Pierre Garnier

Université Jean Monnet, Saint-Étienne, Rhône-Alpes, France

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Publications (10)7.67 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: Purpose To compare magnetic resonance imaging (MRI) brain feature in cryptogenic stroke patients with patent foramen ovale (PFO), cryptogenic stroke patients without PFO and patients with cardioembolic stroke. Materials and methods The ethics committee required neither institutional review board approval nor informed patient consent for retrospective analyses of the patients’ medical records and imaging data. The patients’ medical files were retrospectively reviewed in accordance with human subject research protocols. Ninety-two patients under 60 years of age were included; 15 with cardioembolic stroke, 32 with cryptogenic stroke with PFO and 45 with cryptogenic stroke without PFO. Diffusion-weighted imaging of brain MRI was performed by a radiologist blinded to clinical data. Univariate, Fischer's exact test for qualitative data and non-parametric Wilcoxon test for quantitative data were used. Results There was no statistically significant difference found between MRI features of patients with PFO and those with cardioembolic stroke (p<.05). Patients without PFO present more corticosubcortical single lesions (p<.05) than patients with PFO. Patients with PFO have more often subcortical single lesions larger than 15 mm, involvement of posterior cerebral arterial territory and intracranial occlusion (p<.05) than patient with cryptogenic stroke without PFO. Conclusion Our study suggests a cardioembolic mechanism in ischemic stroke with PFO.
    European journal of radiology 01/2014; · 2.65 Impact Factor
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    ABSTRACT: Drug-drug interactions may contribute to the variability of the response of clopidogrel. Several hypotheses have been proposed concerning the potential modification of clopidogrel pharmacokinetics and pharmacodynamics by fluoxetine. This open-label crossover study assessed the effect of fluoxetine on the pharmacological activity of clopidogrel in healthy volunteers. Eight healthy male volunteers received a single 600-mg loading dose of clopidogrel followed by 20 mg of fluoxetine on 4 days and then 20 mg of fluoxetine plus 600 mg of clopidogrel on the fifth day. Eleven blood samples were withdrawn after clopidogrel administration to determine plasma concentrations of clopidogrel active metabolite (CAM) and platelet function. Platelet aggregation was measured by light transmittance aggregometry (LTA) and platelet reactivity index by flow cytometric vasodilator-stimulated phosphoprotein (VASP) analysis. The areas under the curve and maximum plasma concentrations of CAM were, respectively, 20.6 and 25.3% lower after co-administration of fluoxetine compared with administration of clopidogrel alone. The percentage maximum platelet aggregation values in the presence of 5 μm and 10 μm adenosine diphosphate, measured by LTA, were, respectively, 13.9 and 22.4% lower after fluoxetine co-administration. The platelet reactivity index measured by the flow cytometric VASP method was 36.8% lower when clopidogrel was administered in conjunction with fluoxetine.
    Fundamental and Clinical Pharmacology 02/2013; · 1.99 Impact Factor
  • Revue Neurologique 02/2013; · 0.51 Impact Factor
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    ABSTRACT: Few vascular dementias are diagnosed in memory clinic consultations. One type, a rare etiology, Sneddon syndrome, can lead patients to consult for an isolated memory complaint. We report the cases of two patients, aged 63 and 66 years, who presented frontocortical cognitive profile and behavior disorders. Seronegative Sneddon syndrome, complicated with dementia, was diagnosed in each case by noticing an association between, on MRI, an atrophy and several ischemic cerebrovascular accident aftermaths, and a livedo racemosa. Management of vascular risks factors improves the prognosis.
    Revue Neurologique 02/2013; 169(2):169–172. · 0.51 Impact Factor
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    ABSTRACT: Ischemic stroke has many etiologies but in 30% of patients the mechanism remains unknown, leading to a search for rare causes. We report the case of a 64-year-old man with no known vascular risk factor. The patient was a hiker who presented isolated phasic disorders leading to the diagnosis of a transient ischemic attack (TIA). The etiological search remained negative excepting for the frail irregular aspect of the left sylvian artery implicated in the symptoms. The patient then developed vertigo without any MRI signs of a vascular event. Lyme serology, in both blood and CSF samples enabled the diagnosis of neuroborreliosis to which the TIA was secondarily attributed due to the vasculitis of the left sylvian artery. Antibiotic therapy provided cure. Lyme disease is a rare cause of stroke but should always be entertained as a possible diagnosis since there is a curative treatment.
