Search PubMed⌕ Search

Biomedical subjects

R Limet

Publications and source records attributed to R Limet.

At least 199 records · Page 11Linked to original sources

[Role of carotid surgery in the prevention of cerebral infarction].

A significant part of transient or permanent cerebral ischemic attacks (CIA) are due to arterio-arterial emboli issued from carotid plaques. Surgery for carotid disobstruction aims to take out emboligenic plaques by endarterectomy (associated to angioplasty or not). The adversaries of surgical treatment sustain two main assertions: 1. carotid stenoses are not very dangerous, because the definitive thromboses they create are easily compensated by the development of collaterals, so that the risk for stroke is low. 2. this low and late risk of spontaneous carotid thrombosis is not greater than the immediate one following carotid surgery. Those objections have been encountered in randomized North American studies (Nascet & Veterans) that have been published in 1991 and 1993. They show the usefulness of correctly done surgical correction as well as for symptomatic as asymptomatic stenoses. So do we it, presenting the results of our series (2.282 procedures in 1.868 patients). The results of our series show a low combined morbidity-mortality rate (1.7%), and a yearly stroke of 1.4%.

Adult↗

[Rupture of a superficial femoral aneurysm in the context of neurofibromatosis. Report of a case].

The authors observed the spontaneous rupture of a dysplastic superficial femoral artery in a 47 years old patient with Von Recklinghausen disease. The patient presents a gigantism of his right lower limb. On angiography, the femoropopliteal axis is polyaneurysmal and there is evidence of rupture at mid-thigh. The diseased artery is excluded by interposition of a dacron prosthesis, with reimplantation of the deep femoral artery. Histology shows fibrohyalin thickening of the intima. Dysplasia of large limb arteries is excessively rare in Von Recklinghausen disease.

Aneurysm, Ruptured↗

Misdiagnosed malignancy in transplanted organs.

The case reports of three patients who received cancer-bearing organs at this institution are presented. A fourth recipient, who was to be transplanted with a cancerous kidney, was spared this disastrous complication. The relevant data regarding the donors is also alluded to, with special reference to the type and site of the primary malignancy. Following these case reports, the implications of these issues, their possible prevention, and further management are discussed.

Adult↗

Modifications of the extracellular matrix of aneurysmal abdominal aortas as a function of their size.

Collagen and elastin are the main extracellular matrix proteins providing the aortic wall with adequate mechanical properties and resistance for proper function. Our study aimed at investigating the relationship between the elastin concentration of the wall of normal and aneurysmal abdominal aortas (AAA), the collagen concentration, and its extractability, as a function of their size. Infrarenal aortas were collected from 30 patients undergoing operative repair of abdominal aortic aneurysm. Age-matched control samples were obtained from eight autopsies of individuals without vascular disease. Samples were divided into five groups according to the aortic diameter: control group (group N, n = 8); < 50 mm (group I, n = 6; between 50-75 mm (group II, n = 10); > 75 mm (group III, n = 7); and ruptured (group IV, n = 7). The collagen concentration in samples from group I was similar to the controls. An increased collagen concentration was observed in group II and remained at the same level in the largest and ruptured aneurysms. Extractability of collagen was found to be increased in group III and was even higher in group IV. A highly significant reduction in elastin concentration was observed in group I and there was progressive reduction with increasing diameter and rupture. A significant correlation could be established between aortic diameter, increased collagen extractability and decreased elastin content.

Aged↗

In vivo free radical production after cross-clamping and reperfusion of the renal artery in the rabbit.

