Paradoxical use of invasive cardiac procedures for patients with non-ST segment elevation myocardial infarction: an international perspective from the CRUSADE Initiative and the Canadian ACS Registries I and II.
BACKGROUND
Practice guidelines support an early invasive strategy in patients with non-ST segment elevation acute coronary syndromes, particularly in those at higher risk.


OBJECTIVE
To compare North American rates of invasive cardiac procedure use stratified by risk.


METHODS
Use of invasive cardiac procedures and other care patterns in patients with non-ST segment elevation acute coronary syndromes from the United States (US) Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the ACC/AHA guidelines (CRUSADE) National Quality Improvement Initiative (n=88,097; 465 hospitals) and Canadian ACS Registries I (n=1270; 51 hospitals) and II (n=1473; 36 hospitals) were compared after dividing patients into different risk categories based on predicted risk of in-hospital mortality.


RESULTS
While the overall use of invasive procedures was higher in the US, high-risk patients were least likely to undergo coronary angiography (41% versus 64% in Canada [P<0.0001] and 53% versus 76% in the United States [P<0.0001]) and percutaneous coronary intervention (14% versus 32% in Canada [P<0.0001] and 28% versus 51% in the US [P<0.0001]) compared with low-risk patients in both countries, and had longer median waiting times for these procedures (120 h versus 96 h in Canada [P<0.0001] and 34 h versus 23 h in the US [P<0.0001] for coronary angiography).


CONCLUSIONS
The inverse relationship between risk level and the use of invasive cardiac procedures for patients in the US and Canada suggests that a risk stratification-guided approach for triaging patients to an early invasive management strategy is paradoxically used. This incongruous relationship holds true regardless of resource availability or overall rates of cardiac catheterization.
Zia
Mohammad I
MI
Canadian Heart Research Centre, Toronto, Canada.
Goodman
Shaun G
SG
Peterson
Eric D
ED
Mulgund
Jyotsna
J
Chen
Anita Y
AY
Langer
Anatoly
A
Tan
Mary
M
Ohman
E Magnus
EM
Gibler
W Brian
WB
Pollack
Charles V
CV
Roe
Matthew T
MT
D054058:Acute Coronary Syndrome / Q000175:diagnosis; D000368:Aged; D000789:Angina, Unstable / Q000175:diagnosis / Q000188:drug therapy / Q000601:surgery*; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data; D002170:Canada; D006328:Cardiac Catheterization / Q000706:statistics & numerical data; D004562:Electrocardiography; D005260:Female; D019983:Guideline Adherence; D006801:Humans; D038622:Internationality; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000188:drug therapy / Q000601:surgery*; D017410:Practice Guidelines as Topic; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014218:Triage; D014481:United States