The effect of cardiac troponin testing on clinical care in a veterans population: a randomized controlled trial.
BACKGROUND
Cardiac troponin is more accurate than creatine kinase (CK) testing for detecting myocardial injury in patients with acute coronary syndromes (ACS), but its effects on clinical care compared with CK testing alone is open to question.


OBJECTIVE
To test the effects of troponin I on medical decisions for patients undergoing cardiac enzyme testing.


METHODS
Randomized, controlled trial.


METHODS
Urban academic Veterans Affairs medical center.


METHODS
Three hundred ninety-two patients presenting to the emergency department (ED) and outpatient settings with symptoms and/or electrocardiograms suggestive but not diagnostic of ACS.


METHODS
Random assignment to linked CK-troponin I (CKTnI) testing or CK testing alone.


METHODS
ED discharge and cardiac catheterization incidence (primary); ED medication use, inpatient noninvasive testing, revascularization procedures, discharge medications, and 8-week ED visits, hospitalizations, and procedures (secondary).


RESULTS
Groups were similar in all variables except history of heart failure (CK 26.8% vs CKTnI 17.0%). ACS comprised 12.2% of the cohort. ED discharge incidence was greater in the CKTnI arm (18% vs 9.6%; relative risk [RR], 1.83; 95% CI, 1.08 to 3.31; P=.02; number needed to test=12.6; 95% CI, 4.5 to 130). Troponin testing had no significant effect on catheterization incidence (18.2% vs 14.5%; RR, 1.19; 95% CI, 0.72 to 1.92; P>.20) or other outcomes except follow-up echocardiography (13.4% vs 7.4%; RR, 2.24; 95% CI, 1.11 to 4.69; P=.02).


CONCLUSIONS
In a veterans population undergoing cardiac enzyme testing, CKTnI testing led to more ED discharges than CK testing alone but had no effect on inpatient care and was associated with more echocardiograms in a follow-up period.
Berkwits
Michael
M
Philadelphia VA Medical Center and the Division of General Internal Medicine, University of Pennsylvania Health System, Philadelphia, PA, USA. berkwits@mail.med.upenn.edu
Localio
A Russell
AR
Kimmel
Stephen E
SE
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D006328:Cardiac Catheterization; D003327:Coronary Disease / Q000097:blood / Q000175:diagnosis* / Q000628:therapy; D003402:Creatine Kinase / Q000097:blood*; D004636:Emergency Service, Hospital; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017063:Outcome Assessment, Health Care; D019210:Troponin I / Q000097:blood*; D014481:United States; D014728:Veterans
D015415:Biomarkers; D019210:Troponin I; D003402:Creatine Kinase