Postischaemic reperfusion injury is often attributed to the generation of oxygenated free radicals which may subsequently promote lipid peroxidation in cell membranes. Electron paramagnetic resonance spectroscopy in association with the spin trap molecule alpha-phenyl-N-tert-butyl-nitrone allowed direct confirmation of lipid free radical production after renal ischaemia-reperfusion in an in vivo rabbit model. A 60-min period of ischaemia followed by reperfusion caused free radical production twofold greater than after 15 min of ischaemia. Glutathione and alpha-tocopherol have been measured in renal tissue, as indirect markers of lipid peroxidation. After 15 min of ischaemia followed by 10 min of reperfusion, the mean(s.e.m.) glutathione content of the ischaemic kidney was slightly but significantly reduced by 11.9(2.5)% (P < 0.003). The content of alpha-tocopherol was unchanged. However, 10 min of reperfusion following 60 min of ischaemia led to significant decrease in mean(s.e.m.) content of both glutathione (30.4(3.7)%) (2.23(0.2) versus 3.14(0.18) mumol/g wet tissue, P < 0.001) and alpha-tocopherol (46.1(7.8)%) (0.57(0.10) versus 1.09(0.14) micrograms/g wet tissue, P < 0.001) when compared to the control kidney. Under these experimental conditions, desferrioxamine (15 mg/kg administered intravenously before inducing ischaemia), a drug known to limit free radical production, significantly limited the decrease of alpha-tocopherol to 20.8(6.4)% (0.83(0.08) versus 1.05(0.04) micrograms/g wet tissue, P < 0.05), but did not prevent glutathione consumption in the reperfused kidney.

Animals↗

[Is age a limiting factor for carotid surgery?].

To evaluate the role of carotid surgery in elderly patients 75 years and older, we reviewed 912 carotid endarterectomies performed on 806 patients between 1987 and 1990. There were 151 patients (19% of the whole series) aged 75 years and older (160 endarterectomies, group A), including 29 octogenarians, vs 655 patients under 75 years of age (group B). There were more women in the elderly age group (44%) than in the younger one (38%). Symptoms, risk factors, operative outcome and follow up data of the two groups were compared. The risk profile was similar for the two age groups, with exception for coronary heart disease, less frequent in the older patient group (25% had previous infarction vs 44%). Indication for carotid endarterectomy was different in the two age groups: 41% of group A underwent prophylactic thrombendarterectomy for high degree stenosis, while only 30% of group B had asymptomatic carotid disease. In group A, 6% of the patients had carotid endarterectomy after recovering from a mild stroke, vs 2% in group B. Angiography revealed bilateral carotid disease in 59% of the group A patients (including 15% with contralateral occlusion) vs 40% in group B. Operative mortality was 1.5% for the younger age group vs 2.5% for the older age group. The cause of death was cardiac in 60%. A follow up is available for all patients who benefited carotid endarterectomy since 1976, including 180 patients aged 75 years or older.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

[Mediastinitis: diagnosis, risk factors and treatment].

The authors review the literature concerning post-sternotomy mediastinitis. The incidence, mortality, diagnosis and risk factors are discussed, but above all, the various treatments are reviewed and compared with respect to their advantages and risks, their respective usefulness and results, in order to define a reasonable way of management of this highly pejorative surgical complication. Open technique, closed irrigation and surgical flaps of omentum, pectoralis major and rectus abdominis are successively considered.

Anti-Bacterial Agents↗

Spontaneous rupture of the iliac vein.

A spontaneous rupture of the left iliac vein is described. A 2 cm tear on the anterior surface of the left iliac vein was discovered at emergency laparotomy on a patient who was suspected of having a huge intraabdominal hemorrhage. Prodromal symptoms, cause, and treatment are discussed. The nine previously reported cases are reviewed. This case represents the seventh successful repair of an idiopathic rupture of an iliac vein.

Emergencies↗

Mycotic aneurysm of the upper abdominal aorta ruptured into the stomach.

We report a case of primary aortogastric fistula with erosion of a mycotic aneurysm of the upper abdominal aorta into the stomach. The patient was successfully operated on with an in situ aortoaortic tube graft, incorporating the splanchnic vessels, and direct suture of the gastric erosion.

Aneurysm, Infected↗

Anatomical rationale for use of the latissimus dorsi flap during the cardiomyoplasty operation.

