA was performed in 22 patients to histologically examine the excised plaques and small samples of the whole arterial wall, and evaluate the clinical outcomes. Plaque had invaded the luminal part of the media in the whole arterial wall sample of 80% of cases. Thin medial layers covering > 80% of the surface of the plaque were found in 16 of 22 plaques (73%). Some atheromatous component was sometimes left in the preserved media, rather than completely removed with the media. No morbidity or mortality had occurred by discharge. Only 1 small ipsilateral infarction (4.5%) and no restenosis of greater than 50% were detected during the mean follow-up period of 7 years. Since the plaque usually invades the media, the optimum dissection plane may be located within the media, dividing it into two layers. The presence of some remnant atheromatous components in the preserved media was not associated with surgical complications or restenosis.

Autologous adventitial overlay method reinforces anastomoses in aortic surgery.

In this study, we present an inexpensive and effective method for providing a secure and hemostatic anastomosis using autologous adventitia obtained from a dissected or aneurysmal wall. The resected aortic wall is separated between the adventitia and media, and a soft, 2 × 10-cm adventitial strip is overlaid to cover the anastomotic margin. A graft is sutured to the aortic stump. This autologous adventitial overlay method can inexpensively and strongly reinforce the anastomosis during aortic surgery for dissection or aneurysm and will contribute to anastomotic hemostasis and long-term stability.

Microvasculature of carotid atheromatous plaques: hemorrhagic plaques have dense microvessels with fenestrations to the arterial lumen.

BACKGROUND: Microvessels in atheromatous plaques are well known to play a role in plaque vulnerability associated with intraplaque hemorrhage, but their architecture remains unclear. The morphometry of the microvasculature and hemorrhage of human carotid atheromatous plaques (CAPs) were evaluated, and 3-dimensional (3D) reconstruction of the microvessels was performed. METHODS: CAPs were obtained by endarterectomy in 42 patients. The specimens were analyzed using light microscopy. Plaque hemorrhage was defined as an area-containing red blood cells (>1 mm2). To determine the histopathologic features of plaque hemorrhage, the plaque area was divided into 4 regions: cap, shoulder, lipid/necrotic core, and media. Then, the density of microvessels and macrophages in each region was quantified. Two representative lesions with either hemorrhagic or nonhemorrhagic plaque were cut into 90 serial sections. The sections were double stained with anti-CD34 and anti-α smooth muscle actin antibodies, scanned using a digital microscope, and reconstructed using TRI-SRF2 software. RESULTS: The hemorrhagic plaques showed a higher density of microvessels than nonhemorrhagic plaques in the shoulder, cap, and lipid/necrotic core (P=.03, .009, and .001, respectively), and there was positive correlations between its density and macrophages in each regions (P<.001, .001, and .019, respectively). 3D imaging also revealed dense microvessels with a network structure in the cap and shoulder regions of hemorrhagic plaques, and some of the vessels were fenestrated to the arterial lumen. CONCLUSIONS: The microvasculature of plaques with intraplaque hemorrhage was dense, some of which fenestrated to the arterial lumen. The pathologic 3D imaging revealed precise architecture of microvasculature of plaques.

Comparison of aortic media changes in patients with bicuspid aortic valve stenosis versus bicuspid valve insufficiency and proximal aortic aneurysm.

OBJECTIVES: The aim of this study was to evaluate aortic media changes in bicuspid aortic valve (BAV) patients who underwent aortic valve replacement (AVR) and simultaneous replacement of the proximal aorta for BAV stenosis vs BAV insufficiency. METHODS: Review of our institutional BAV database identified a subgroup of 79 consecutive BAV patients (mean age 52.3 ± 13 years, 81% men) with BAV stenosis or insufficiency and concomitant proximal aortic dilatation of ≥50 mm who underwent AVR and simultaneous replacement of proximal aorta from 1995 through 2005. All cases of BAV disease and concomitant ascending aortic dilatation of 40-50 mm underwent isolated AVR and therefore were excluded from this analysis. Proximal aortic media elastic fibre loss (EFL) was assessed (graded 0 to 3+) and compared between patients with BAV stenosis (Group I, n = 44) vs BAV insufficiency (Group II, n = 35). Follow-up (690 patient-years) was 100% complete and 9.1 ± 4.6 years long. RESULTS: Mean aortic media EFL was 1.3 ± 0.7 in Group I vs 2.5 ± 0.8 in Group II (P = 0.03). Moderate/severe EFL (i.e. defined as grade 2+/3+) was found in 13 patients (29%) in Group I vs 28 patients (80%) in Group II (P < 0.001). Logistic regression identified BAV insufficiency as the strongest predictor of moderate/severe EFL (OR 9.3; 95% CI 3.2-29.8, P < 0.001). Valve-related event-free survival was 64 ± 8% in Group I vs 93% ± 5% in Group II at 10 years postoperatively (P = 0.05). A total of 4 patients (5%, 3 from Group I and 1 from Group II) underwent redo aortic root surgery for prosthetic valve endocarditis during follow-up. CONCLUSIONS: Patients with BAV insufficiency and a proximal aorta of ≥50 mm have a significantly higher rate of moderate/severe EFL as compared to their counterparts with BAV stenosis.

