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R Limet

Publications and source records attributed to R Limet.

At least 19 recordsLinked to original sources
PubMed2000

Evaluation of autoantibodies against oxidized LDL and antioxidant status in top soccer and basketball players after 4 months of competition.

Antioxidant status and titers of autoantibodies against oxidized low-density lipoproteins (ox-LDL-Ab) were investigated in top soccer (S; n = 21, age 24.6 +/- 4.3 years) and basketball (B; n 3,000 mIU/ml) in ox-LDL-Ab were found in half the players (12S and 4B) with a maximum reaching 6000 mIU/ml (normal range: 200-600 mIU/ml), showing an in vivo LDL oxidation. There was no correlation between ox-LDL-Ab titers and chlolesterol, LDL cholesterol, or antioxidant levels. Nevertheless, plasma vitamin C concentration was lower in athletes having high levels of ox-LDL-Ab when compared with those with normal levels (8.49 +/- 3.14 mirogram/ml vs. 10.39 +/- 2.55 microgram/ml), but this difference was not statistically significant. In conclusion, our data suggest that potential atherogenic and cardiovascular risks as reflected by high titers in ox-LDL-Ab may exist in some top athletes despite a nonaltered antioxidant status.

Adult↗
PubMed2000

Increased aortic compliance maintains left ventricular performance at lower energetic cost.

OBJECTIVE: The aim of this study was to investigate left ventricular contractility and energetic cost of cardiac ejection under conditions of acute increase in aortic compliance. METHODS: In six anaesthetized pigs, ascending aortic compliance was increased by adding a volume chamber in parallel to the ascending aorta. Systemic vascular parameters, including characteristic impedance, peripheral resistance, total vascular compliance, and inertance, were estimated with a four-element windkessel model. Arterial elastance was derived from these parameters. Left ventricular systolic function was assessed by end-systolic pressure-volume relationship (end-systolic elastance), and stroke work. Pressure-volume area was used as a measure of myocardial oxygen consumption. Heart rate remained constant during the experimentation. RESULTS: Adding the aortic volume chamber significantly increased vascular compliance from 0. 95+/-0.08 to 1.17+/-0.06 ml/mmHg (P<0.01), while inductance, characteristic impedance, peripheral resistance, and arterial elastance remained statistically at basal values, respectively 0. 0020+/-0.0003 mmHg.s(2)/ml, 0.105+/-0.009 mmHg.s/ml, 1.27+/-0.12 mmHg.s/ml, and 2.43+/-0.21 mmHg/ml. During the same interval, stroke work and pressure-volume area decreased respectively from 2700+/-242 to 2256+/-75 mmHg.ml (P<0.01), and from 3806+/-427 to 3179+/-167 mmHg.ml (P<0.01). Stroke work and pressure-volume area decreased at matched end-diastolic volumes. In contrast, end-systolic elastance, ejection fraction, and stroke volume remained statistically unchanged, respectively at 2.29+/-0.14 mmHg/ml, 48.1+/-2.1 %, and 32. 4+/-1.7 ml. CONCLUSIONS: These data suggest that, when facing an increased aortic compliance, the left ventricle displays unchanged contractility, but the energetic cost of cardiac ejection is significantly decreased. These data may be of clinical importance when choosing an artificial prosthesis for ascending aortic replacement.

Animals↗
PubMed1999

Crossover iliofemoral bypass grafting for treatment of unilateral iliac atherosclerotic disease.

