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P Amarenco

Publications and source records attributed to P Amarenco.

At least 19 recordsLinked to original sources
PubMed2006

Mannheim carotid intima-media thickness consensus (2004-2006). An update on behalf of the Advisory Board of the 3rd and 4th Watching the Risk Symposium, 13th and 15th European Stroke Conferences, Mannheim, Germany, 2004, and Brussels, Belgium, 2006.

Intima-media thickness (IMT) is increasingly used as a surrogate end point of vascular outcomes in clinical trials aimed at determining the success of interventions that lower risk factors for atherosclerosis and associated diseases (stroke, myocardial infarction and peripheral artery diseases). The necessity to promote further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT and to standardize IMT measurements is expressed through this updated consensus. Plaque is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. Standard use of IMT measurements is based on physics, technical and disease-related principles as well as agreements on how to perform, interpret and document study results. Harmonization of carotid image acquisition and analysis is needed for the comparison of the IMT results obtained from epidemiological and interventional studies around the world. The consensus concludes that there is no need to 'treat IMT values' nor to monitor IMT values in individual patients apart from exceptions named, which emphasize that inside randomized clinical trials should be performed. Although IMT has been suggested to represent an important risk marker, according to the current evidence it does not fulfill the characteristics of an accepted risk factor. Standardized methods recommended in this consensus statement will foster homogenous data collection and analysis. This will help to improve the power of randomized clinical trials incorporating IMT measurements and to facilitate the merging of large databases for meta-analyses.

Adult↗
PubMed2006

In vivo middle cerebral artery plaque imaging by high-resolution MRI.

Middle cerebral artery (MCA) atherosclerosis is currently diagnosed by indirect angiographic methods. The authors used high-resolution MRI (HR-MRI) to study MCA stenosis in six patients. At the level of stenosis, an MCA plaque was clearly delineated and significantly measured vs nonatherosclerotic MCA segments, showing that HR-MRI is an accurate direct imaging method.

Aged↗
PubMed2006

Predictors for malignant middle cerebral artery infarctions: a postmortem analysis.

BACKGROUND: Early detection of malignant infarction of the middle cerebral artery (MI-MCA) is important because of possible treatment by hemicraniectomy. OBJECTIVE: To investigate the anatomic and vascular predictors of MI-MCA. METHOD: The authors evaluated 192 consecutive autopsies of patients with nonlacunar cerebral infarction affecting the MCA territory. MI-MCA was defined by an infarct with temporal or central brain herniation and brain swelling. The autopsy protocol included a systematic analysis of intracranial arteries (including the bony segments of carotid and vertebral arteries and the circle of Willis), extracranial arteries, the aortic arch, and the heart. RESULTS: A total of 45 patients with MI-MCA were identified. Their median (range) survival time was 6 (0 to 20) days as compared with 18 (0 to 2,040) days for non-MI-MCA patients. Compared with non-MI-MCA, MI-MCA cases more frequently involved the superficial and deep MCA territory and were more frequently associated with anterior cerebral and anterior choroidal artery territory infarcts. Hemorrhagic transformation, Duret hemorrhages, carotid occlusion, and ipsilateral abnormalities of the circle of Willis were also more frequent (p < 0.05). Multivariable analysis showed that younger age, female sex, absence of stroke history, higher heart weight, carotid artery occlusion, and abnormal circle of Willis ipsilaterally were all independently associated with MI-MCA (p < 0.03). CONCLUSIONS: Typical pathologic pattern for development of malignant infarction of the middle cerebral artery is a carotid occlusion with abnormal ipsilateral circle of Willis in a young patient who had a first-ever large hemispheric stroke including the superficial territory with possibly a slight predominance of female sex.

Aged↗
PubMed2006

Diffusion weighted imaging of cerebellar lesions in Wernicke's encephalopathy.

We report unusual findings on MR imaging in a 62-year-old woman with Wernicke's encephalopathy (WE). Initial fluid-attenuated inversion recovery (FLAIR) and diffusion weighted MR imaging (DW-MRI) showed hyperintense lesions in the cerebellum and medial thalami, with a decreased apparent diffusion coefficient (ADC) in the cerebellum (reduced by 45%). After thiamine supplementation, the T2 and diffusion hyperintensities disappeared. However, clinical examination at three months showed persistent cerebellar impairment. The importance of the ADC values should be further investigated.

