Can J Cardiol Vol 20 No 5 April 2004 491
Cardiac procedures after an acute myocardial infarction
across nine Canadian provinces
Louise Pilote MD MPH PhD
1
, Patrick Merrett BSc
1
, Igor Karp MD MPH
1
, David Alter MD PhD
2
,
Peter C Austin PhD
2,6
, Jafna Cox MD
3
, Helen Johansen PhD
4
, William Ghali MD MPH
5
, Jack V Tu MD PhD
2
1
McGill University Health Centre at the Montreal General Hospital, Montreal, Quebec;
2
Institute of Clinical Evaluative Sciences, Toronto,
Ontario;
3
Dalhousie University, Halifax, Nova Scotia;
4
Statistics Canada;
5
University of Calgary, Calgary, Alberta;
6
Department of Public
Health Sciences, University of Toronto, Toronto, Ontario
Correspondence and reprints: Dr Louise Pilote, Division of Clinical Epidemiology, Montreal General Hospital, 1650 Cedar Street, Montreal,
Quebec H3G 1A4. Telephone 514-934-1934 ext 44722, fax 514-934-8293, e-mail louise.pilote@mcgill.ca
Received for publication January 23, 2003. Accepted February 12, 2003
L Pilote, P Merrett, I Karp, et al. Cardiac procedures after an
acute myocardial infarction across nine Canadian provinces.
Can J Cardiol 2004;20(5):491-500.
BACKGROUND: Geographical variations in the use of invasive
cardiac procedures have been documented. It remains unclear to
what extent these variations exist across the Canadian provinces.
OBJECTIVE: To describe variation in the use of invasive cardiac
procedures and waiting times for these procedures across nine
Canadian provinces.
METHODS: Using longitudinal, de-identified patient data from the
Canadian Institute for Health Information, records of patients who
had suffered an acute myocardial infarction (AMI) in each of nine
Canadian provinces between 1997/1998 and 1999/2000 were selected.
Rates and median waiting times for percutaneous coronary interven-
tion and coronary artery bypass graft surgery were calculated by age,
sex and health region.
RESULTS: There was a large variation in the use of and waiting
times for invasive cardiac procedures across the Canadian provinces
studied. In general, cardiac procedure rates in Western provinces
were higher than in Eastern provinces, most notably higher than in
the Maritime provinces and Ontario. In addition to interprovincial
variation, there was also significant regional variation in the rates of
revascularization and waiting times. Rates of percutaneous coronary
intervention increased over the study period, whereas rates of bypass
surgery remained relatively stable.
CONCLUSIONS: Significant variation in the use of cardiac proce-
dures after AMI exists across Canada and this may represent poten-
tial inequalities in the treatment of AMI across Canada.
Key Words: Acute myocardial infarction; Canada, Revascularization
Les interventions cardiaques après un
infarctus aigu du myocarde dans neuf
provinces canadiennes
HISTORIQUE : Les variations géographiques dans l’utilisation des
interventions cardiaques envahissantes ont été documentées. On ne
connaît toutefois pas la mesure de ces variations au Canada.
OBJECTIF : Décrire la variation dans l’utilisation des interventions
cardiaques envahissantes et les délais d’attente à l’égard de ces
interventions dans neuf provinces canadiennes.
MÉTHODOLOGIE : Au moyen de données longitudinales de patients
anonymes tirées de l’Institut canadien d’information pour la santé, des
dossiers de patients ayant souffert d’un infarctus aigu du myocarde (IAM)
ont été sélectionnés dans chacune des neuf provinces canadiennes entre
1997-1998 et 1999-2000. Les taux et les délais d’attente médians pour les
interventions coronaires percutanées et les pontages aortocoronariens ont
été calculés selon l’âge, le sexe et la région sanitaire.
RÉSULTATS : On a remarqué une forte variation dans l’utilisation et les
délais d’attente des interventions cardiaques envahissantes entre les
provinces canadiennes à l’étude. En général, les taux d’intervention dans
les provinces de l’ouest étaient plus élevées que dans celles de l’est, et
surtout plus élevés que dans les Maritimes et en Ontario. Outre la
variation interprovinciale, on observait également une variation
régionale marquée dans les taux de revascularisation et de délais d’attente.
Les taux d’interventions coronaires percutanées ont augmenté pendant la
période de l’étude, tandis que ceux de pontage sont demeurés
relativement stables.
CONCLUSIONS : Il existe une variation significative dans l’utilisation
d’interventions cardiaques après l’IAM au Canada, ce qui peut
représenter des inégalités potentielles dans le traitement de l’IAM au
Canada.
A
cute myocardial infarction (AMI) is the leading cause
of mortality in Canada and its treatment places a large
financial burden on the health care system. Large regional
variations in the use of cardiac procedures after AMI, such
as percutaneous coronary intervention (PCI) and coronary
artery bypass graft (CABG) surgery, have been documented
across North America (1-3) and Europe (4,5). Similarly,
large variations in the use of revascularization procedures
after AMI have been identified within Canadian provinces,
notably Manitoba (6,7), Ontario (8,9) and Quebec (10).
Variations in waiting times for coronary revascularization
have also been identified across Europe and the United
States (11). However, few studies to date have examined to
what extent these variations exist among the Canadian
provinces (12).
To document variation in the treatment of AMI across
Canada, we compared temporal trends in treatment rates and
waiting times for two common cardiac procedures, PCI and
CABG, among patients suffering from an AMI across nine
Canadian provinces.
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