The cardiomyoplasty procedure involves the use of a transformed skeletal muscle to augment cardiac pump function or to substitute for the heart after parietal resection. This study of the intramuscular vascularization of latissimus dorsi was carried out in order to establish the relationship between the dominant thoracodorsal blood supply and the distal supply issued from the intercostal and lumbar arteries. This data is mandatory for the safe manipulation of the muscle flap during cardiomyoplasty. Thirty human latissimus dorsi flaps were carefully studied. We confirmed anatomically as well as angiographically previous macroscopic anatomical reports, as well as the constancy of the neurovascular pedicle. Three principal branching patterns were observed for the thoracodorsal artery. The thoracodorsal artery divides into three main tributaries in 20/30 (67%), and into two tributaries in 10/30 (33%) of the flaps observed. When three tributaries were observed, one of them was a small recurrent artery for the proximal third of the latissimus dorsi (14/20, 70%). Thus the distal vascularization is actually dependent on three principals in 6/30 (20%) and two principals in 24/30 (80%). From these two or three principals emerge several subsequent longitudinal branches (5 to 9) that have a straight course until their distal anastomoses with segmental arterial pedicles issued from intercostal and lumbar arteries. The latter ligation can thus occur without ischemic damage to the medial and distal aspect of the flap. This study emphasizes that, due to macroscopic anatomic features and systematic intramuscular vascular distribution, the latissimus dorsi is probably the most suitable muscle for the purpose of cardiomyoplasty.

Assisted Circulation↗

Aneurysm of the ascending aorta after cardiac transplantation.

We report the case of a 57-year-old female cardiac transplant patient in whom an aneurysm of the recipient side of the ascending aorta developed 1 year after transplantation. Although a mycotic origin was the likely cause, histologic examination diagnosed an atherosclerotic aneurysm.

Aortic Aneurysm↗

Failure of buserelin-induced medical castration to control pulmonary lymphangiomyomatosis in two patients.

Two women, aged 44 and 29 years, respectively, were admitted to the hospital in early 1987 for recurrent pneumothorax, dyspnea and a diffuse reticulonodular pattern evidenced on the chest x-ray film. Lung biopsy confirmed LAM in both patients. Both were treated sequentially with medroxyprogesterone and a LHRH agonist (buserelin) to achieve reversible medical castration. Neither subjective nor objective improvement was noted after 13 and 5 months, respectively, of buserelin therapy (900 micrograms/day, nasal spray) despite an effective suppression of the pituitary-gonadal axis. Medroxyprogesterone also was ineffective. Buserelin thus failed to control pulmonary LAM in these two patients, in spite of effective medical castration.

Adult↗

[Determination of level of expansion and incidence of rupture of abdominal aortic aneurysms].

We studied 114 patients (out of a cohort of 797 consecutive patients admitted with abdominal aortic aneurysm) who were denied any immediate operation because of patient's refusal, high surgical risk, or small transverse diameter as assessed by CT scanning and ultrasonography. All patients not operated on, underwent from two to six repeated examinations during an average follow-up period of 16.8 months (range, 3 to 132). Forty-seven patients (41.2%) were subsequently operated on electively because of marked increase of transverse diameter of the aneurysm (n = 44) or for other reasons (n = 3), with a death rate of 0%. Eighteen other patients underwent emergency operation for leaking or ruptured aneurysms, and there were five deaths. The incidence of rupture was clearly related to the final diameter value, rising from 0% in aneurysms less than 40 mm to 22% in large size aneurysms (> or = 50 mm). Among the 49 patients not operated on, one died of rupture before operation and five of causes unrelated to the disease. Using individual serial measurements, we determined the linear expansion rate of the aneurysm, which proved to be related to initial diameter values: 5.3 mm/year for diameters less than 40 mm (n = 49), 6.9 mm/year in the 40 to 49 mm group (n = 41), and 7.4 mm/year for diameters of 50 mm or more (n = 24). We also fitted an exponential model to the patient data and determined in each case an "exponential" expansion rate expressed in year-1. The overall mean was equal to 0.129 year-1, and individual values were found to be independent of initial diameter size. The superiority of the exponential model over the linear model was shown to be statistically significant. Our study confirms that expansion of aneurysms is related to initial diameter values and shows that the time evolution of the disease process can be adequately described by an exponential model. It also suggests that rupture of aneurysms is not only related to their size but also to their rate of expansion.

Aortic Aneurysm, Abdominal↗