PURPOSE: In patients with unilateral iliac disease, a less invasive procedure than aortobifemoral bypass grafting may be desirable, especially in poor-risk patients or when sexual dysfunction is feared. In these cases, femorofemoral (FF) bypass grafting is often proposed. Compared with FF bypass grafting, iliofemoral (IF) bypass grafting avoids bilateral exposure of the groins, which may reduce the risk of infection. When the primitive iliac artery is occluded from its origin or heavily calcified, one may use the contralateral artery as inflow, after a small retroperitoneal exposure, to perform a crossover iliofemoral (CIF) bypass grafting procedure, through the Retzius space. Our 10-year experience with CIF bypass grafting in a select group of patients was studied. METHODS: Between 1986 and 1996, 36 patients underwent CIF bypass grafting for symptomatic unilateral iliac occlusion or stenosis. All patients were examined by means of Doppler ultrasound scanning and underwent bilateral multiplane angiography. Patients were considered for this procedure when the ipsilateral common iliac artery was occluded from its origin or was diffusely and heavily calcified. The decision to perform a CIF bypass grafting procedure was made when no significant disease of the contralateral common iliac artery was seen, and patients who had features of contralateral iliac disease were excluded. The main outcomes were perioperative mortality and morbidity, long-term primary and secondary patency rates, and limb salvage rate. RESULTS: The study included 31 men and five women, with a mean age of 58.8 years. Indications for bypass grafting were disabling claudication (26 of 36 patients, 72%) and limb-threatening ischemia (10 of 26 patients, 28%). Twelve procedures were performed simultaneously: endarterectomy of the recipient common femoral artery (n = 3), femoropopliteal bypass grafting (n = 4, 11.1%), profundoplasty (n = 4, 11%), and right internal carotid endarterectomy (n = 1). New postoperative erectile dysfunction did not develop in any of the patients. The survival rate was 97.3% at 1 year and 68.5% at 5 years. The primary and secondary patency rates were 94% and 100%, respectively, at 1 year and 76.7% and 95%, respectively, at 5 years. The limb salvage rate was 100% at 1 year and 87% at 3 years. CONCLUSION: The operative mortality associated with CIF is low. The long-term primary and secondary patency rates are satisfactory, and they are lower than those reported for aortobifemoral bypass grafting. This procedure does not preclude a later performance of an aortobifemoral bypass grafting procedure. CIF bypass grafting is not only suitable for poor-risk patients with a limited life expectancy who have the appropriate arterial anatomy, but also may be warranted for young patients in whom erectile dysfunction is feared.

Adult↗
PubMed1999

Femoral anastomotic aneurysms: pathogenic factors, clinical presentations and treatment. A study of 142 cases.

In this study, the files of 112 patients with a total of 142 femoral anastomotic aneurysms were reviewed. Eighty-five patients (76%) were initially operated upon for obstructive aorto-iliac disease, while the remaining 27 (24%) had abdominal aortic aneurysms repaired. The majority of the patients (104/112) were male and their mean age was 64.5 years (range 45-88). Ninety-three per cent of the subjects were smokers prior to the first operation and 43% continued to smoke at the time of their femoral anastomotic aneurysms operation. The mean delay between the initial surgery and the repair of the femoral anastomotic aneurysms was 74.5 months (range 1-228). The diagnosis was made because of a painless pulsatile mass (91/142), acute leg ischaemia (27/142), a painful pulsatile mass (12/142), haemorrhage (10/142), pseudo-post-phlebitic oedema (1/142) and microemboli of the toes (1/142). The operative mortality was 2.7% (3/112) of which two-thirds were patients with infected grafts. Two subgroups were distinguished: 10 patients with an infected femoral anastomotic aneurysm and 12 patients with recurrent femoral anastomotic aneurysms, 11 with a single recurrence and one with a double recurrence. In the infected group, the time to development of anastomotic aneurysm was shorter than for the group with non-infected femoral anastomotic aneurysms (41 versus 74.5 months) and the operative mortality was 20% (2/10). One patient developed a recurrent femoral anastomotic aneurysm and another was lost to follow-up. Two subsequent deaths occurred, which were unrelated to the femoral anastomotic aneurysms. In the group of recurrent femoral anastomotic aneurysms one patient was lost to follow-up and two patients died, but not as a result of recurrent femoral anastomotic aneurysms. A total of 122 cases underwent interposition of a new prosthetic segment between the proximal prosthesis and the distal artery (89 at the common femoral, 21 at the femoral profundis, eight at the superficial femoral and four at an existing femoro-popliteal graft).

Aged↗
PubMed1999

Aortic valve replacement in the octogenarians: perioperative outcome and clinical follow-up.