    Pratique Neurologique - FMC 02/2013; 4(1):28–31.
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    ABSTRACT: Objectif Analyser les facteurs influençant le délai d’admission aux urgences des patients ayant un accident vasculaire cérébral ischémique aigu (AVCi). Méthodes Entre mai 2006 et juillet 2007, tous les patients admis aux urgences pour suspicion d’AVC ont été inclus. Les caractéristiques des patients ont été recueillies aux urgences, de même que les événements consécutifs à la constatation du déficit ainsi que l’horaire de leur survenue : constatation des symptômes, nature de l’appelant, destination de l’appel, moyens mis en jeu pour répondre (visite, consultation d’un médecin, intervention médicalisée), modalité du transport vers la structure hospitalière. L’analyse a comporté un descriptif de la population globale et une comparaison entre les patients admis avant ou après la 3e heure suivant leurs symptômes (groupes I et II respectivement). Le diagnostic final d’AVCi a été retenu à la sortie du service hospitalier. Les résultats ont été exprimés par la moyenne (± ds) ou la médiane (interquartile), les comparaisons ont été effectuées à l’aide des tests de Mann-Whitney et du Chi2 (p < 0,05). Résultats Parmi 678 patients admis pour suspicion d’AVC, 536 étaient des AVCi, 65 des accidents hémorragiques, 3 des thromboses veineuses cérébrales et 74 ne correspondaient pas à une maladie neurovasculaire aiguë. Les résultats de cette étude ont porté sur 536 patients, d’âge médian 75 ans dont 166 (31 %, groupe I) ont été admis dans les 3 heures et 370 au-delà (groupe II). Le délai médian entre l’apparition des signes fonctionnels et l’appel a été de 15 minutes (1–26) dans le groupe I et de 300 (60–960) dans le groupe II (p < 0,0001). Les délais médians d’intervention d’un médecin (traitant, de garde, SMUR) étaient de 10 à 60 minutes. Selon le type de transport employé, les délais médians de ce dernier étaient de 30 à 120 minutes. Les différences entre les groupes I et II ont été : une réduction du taux de prise en charge par un médecin avant l’admission aux urgences (40 % vs 72 %, p < 0,0001), une augmentation du recours au centre 15 (42 % vs 17 %, p < 0,001), la présence d’un entourage lors de l’apparition des signes fonctionnels (58 % vs 39 %, p < 0,01), un transport direct sans intervention médicalisée (49 vs 11 %). Enfin, sans tenir compte de la notion de délai, 12 % des patients de cette étude étaient éligibles à une thrombolyse intraveineuse. Conclusion En cas de suspicion d’AVC, ces résultats plaident en faveur d’un appel au centre 15 pour régulation suivie, si possible sans intervention médicale, d’un transport immédiat vers la structure adaptée. Ce qui était connu•Le délai d’admission des patients ayant un accident vasculaire cérébral dans des structures d’urgence à l’étranger.•Le raccourcissement de ces délais obtenus par la mise en place de programmes d’informations auprès de tous les acteurs de la filière de prise en charge de cette maladie.Ce qu’apporte l’article•Connaissance des délais d’admission dans une structure d’urgence Française des patients ayant un accident vasculaire cérébral aigu.•La sous utilisation du recours au centre 15.•La nécessité d’intensifier les campagnes d’information auprès du grand public en France.•La nécessité d’une meilleure information auprès des professionnels de santé.
    La Presse Médicale. 11/2012; 41(11):e559–e567.