Cerebellar Diseases↗
PubMed2006

[Feasibility of percutaneous exclusion of the left atrial appendage: results of 11 cases].

Atrial fibrillation is associated with a risk of cerebral embolism, the only proven effective prevention of which is anticoagulant therapy. There is no known alternative in cases with contra-indications to this treatment. Percutaneous exclusion of the left atrial appendage by the implantation of a prosthesis (PLAATO System, ev3 Inc., Plymouth, Minnesota) is a new approach to the prevention of these complications. The authors report the results observed in a series of 11 consecutive patients (7 men, mean age 72 +/- 9 years) in whom this procedure was proposed. All patients had atrial fibrillation for over 3 months, were at high risk and had contra-indications to oral anticoagulants. The implantation of the prosthesis was performed after treatment with aspirin and clopidogrel, under general anaesthesia radioscopy and transoesophageal echocardiographic guidance with success in 9 cases (1 implantation refused in the catheter laboratory and 1 failure). The only complication observed was transient ST elevation treated by emergency angioplasty. The echographic and angiographic criteria of success of left atrial appendage exclusion were fulfilled in all implanted patients. The hospital course was uncomplicated. One recurrence of stroke was observed at the second month: transoesophageal echocardiography confirmed the absence of thrombosis, of migration of the prosthesis and its impermeability in all the patients. After 7 +/- 5 months' follow-up, no other adverse event was observed. This new procedure is technically feasible. Despite encouraging results, its long-term efficacy in the prevention of thromboembolic complications of atrial fibrillation remains to be demonstrated.

Aged↗
PubMed2004

Intracranial arterial dolichoectasia is associated with enlarged descending thoracic aorta.

BACKGROUND: Intracranial arterial dolichoectasia (IADE) is defined as an increase in length and diameter of the intracranial arteries and is present in 12% of stroke patients. The pathophysiology is unknown; some data suggest that IADE is not merely a complication of atherosclerosis, but a distinct arteriopathy characterized by loss of elastic tissue in the media. OBJECTIVE: To investigate the relationship between IADE and transesophageal echocardiography (TEE) variables such as ascending and descending thoracic aorta diameters. METHODS: The sample included 154 patients with brain infarction (BI) and with measurement of the descending thoracic aorta on TEE. IADE was diagnosed by consensus between two neurologists. Information on demographic characteristics and risk factors was collected using a structured questionnaire, and a carotid ultrasound scan was performed. RESULTS: IADE was identified in 23 of the 154 stroke patients (15%). The mean diameter (+/-SD) of the descending thoracic aorta was significantly higher in the IADE(+) than in the 131 IADE(-) stroke patients (mean +/- SD 26.6 +/- 3.6 vs 24.8 +/- 2.7 mm). The proportion of IADE increased regularly with the quartiles of descending thoracic aorta diameter: 5%, 13%, 18%, and 24% (test of linear trend, p = 0.02). The adjusted OR (95% CI) of IADE associated with a 1 mm increase in descending thoracic aorta diameter was 1.22 (95% CI, 1.02 to 1.45). CONCLUSION: Patients with intracranial arterial dolichoectasia (IADE) have larger descending thoracic aorta diameters than non-IADE patients, suggesting that the underlying process causing IADE also affects the descending thoracic aorta.

Aged↗
PubMed2004

Mannheim intima-media thickness consensus.

Intima-media thickness (IMT) is increasingly used in clinical trials as a surrogate end point for determining the success of interventions that lower risk factors for atherosclerosis. The necessity for unified criteria to distinguish early atherosclerotic plaque formation from thickening of IMT and to standardize IMT measurements is addressed in this consensus statement. Plaque is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness of > or =1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. Standard use of IMT measurements is recommended in all epidemiological and interventional trials dealing with vascular diseases to improve characterization of the population investigated. The consensus concludes that there is no need to 'treat IMT values' nor to monitor IMT values in individual patients apart from few exceptions. Although IMT has been suggested to represent an important risk marker, it does not fulfill the characteristics of an accepted risk factor. Standardized methods recommended in this consensus statement will foster homogenous data collection and analysis. This will help to improve the power of studies incorporating IMT measurements and to facilitate the merging of large databases for meta-analyses.

Arteriosclerosis↗
PubMed2004

[Socio-economic aspects of stroke management].

