Voici des extraits de la m�ta-analyse de Cochrane qui m'apparaissent fort
int�ressants. On consid�re l'anticoagulation aigu lorsqu'effectu�e dans les
2 SEMAINES de l'�pisode. Aucune cat�gorie de patients ne semble b�n�ficier
du traitement. Certains passages mettent en doute la pertinence de
l'anticoagulation prophylaxique pour la MTE dans ce contexte. Ceux qui sont
int�ress�s � avoir le texte complet peuvent me le faire savoir (PDF de 437
kb).

"...Acute stroke treatments should aim to prevent disability as well as
death, lest patients survive their acute stroke only to remain severely
disabled. The present randomised evidence indicates that routine immediate
anticoagulation does not provide any net short or long-term reduction in
death or disability. Although immediate anticoagulation leads to fewer
recurrent ischaemic strokes, avoiding nine ischaemic strokes per 1000
patients treated, this benefit is entirely offset by a similar-sized
increase in the number of intracranial haemorrhages. The net result is no
short- or long-term benefit..."

"iii) Prevention of deep vein thrombosis and pulmonary embolism in acute
ischaemic stroke.

In patients with presumed or confirmed ischaemic stroke, allocation to
immediate anticoagulation was associated with a highly significant 79%
reduction in the odds of deep vein thrombosis during the treatment period,
similar to that seen with the use of prophylactic heparin in patients
undergoing different types of surgery (Collins et al 1988).

In this systematic review, the reductions in deep vein thrombosis with acute
anticoagulation were substantial, with 281 deep vein thromboses prevented
per 1,000 patients treated. However, as mentioned previously, this estimate
is based on relatively small numbers of patients, and most of the deep vein
thromboses detected were asymptomatic. In addition, there was significant
heterogeneity in the effects of treatment which was difficult to explain.

If however, one accepts the estimate of treatment effect, it is then
difficult to assess the extent to which it may be generalisable. The stroke
patients included in the trials of anticoagulants to prevent deep vein
thrombosis generally had quite severe strokes, and paralysis of one leg
(with the attendant high risk of deep vein thrombosis) was almost invariably
present at randomisation. Furthermore, with the widespread intorduction of
Stroke Units, with policies of early mobilisation and good hydration, the
risk of deep vein thrombosis may well be lower.

In addition to deep vein thrombosis prevention, the risk of pulmonary
embolism was also reduced significantly with the use of anticoagulants (OR
0.61; CI 0.45 - 0.83), with an additional four pulmonary emboli avoided per
1000 patients treated. The overall risk of pulomary embolism appeared to be
low, and the absolute benefit was small, and so the apparent reduction in
deep vein thrombosis may have little clinical relevance if there is not a
correspondingly large reduction in pulmonary embolism. However, there may
well have been under-ascertainment of pulmonary embolism in all of the
trials, since pulmonary emboli were not sought systematically. In addition,
deep vein thrombosis can lead to morbidity (eg. post-phlebitic leg and
varicose ulcers), but data on these outcomes were not available from the
trials.

If anticoagulants result in no net increase or decrease in long-term death
or disability, but do lead to a reduction in the number of deep vein
thromboses and pulmonary emboli (albeit in immobile patients at higher
risk), then the benefit of fixed heparin regimens associated with a low risk
of bleeding (eg. low fixed-dose unfractionated heparin) may yet outweigh the
increased risk of haemorrhage. Unfortunately, there were insufficient
randomised data comparing low-dose heparin to aspirin, or to
non-pharmacological interventions such as compression stockings or early
mobilisation, to determine what the most effective and safe antithrombotic
regimen for deep vein thrombosis prophylaxis might be.

However, it is interesting to note from the IST (IST 1997) that the
frequency of fatal and non-fatal symptomatic pulmonary embolism (perhaps a
surrogate for the occurrence of deep vein thrombosis) was very similar among
patients allocated low dose subcutaneous heparin alone (0.8%) and aspirin
alone (0.7%). Aspirin alone may therefore be an adequate antithrombotic
agent to be used for routine deep vein thrombosis prophylaxis in many
patients with acute ischaemic stroke. There is substantial evidence to
support the use of antiplatelets in deep vein thrombosis and pulmonary
embolism prophylaxis in other categories of high-risk patients (APT 1994b).

Finally, it is possible that once anticoagulants are stopped, rebound
thrombosis could occur, and deep vein thromboses may begin to develop. We
were unable to exclude this possibility because no trials sought deep vein
thrombosis systematically after the treatment period. "

v) Different categories of patient..

This systematic review provides information about the use of anticoagulants
in stroke patients in general, as well as limited information about various
subgroups. It is recognised that the evaluation of subgroups should only be
undertaken with caution due to the increased potential for error due to the
smaller numbers of patients and outcomes being evaluated. With that
qualification in mind, the small amounts of (randomised) sub-group data
evaluated here do not provide any evidence to support the routine use of
anticoagulants in any specific category of stroke patient, including those
with: cardioembolic stroke, 'stroke in progression', vertebrobasilar
territory stroke, or following thrombolysis for acute ischaemic stroke to
prevent re-thrombosis of the treated cerebral artery."


MC







----- Original Message -----
From: "paulaye" <[EMAIL PROTECTED]>
To: "URG-L Mailing List" <[EMAIL PROTECTED]>
Sent: Monday, December 10, 2001 5:21 AM
Subject: URG-L: RE: URG-L: Re: URG-L: RE: URG-L: FA et accident isch�mique
c�r�bral. 


ATTENTION!!!
Ne me faites pas dire ce que je n'ai pas dit.
- Il faut faire le SCAN en urgence!!!
- IL est FORMELLEMENT indiqu� d'administrer de l'HBPM SC � DOSES PREVENTIVES
dans l'AVC isch�mique, ce en pr�vention de la maladie thromboembolique. La
discussion portait sur l'anticoagulation curative
Par ailleurs, il persiste de rares indications � l'anticoagulation
th�rapeutique :
1- les porteurs de valve m�canique (relais des AVK)
2- 2 situations, o� m�me en l'absence de preuve certaine, il y a un fort
consensus professionnel : la dissection carotidienne, et la thrombophl�bite
c�r�brale (voir �tude de l'�quipe de Heidelberg)

Répondre à