Early histological changes in the porcine aortic media after thoracic stent-graft implantation.

PURPOSE: To describe the histological findings in the aortic wall 5 days after thoracic endovascular aortic repair (TEVAR) in a porcine model. METHODS: Two overlapping stent-grafts were implanted in each of 6 juvenile pigs, covering the entire descending thoracic aorta (DTA). On the 5(th) postoperative day, tissue samples were taken from the DTA in each animal. Medial thickness and medial necrosis were quantified and compared to measurements from the aortas of 6 control animals. RESULTS: Significant medial thinning was observed in stent-covered regions in the test animals. At the proximal landing zone, aortic wall thickness changed from 1387±68 to 782±74 µm within the covered aortic segment (p = 0.028); at the distal landing site, the wall thickness was 365±67 µm within the stent and 501±57 µm distally (p = 0.028). In the overlap zone, the aortic wall measured 524±122 vs. 1053±77 µm in native controls (p = 0.004). Aortic thickness proximal to the graft did not differ from the proximal region of native aortas (1468±96 vs. 1513±80 µm, p = 0.423), but the aorta was significantly thinner distal to the stent (707±38 vs. 815±52 µm, p = 0.004). Laminar necrosis constituted 38%±7% of the media in the proximal landing zone, 54%±4% in the overlap zone, and 46%±13% in the distal landing zone. CONCLUSION: In this porcine model, significant medial thinning and necrosis of the stented aorta was observed. The findings suggest an early phase of vulnerability of the aortic wall, before scarring and adaptive changes have strengthened the residual aorta.

Effects of removal of the adventitia of the descending aorta and structural alterations in the tunica media in pigs.

OBJECTIVE: To investigate the effects of removal of the adventitia on the tunica media in a pig model. METHODS: The experiment was performed in eight pigs. The adventitia of the descending aorta was removed. Following euthanasia, at two, four, six and eight weeks, the aortic segment was removed. Next, slices of the aorta were stained with hematoxylin and eosin (HE) and Weigert-Van Gieson. RESULTS: After two weeks there was a slight cellular breakdown in the outer third of the media. After four weeks structural breakdown of elastic fibers was observed in the outer two thirds of the same layer. In six weeks, several areas of necrosis and almost complete disruption of elastic fibers were identified. Finally, after eight weeks, there was fibrosis of the entire wall with disruption of the internal elastic lamina. CONCLUSION: The removal of the adventitia leads to degeneration of the media, determining loss of the normal structure of the aortic wall that is variable in its location, intensity and shape, depending on the length and duration of the ischemic insult.

Efeitos da remoção da túnica adventícia da aorta descendente em suínos / Effects of removal of the adventitia of the descending aorta and structural alterations in the tunica media in pigs

OBJETIVO: Investigar os efeitos da remoção da adventícia da aorta em suínos. MÉTODOS: O experimento foi realizado com oito suínos. Removeu-se a camada adventícia da aorta descendente. Após a eutanásia com duas, quatro, seis e oito semanas, o segmento aórtico era removido. Após, eram feitos cortes histológicos com a coloração de hematoxilina e eosina (HE) e pelo método de Weigert - Van Gieson. RESULTADOS: Após duas semanas identificou-se um leve desarranjo do terço externo da túnica média. Nos animais sacrificados após quatro semanas observou-se um desarranjo estrutural dos terços externos da túnica média. Após seis semanas observou-se necrose da parede aórtica. Finalmente, após oito semanas além da fibrose da parede aórtica identificou-se a destruição da lâmina elástica interna. CONCLUSÃO: A remoção da adventícia da aorta em suínos levou à alterações degenerativas da média, determinando perda da estrutura da parede aórtica que é variável em sua localização, intensidade e forma, dependendo do tempo a partir do qual se estabeleceu a lesão isquêmica.

OBJECTIVE: To investigate the effects of removal of the adventitia on the tunica media in a pig model. METHODS: The experiment was performed in eight pigs. The adventitia of the descending aorta was removed. Following euthanasia, at two, four, six and eight weeks, the aortic segment was removed. Next, slices of the aorta were stained with hematoxylin and eosin (HE) and Weigert - Van Gieson. RESULTS: After two weeks there was a slight cellular breakdown in the outer third of the media. After four weeks structural breakdown of elastic fibers was observed in the outer two thirds of the same layer. In six weeks, several areas of necrosis and almost complete disruption of elastic fibers were identified. Finally, after eight weeks, there was fibrosis of the entire wall with disruption of the internal elastic lamina. CONCLUSION: The removal of the adventitia leads to degeneration of the media, determining loss of the normal structure of the aortic wall that is variable in its location, intensity and shape, depending on the length and duration of the ischemic insult.

Clinical significance of portal-superior mesenteric vein resection in pancreatoduodenectomy for pancreatic head cancer.

