Abstract
Background
Canadian atrial fibrillation (AF) guidelines recommend that all AF patients be risk
stratified with respect to stroke and bleeding, and that most should receive antithrombotic
therapy.
Methods
As part of the Canadian Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation (FREEDOM AF) chart audit, data were collected on 4670 patients ≥ 18 years
old without significant valvular heart disease from the primary care practices of
474 physicians (February to September, 2011).
Results
Physicians did not provide an estimate of stroke and bleeding risk in 15% and 25%
of patients, respectively. When risks were provided, they were on the basis of a predictive
stroke and bleeding risk index in only 50% and 26% of patients, respectively. There
were over- and underestimation of stroke and bleeding risk in a large proportion of
patients. Antithrombotic therapy included warfarin (90%); 24% of patients had a time
in the therapeutic range (TTR) < 50%, 9% between 50% and 60%, 11% between 60% and
70%, and 56% had a TTR ≥ 70%.
Conclusions
In a large Canadian AF population, primary care physicians did not provide a stroke
or bleeding risk in a substantial proportion of their AF patients. When estimates
were provided, they were on the basis of a predictive stroke and bleeding risk index
in less than half of the patients. Furthermore, there was under- and overestimation
of stroke and bleeding risk in a substantial proportion of patients. As many as 1
in 3 patients receiving warfarin have their TTR < 60%. These findings suggest an opportunity
to enhance knowledge translation to primary care physicians.
Résumé
Introduction
Selon les lignes directrices canadiennes sur la fibrillation auriculaire (FA), il
est recommandé que tous les patients fassent l’objet d’une stratification du risque
relativement aux accidents vasculaires cérébraux (AVC) et aux hémorragies et que la
plupart d’entre eux reçoivent un traitement antithrombotique.
Méthodes
Dans le cadre du projet canadien de revue de dossiers médicaux intitulé FREEDOM AF
(Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation), des données ont été recueillies sur 4670 patients âgés de 18 ans ou plus ne présentant
pas de valvulopathie importante à partir de dossiers tenus par 474 médecins de soins
primaires (de février à septembre 2011).
Résultats
Les médecins n’avaient indiqué aucune donnée relative au risque d’AVC et d’hémorragie
dans 15 % et 25 % des cas, respectivement. Lorsqu’il y avait mention du risque, celui-ci
était basé sur un indice de prédiction du risque d’AVC et d’hémorragie pour seulement
50 % et 26 % des patients, respectivement. En outre, dans une forte proportion des
cas, le risque d’AVC et d’hémorragie avait été soit surestimé, soit sous-estimé. Parmi
les traitements antithrombotiques administrés, on comptait notamment la warfarine
(90 %); 24 % des patients recevant ce traitement avaient un temps dans la marge thérapeutique
(TMT) inférieur à 50 %, 9 % des patients avaient un TMT entre 50 et 60 %, 11 % des
patients avaient un TMT entre 60 et 70 %, et 56 % des patients avaient un TMT égal
ou supérieur à 70 %.
Conclusion
Dans une importante population de patients canadiens, les médecins de soins primaires
n’ont pas indiqué de risque d’AVC et d’hémorragie pour une grande proportion des patients
atteints de FA, et lorsqu’un tel risque était indiqué, il était basé sur un indice
de prédiction du risque d’AVC et d’hémorragie pour moins de la moitié des patients.
De plus, il y avait eu surestimation ou sous-estimation du risque d’AVC et d’hémorragie
pour une importante proportion de patients. Enfin, chez les patients traités par la
warfarine, 1 sur 3 avait un TMT inférieur à 60 %. De tels résultats suggèrent qu’il
serait souhaitable d’améliorer la formation des médecins de soins primaires dans ce
domaine d’application.
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Article info
Publication history
Published online: October 14, 2015
Accepted:
July 15,
2015
Received:
December 8,
2014
Footnotes
See editorial by Macle and Andrade, pages 278-280 of this issue.
See page 342 for disclosure information.
Identification
Copyright
© 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
