Heart-type fatty acid binding protein (H-FABP) in patients in an emergency department setting, suspected of acute coronary syndrome: optimal cut-off point, diagnostic value and future opportunities in primary care.
BACKGROUND
Most patients presenting chest complaints in primary care are referred to secondary care facilities, whereas only a few are diagnosed with acute coronary syndrome (ACS).


OBJECTIVE
The aim is to determine the optimal cut-off value for a point-of-care heart-type fatty acid binding protein (H-FABP) test in patients presenting to the emergency department and to evaluate a possible future role of H-FABP in safely ruling out ACS in primary care.


METHODS
Serial plasma H-FABP (index test) and high sensitivity troponin T (hs-cTnT) (reference test) were determined in patients with any new-onset chest complaint. In a receiver operating characteristic (ROC) curve, the optimal cut-off value of H-FABP for ACS was determined. Predictive values of H-FABP for ACS were calculated.


RESULTS
For 202 consecutive patients (prevalence ACS 59%), the ROC curve based on the results of the first H-FABP was equal to the ROC curve of hs-cTnT (AUC 0.79 versus 0.80). Using a cut-off value of 4.0 ng/ml for H-FABP, sensitivity for ACS of the H-FABP (hs-cTnT) tests was 73.9% (70.6%). Negative predictive value (NPV) of H-FABP for ACS in a population representative for primary care (incidence of ACS 22%) thus could reach 90.8%.


CONCLUSIONS
In patients presenting chest pain, plasma H-FABP reaches the highest diagnostic value when a cut-off value of 4 ng/ml is used. Diagnostic values of an algorithm combining point-of-care H-FABP measurement and a score of signs and symptoms should be studied in primary care, to learn if such an algorithm could safely reduce referral rate by GPs.
a Department of Family Medicine , Maastricht University , Maastricht , the Netherlands.
Robert T A
RT
Willemsen
b Department of General Practice , Catholic University Leuven , Leuven , Belgium.
Evie
E
van Severen
c Department of Cardiology , Hospital Oost-Limburg , Genk , Belgium.
Pieter M
PM
Vandervoort
c Department of Cardiology , Hospital Oost-Limburg , Genk , Belgium.
Lars
L
Grieten
a Department of Family Medicine , Maastricht University , Maastricht , the Netherlands.|b Department of General Practice , Catholic University Leuven , Leuven , Belgium.
Frank
F
Buntinx
d Department of Genetics & Cell Biology , Maastricht University , Maastricht , the Netherlands.
Jan F C
JF
Glatz
a Department of Family Medicine , Maastricht University , Maastricht , the Netherlands.
Geert Jan
GJ
Dinant
D054058:Acute Coronary Syndrome / Q000097:blood* / Q000175:diagnosis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002637:Chest Pain / Q000209:etiology; D003430:Cross-Sectional Studies; D004636:Emergency Service, Hospital; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019095:Point-of-Care Systems; D011237:Predictive Value of Tests; D011320:Primary Health Care; D012372:ROC Curve; D020107:Troponin T / Q000097:blood*
C493408:FABP3 protein, human; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins; D020107:Troponin T
Acute coronary syndrome; early diagnosis; heart-type fatty acid binding protein; point-of-care systems; referral