OBJECTIVES: To determine long-term results of aortic valve replacement (AVR) in patients 80 years old or older, and assess the factors influencing perioperative outcome. METHODS: Data were reviewed on 83 consecutive octogenarians, undergoing aortic valve replacement between 1992 and 1997. There were 66 women and 17 men (mean age: 82.8 years). Fifty-seven patients (69%) were in New York Heart Association (NYHA) class III-IV and six had previous myocardial infarction. Three patients had previous percutaneous aortic valvuloplasty. There were 19 urgent procedures (23%). Coronary artery bypass grafting (CABG) was performed on 21 patients (25%). Possible influence of preoperative and operative variables on early and late mortality was performed with univariate and multivariate statistical analysis, and survival was estimated with the Kaplan-Meier method. RESULTS: Operative mortality was 13% (9% for AVR, 24% for AVR-CABG). Postoperative complications were respiratory failure in 19 patients, atrial fibrillation in 19, hemodialysis in four, myocardial infarction in four and stroke in two patients. Five patients required pacemaker insertion for permanent atrioventricular block. Median hospital stay and intensive care unit stay were 19.8 +/- 12.2 days and 7.9 +/- 3.4 days, respectively. Multivariate predictors of hospital death (P < 0.05) were percutaneous aortic valvuloplasty, NYHA class IV, and urgent procedure. Mean follow-up was 26.5 months. Survival at 1, 2, and 5 years was 98.5 +/- 1.4% (63 patients at risk), 93.4 +/- 3.2% (47 patients at risk), and 78.2 +/- 6.9% (six patients at risk), respectively. Preoperative myocardial infarction and urgent procedure were independent predictors of late death. At most recent follow-up, 91% were angina free and 81% were in class I-II. CONCLUSIONS: Aortic valve replacement in octogenarians can be performed with acceptable mortality. These results stress the importance of early operation on elderly patients with aortic valve disease. Both long-term survival and functional recovery are excellent.

Aged↗
PubMed1999

Typical presentation of intramural aortic haemorrhage (IAH) with evidence of intimal tear at MRI and angiography.

A typical appearance of IAH was evidenced by CT and TEE in a 56-year-old hypertensive female suspected of developping classical acute aortic dissection (AAD). Further examination with MRI and aortography showed unequivocally the presence of an intimal tear in the aortic arch. This coexistence of intimal tear has never been evidenced preoperatively in patients with IAH. This observation demonstrates at the outset that IAH is part of the spectrum of AAD.

Aortic Dissection↗
PubMed1999

[Clinical case of the month. Prolapse due to fibro-elastic degeneration. The aging of the mitral valve].

We report the case of a 73-year-old woman who presents an acute mitral regurgitation secondary to fibro-elastic degenerescence. A mitral valvuloplasty is rapidly performed with complete disappearance of valvular insufficiency and the patient leaves the hospital ten days later. Degenerative mitral regurgitation is commonly seen in elderly patients. This constitutes an excellent indication for mitral valvuloplasty, rather than valve replacement. In our experience, mitral valvuloplasty leads to a complete correction of valvular regurgitation without neither stenosis, nor subvalvular obstruction. Left ventricular function is preserved, as subvalvular apparatus is conserved. This approach allows, in the absence of specific indication, anticoagulation withdrawn two to three months later.

Aged↗
PubMed1999

[Medico-surgical management of childhood cardiopathy: results of the Liège experience].

OBJECTIVE: Evaluation of the results obtained in the management of congenital heart diseases in Liège. MATERIAL AND METHODS: We evaluated the results, the mortality and the morbidity of diagnostic and interventional cardiac catheterization, and of the cardiac surgery in the 123 cardiac children who were referred to us during the three first years of operation of our medico-surgical team. RESULTS: 89 children underwent a catheterization, including 12 therapeutic interventions, whereas 68 were operated. In the two domains, the results are completely comparable with those of the established centers. CONCLUSIONS: The widening of the activity of paediatric cardiology and the creation of an activity of pediatric cardiac surgery in Liège appeared important to us for the quality of management of the cardiac children. This goal could be reached only if our results were comparable with those of the literature. The bet seems to be held. The ultimate objective is to contribute by an adequate policy of management to the quality of life and the health of the cardiac children.

Adolescent↗
PubMed1999

[Anti-platelet agents in peripheral vascular surgery].

Prescription of platelet inhibitors after arterial surgery is common use. The major concern of the vascular surgeon is to maintain patency of arterial reconstructions. Major causes of graft failure or arterial thrombosis are the non-thromboresistant nature of the grafts and of the endarterectomised or balloon-dilated surfaces, restenosis due to intimal hyperplasia and progression of atherosclerotic disease in in- or outflow vessels. Platelet adhesion and intimal injury are the primary causes in both processes of graft thrombosis and intimal hyperplasia. To understand how antiplatelet drugs can interfere with these processes, a brief review of platelet function, and of the main platelet inhibitors (aspirin, dypiridamole, ticlopidine) is given. The pathophysiology of intimal hyperplasia is discussed. From clinical trials of peripheral vascular surgery or percutaneous transluminal angioplasty with or without periprocedural antiplatelet therapy, it appears that platelet inhibitors reduce early failure rate by 50% (thrombosis rate at one year reduced from 40 to 20%). There is also evidence that antiplatelet drugs allow to slow down the progression of the atherosclerotic degenerative process in the outflow vessels and in other vascular territories. For the polyvascular patients with charged passed history, platelet inhibitors reduce the risk of myocardial or cerebral infarction by 30% (secondary prevention). Today, there is a general consensus that antiplatelet drugs, started the day before the procedure, are beneficial for early and late patency of peripheral vascular reconstructions (carotid endarterectomy, infrainguinal bypass grafts or endovascular procedures).