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    ABSTRACT: OBJECTIVE: To analyse the factors influencing the time of admission of patients presenting an acute ischaemic stroke (AIS) to the emergency department. PATIENTS AND METHODS: Between May 2006 and July 2007, all patients with suspected stroke admitted to the emergency department were included. Patients' characteristics and the nature and timing of the events following symptom detection were recorded in the emergency department. The symptoms observed, the person telephoning for help, the person or establishment contacted, the measures implemented (attendance of a physician, medical or paramedical intervention) and the means of transport to the hospital were noted. The overall population was analysed descriptively and patients admitted within 3hours of symptom onset (group I) were compared with those admitted after a longer interval (group II). The final diagnosis of AIS was confirmed on patient discharge. The results were expressed as the mean (±SD) or median (interquartile range), Mann-Whitney and Chi(2) tests being used to analyse differences between the two groups (threshold of statistical significance: P<0.05). RESULTS: Among the 678 patients admitted with suspected stroke, 536 were diagnosed as having experienced an AIS, 65 a haemorrhagic stroke, 3 a cerebral venous thrombosis and 74 an event other than an acute neurovascular event. The results therefore concern 536 patients (median age: 75 years), of whom 166 (31%, group I) were admitted within 3hours of symptom onset and 370 after a longer interval (group II). The median time between symptom onset and the call for help was 15min (1-26) in group I and 300min (60-960) in group II (P<0.0001). The median times to intervention of a physician (the patient's regular general practitioner, the physician on duty, or the SMUR [Mobile Emergency and Resuscitation Service] physician) ranged from 10 to 60min. Median transport times ranged from 30 to 120min depending on the type of transport employed. The two groups differed significantly with regard to intervention of a physician before admission to the emergency department (40% of patients in group I vs. 72% in group II, P<0.0001), initial call to the emergency medical call centre ("15" in France) (42% vs. 17%, P<0.001), presence of a relative or other person at the time of functional symptom onset (58% vs. 39%, P<0.01), and immediate transport to hospital without medical intervention (49 vs. 11%). Finally, irrespective of the time to hospital admission, 12% of the patients studied were eligible for intravenous thrombolysis. CONCLUSION: In the event of a suspected stroke, these results favour contacting the emergency medical call centre and immediate transfer of the patient to an appropriate hospital establishment without waiting for prior medical intervention.
    La Presse Médicale 05/2012; · 0.87 Impact Factor
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    ABSTRACT: We present the case of a 34-year-old woman who developed, in postpartum period of an uncomplicated pregnancy, a thunderclap headache with visual disturbance associated with a severe arterial hypertension. Both clinical evolution and cerebral imaging including angio-MR confirmed the diagnosis of postpartum reversible vasoconstriction syndrome. One of the leading causes of this syndrome is the use of vasoactive drugs as it was observed in the case of this patient. It is important to consider this syndrome in the differential diagnosis in patients presenting with headache in the postpartum period.
    Annales francaises d'anesthesie et de reanimation 01/2011; 30(1):61-3. · 0.77 Impact Factor
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    ABSTRACT: We present the case of a 34-year-old woman who developed, in postpartum period of an uncomplicated pregnancy, a thunderclap headache with visual disturbance associated with a severe arterial hypertension. Both clinical evolution and cerebral imaging including angio-MR confirmed the diagnosis of postpartum reversible vasoconstriction syndrome. One of the leading causes of this syndrome is the use of vasoactive drugs as it was observed in the case of this patient. It is important to consider this syndrome in the differential diagnosis in patients presenting with headache in the postpartum period.
    Annales Francaises D Anesthesie Et De Reanimation - ANN FR ANESTH REANIM. 01/2011; 30(1):61-63.
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    ABSTRACT: Objective. Intracranial hemorrhage (ICH) is an antithrombotic treatment complication. Our study's goal is to assess the proportion of ICH occurring while the patient is on antithrombotic treatment. The secondary goal is to assess the proportion of "avoidable" ICH (anticoagulant overdosage, debatables indications). Methods. We conducted a descriptive epidemiological single-center study of ICH during 2 years. We analyzed the type of ICH, the type of antithrombotic treatment, the level of anticoagulation and the relevance of antithrombotic treatment indication. Results. Of the 400 patients admitted for an ICH, 131 (33%) were traited by antithrombotic therapy: oral anti-vitamin K anticoagulants (VKA) in 14.1% of cases and antiplatelet agents in 15.1%. Of VKA patients, overdosage rate was 30.2%. The indication of antithrombotic therapy was debatable in 18.3% of cases. Conclusion. Our study highlights the frequency of ICH occuring on antithrombotic therapy and the significant proportion of "avoidable" ICH.
    Thérapie 68(3):143-7. · 0.37 Impact Factor