BACKGROUND: Stroke is the third leading cause of death and the first leading cause of disability in developed and developing countries. It is one of the most demanding public health problems to be faced in the upcoming years, particularly because of population aging. STATE OF THE ART: New therapeutic advances in the management of acute stroke have changed our perception of this condition and have had a major impact on healthcare organization and subsequently healthcare expenditures. Care required for the stroke victim is costly in both developing countries and in developed countries. Hemmorhagic events are the most costly, but their prevalence in Western countries is lower than ischemic events. Prevalence of ischemic events is higher in Asian countries. The direct costs of stroke, both for primary and secondary events, constitute the larger part of healthcare expenditures. The mean cost of stroke in France is estimated at 18,000 euros for the first 12 months. Disability accounts for 42 percent of the variable cost of stroke. During the first year, the acute phase accounts for 40 percent of the cost, rehabilitation and mid-term hospitalization for 29 percent, and ambulatory care for 8 percent. After 46 months, the cost of ambulatory care exceeds the cost of the first six months of care during and following the acute phase. CONCLUSION: Any improvement in the primary or secondary prevention of stroke will lead to a decrease in the incidence and prevalence of stroke, and any therapeutic advance capable of reducing disability will consequently reduce the overall cost of stroke.

France↗
PubMed2004

Multiple microembolic borderzone brain infarctions and endomyocardial fibrosis in idiopathic hypereosinophilic syndrome and in Schistosoma mansoni infestation.

We report two cases of multiple distal borderzone ischaemic strokes associated with hypereosinophilia due to idiopathic hypereosinophilic syndrome in one patient and to acute Schistosoma mansoni infestation in the other. Endomyocardial fibrosis (EMF) was documented pathologically, in one case at autopsy and in the other after cardiac surgery; and by cardiac CT, with initially negative echocardiography, in one patient. These observations suggest that so called borderzone infarcts may be due to microembolisms and that, in the context of hypereosinophilia, EMF diagnosis warrants complete cardiac investigation including cardiac CT and repeat echocardiography.

Adult↗
PubMed2003

Cost of a recurrent vs. cost of first-ever stroke over an 18-month period.

When assessing the cost-effectiveness of the secondary prevention of stroke, it is not well known whether the cost of a recurrent brain infarction (BI) is different from a first-ever BI. In a cohort of 435 consecutive prevalent cases of BI (including both recurrent and first-ever BI) we collected medical and socio-economic variables. Handicap was measured with the Rankin scale. Only the direct medical costs were considered over an 18-month period from a societal perspective. We compared first-ever to recurrent BI. Of the 435 patients 20.5% had a recurrent BI. The length of the initial hospitalization and the distribution of the patients into the three classes of handicap (Rankin 0-2, 3, and 4-5) were similar in the first-ever and recurrent BI groups. The average total cost of a first-ever BI was euro 19 725 (95% CI, 17 950-21 501) and euro 18 560 (95% CI, 15 798-21 322) for a recurrent BI (P = 0.48). There were no differences between the two groups when the costs were compared by handicap levels (P = 0.17) or when the costs were compared for each type of expenditure (initial hospitalization, rehabilitation, ambulatory services) except for long-term care, because of the small number of cases. This study suggests that the costs of recurrent BI are roughly similar to the costs of first-ever BI, which may be helpful when studying the cost-effectiveness of secondary stroke prevention trials.

Adolescent↗
PubMed2003

[Cerebral ischemic events and anti-cancer therapy].

Antineoplastic agents have been associated with cerebral hemorrhage, infarction and cerebral venous thrombosis. Infarctions have been reported in association with L-asparaginase, cisplatinium, methotrexate and 5-fluro-uracil. The mechanisms by which antineoplastic agents may lead to stroke include endothelium toxicity and abnormalities of coagulation factors.

Adolescent↗
PubMed2002

Reversible leukoencephalopathy in cerebral amyloid angiopathy presenting as subacute dementia.

This report concerns a 71-year-old woman who had rapid progressive dementia along with myocloni and increased blood pressure. Cranial computed tomography and magnetic resonance imaging scans showed bilateral widespread white matter changes with mass effect. A brain biopsy revealed an amyloid angiopathy in leptomeningeal as well as cerebral cortex arteries. After 2 months of antihypertensive treatment, a dramatic improvement of cognitive functions and a spectacular regression of leukoencephalopathy were observed. We suggest that hypertensive encephalopathy may worsen or reveal cerebral amyloid angiopathy.

Aged↗