OBJECTIVES: The purpose of this study was to determine the significance of portal vein-superior mesenteric vein (PV-SMV) invasion on survival in patients who underwent margin-negative pancreatoduodenectomy (PD) with PV-SMV resection for pancreatic adenocarcinoma. METHODS: We retrospectively reviewed the records of 60 patients who underwent margin-negative PD with or without PV-SMV resection for pancreatic adenocarcinoma between August 2001 and December 2007. The depth of vessel invasion was investigated and was categorized into 3 groups: tunica adventitia, media, and intima. Clinicopathologic factors and survival were analyzed. RESULTS: Portal vein-superior mesenteric vein resection was performed on 19 patients, but only 15 patients (78.9%) had histologically true invasion and showed poorer survival (median survival, 14 vs 9 months; P < 0.05). Univariate analysis revealed that poorly differentiated tumor, lymphatic invasion, endovascular invasion, PV-SMV invasion, and invasion into the intima of PV-SMV were statistically significant. Poorly differentiated tumor and invasion into the intima of PV-SMV were significant in multivariate analysis. CONCLUSIONS: Aggressive surgical resection should be attempted in cases with suspected PV-SMV invasion because 21.1% of patients had no true invasion and showed better survival than those with true invasion. However, invasion into the tunica intima may be a poor prognostic factor for survival even after margin-negative PD for pancreatic adenocarcinoma.

Alterations in the medial layer of the main pulmonary artery in a patient with longstanding Fontan circulation.

In the past, pulmonary arterial (PA) structure has been extensively investigated with the aim of providing an insight into operative indication for patients with congenital heart disease (CHD). Although PA histological analysis is applied less frequently in the current era, demographic changes of CHD patients require a refocussing of attention. With an exponential increase in the number of adult CHD patients, it is important to realise how structural changes evolve long after previous procedures as a certain proportion of such cases necessitate surgical or interventional manipulation on their PAs. Herein we present our findings on main PA tissues obtained from a 35-year-old woman who had been palliated with a classic Fontan operation 23 years earlier. Immunohistological analysis showed severe alterations, especially in the medial layer; not only attenuation of muscular component but also disarray and fragmentation of elastic fibres were remarkable, which should represent the adaptive response to longstanding diminished lung perfusion. To our knowledge, these observations have not been well described in the literature, presumably because previous studies were conducted primarily with respect to 'increased' pulmonary flow, and hence little is known regarding structural alterations in response to 'decreased' perfusion. Our findings are provided with a review of the literature.

Modification of the descending thoracic aortic anastomotic site using biodegradable felt: study in a canine model with or without basic fibroblast growth factor.

OBJECTIVES: We investigated the outcomes of reinforcing anastomotic sites using (1) nonbiodegradable polytetrafluoroethylene (PTFE) felt, (2) biodegradable polyglycolic acid (PGA) felt, and (3) PGA felt with basic fibroblast growth factor (bFGF) in a canine descending thoracic aortic replacement model. METHODS: Thirty-seven beagles underwent descending thoracic aorta replacement using a prosthetic graft with one of the above-mentioned reinforcements or no reinforcement for controls. Histologic evaluations were carried out 1 month and 3 months after surgery. The biomechanical strength of the anastomosis was assessed along the longitudinal axis of the aortic segments using a tensile tester. Local compliance at the anastomotic site was also evaluated in the circumferential direction. RESULTS: The media was significantly thinner in the PTFE group than in the control group (65.8% +/- 5.1% vs 95.0% +/- 9.3% of normal thickness; P < .05). Relative to the control group, the adventitial layer was significantly thinner in the PTFE group (42.3% +/- 8.2% of control; P < .05) but significantly thicker in the PGA and the PGA + bFGF groups (117.2% +/- 11.3% and 134.1% +/- 14.2% of control, respectively; P < .05). There were more vessels in the adventitial layer in the PGA + bFGF group than in the control, PTFE, and PGA groups (29.2 +/- 2.1/mm(2) vs 13.8 +/- 0.8, 5.4 +/- 0.7, 17.0 +/- 1.3/mm(2), respectively; P < .01). There were no significant differences between the four groups in the failure force at anastomotic sites. Local compliance at the anastomotic site was higher in the PGA group than that in the PTFE group (11.6 +/- 1.6 10(-6) m(2)/N vs 5.6 +/- 1.9 10(-6) m(2)/N; P < .05). CONCLUSION: Reinforcement of the experimental aortic wall with PTFE felt resulted in thinning of the media and adventitia and fewer vessels at the anastomotic site. These histologic changes were not observed when biodegradable felt was used. The bFGF failed to augment the modification of the aortic wall with the exception of increased adventitial vessel number. Biomechanical strength of the anastomosis along the longitudinal axis was comparable in all four groups; however, local vascular compliance was better in the biodegradable PGA felt group.

Spontaneous left main coronary artery dissection, possibly due to cystic medial necrosis found in the internal mammary arteries.

A 55-year-old male without previous medical history developed chest pain. Coronary catheterization showed left main coronary dissection. Coronary artery bypass grafting was performed using bilateral internal mammary arteries, which were very fragile. The specimens of the internal mammary arteries sent for pathology showed cystic medial necrosis.