N-terminal pro-B-type natriuretic peptide testing improves the management of patients with suspected acute heart failure: primary results of the Canadian prospective randomized multicenter IMPROVE-CHF study.
BACKGROUND
The diagnostic utility of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in heart failure has been documented. However, most of the data were derived from countries with high healthcare resource use, and randomized evidence for utility of NT-proBNP was lacking.


RESULTS
We tested the hypothesis that NT-proBNP testing improves the management of patients presenting with dyspnea to emergency departments in Canada by prospectively comparing the clinical and economic impact of a randomized management strategy either guided by NT-proBNP results or without knowledge of NT-proBNP concentrations. Five hundred patients presenting with dyspnea to 7 emergency departments were studied. The median NT-proBNP level among the 230 subjects with a final diagnosis of heart failure was 3697 compared with 212 pg/mL in those without heart failure (P<0.00001). Knowledge of NT-proBNP results reduced the duration of ED visit by 21% (6.3 to 5.6 hours; P=0.031), the number of patients rehospitalized over 60 days by 35% (51 to 33; P=0.046), and direct medical costs of all ED visits, hospitalizations, and subsequent outpatient services (US $6129 to US $5180 per patient; P=0.023) over 60 days from enrollment. Adding NT-proBNP to clinical judgment enhanced the accuracy of a diagnosis; the area under the receiver-operating characteristic curve increased from 0.83 to 0.90 (P<0.00001).


CONCLUSIONS
In a universal health coverage system mandating judicious use of healthcare resources, inclusion of NT-proBNP testing improves the management of patients presenting to emergency departments with dyspnea through improved diagnosis, cost savings, and improvement in selected outcomes.
Moe
Gordon W
GW
University of Toronto, St Michael's Hospital, Toronto, Ontario, Canada. moeg@smh.toronto.on.ca
Howlett
Jonathan
J
Januzzi
James L
JL
Zowall
Hanna
H
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care / Q000191:economics; D009320:Atrial Natriuretic Factor / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002170:Canada; D017046:Cost Savings; D004417:Dyspnea / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy; D004632:Emergency Medical Services / Q000191:economics; D005260:Female; D005102:Health Expenditures; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis / Q000191:economics / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009313:National Health Programs / Q000191:economics; D017063:Outcome Assessment, Health Care / Q000191:economics*; D010359:Patient Readmission / Q000191:economics; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*
D015415:Biomarkers; C099254:N-terminal proatrial natriuretic peptide; D011498:Protein Precursors; D009320:Atrial Natriuretic Factor