Angioplasty, Balloon↗
PubMed1999

Fibromuscular dysplasia of the internal carotid artery. Personal experience with 13 cases and literature review.

From January 1990 to December 1997, the authors observed 13 cases of fibromuscular dysplasia of the internal carotid artery. Four patients presented transient ischemic attacks, one amaurosis fugax, two suffered from a minor stroke, four had non-focalized ischemic cerebral symptoms and two were asymptomatic. At angiography, all patients showed a typical image of "string of beads". Seven patients were operated on. Six had endoluminal graduated dilatation, with rigid dilators up to 4.5 mm, associated with thrombendarterectomy of the bifurcation in three and to correction of a kink in one case. In one case a venous interposition graft was done to exclude a saccular microaneurysm of the dysplasic internal carotid artery. In another case, backflow was insufficient after endoluminal dilatation, and a long venous patch allowed to restitute a normal vascular lumen. There was neither postoperative mortality nor stroke. Six patients, asymptomatic or with non focalized symptoms, were treated medically. During a mean follow-up of 47 months, only one of the 13 patients developed a transient ischemic attack; the patient had not been operated on and received only medical treatment. Prevalence, etiopathology, diagnosis and management of fibromuscular dysplasia of the internal carotid artery are discussed. Fibromuscular dysplasia is a rare cause of cerebral ischemia. For asymptomatic lesions, a conservative approach seems appropriate. Surgery is only to be considered for symptomatic lesions. Surgical graduated endoluminal dilatation, where necessary combined with standard endarterectomy of the carotid bifurcation, is a safe, efficient and durable operation. Some complex cases of fibromuscular dysplasia may necessitate patch insertion or excision and graft interposition.

Aged↗
PubMed1999

Antiplatelet activity of clopidogrel in coronary artery bypass graft surgery patients.

Clopidogrel is a recently introduced platelet ADP receptor antagonist, belonging to the thienopyridine derivatives, like its analogue ticlopidine. Its potential advantage is to be safer than ticlopidine. At 75 mg/od clopidogrel significantly inhibits platelet aggregation in ambulatory patients with symptomatic atherosclerotic disease and it prevents the recurrence of ischemic events more efficiently than aspirin. Its adequate dose in more acute situations remained to be determined. Therefore, sixty two patients with coronary artery disease were randomly assigned in four groups treated, within 24 h after coronary artery bypass graft, by clopidogrel 50 mg/od, 75 mg/od or 100 mg/od or by ticlopidine 250 mg/bid which was considered as the reference. The tolerance of clopidogrel was fairly good during the whole period of the study. Bleeding time and ex-vivo platelet aggregation induced by ADP 2 microM and 5 microM were performed at day -1, +9 and +28 after surgery. Like ticlopidine, the three dose levels of clopidogrel significantly inhibited ex-vivo platelet activity and prolonged the bleeding time at day 28. However, unlike ticlopidine, the inhibitory effects of clopidogrel were not significant at day 9, especially with 75 mg/od, a dose which was found to significantly protect patients in a chronic situation. Hence, although the clinical outcome for patients included in this limited study was the same in the four groups, these results suggest that the dose regime of clopidogrel should be more extensively investigated during the early period following coronary artery bypass graft, facing an overproduction of young and hyperreactive platelets. By analogy, the dose regime should be also investigated in other situations with an acute risk of arterial thrombotic occlusion.

Adenosine Diphosphate↗
PubMed1999

[Sub-valvular aortic stenosis by a discrete membrane].

We report the case of a 55 year old patient presenting a discrete obstructive sub-aortic membrane. After clinical examination, complete echocardiographic evaluation and cardiac catheterisation, an operative procedure was decided and the sub-aortic membrane was resected. The results were satisfactory but the literature reports risks of re-obstruction of the left ventricular outflow tract. The article points out the importance of an early diagnosis and further stresses the major role played by transoesophageal echocardiography in the evaluation of the patient.

Aorta↗