Delayed release of brain natriuretic peptide to identify myocardial ischaemia.
BACKGROUND
A recent pilot study suggested that exercise-induced myocardial ischaemia may lead to a delayed release of cardiac biomarkers, so that later sampling, for example, at 4 h after exercise could be used for diagnostic purpose.


METHODS
In an observational study, we enrolled 129 consecutive patients referred for evaluation of a suspected coronary artery disease by rest/stress myocardial perfusion single-photon emission computed tomography. The treating cardiologist used all available clinical information to quantify clinical judgment regarding the presence of myocardial ischaemia using a visual analogue scale twice: prior and after stress testing. BNP levels were determined in a blinded fashion at rest, at peak stress and 4 h after peak stress. The presence of myocardial ischaemia was adjudicated based on perfusion single-photon emission computed tomography and coronary angiography findings by an independent cardiologist.


RESULTS
Myocardial ischaemia was detected in 58 patients (45%). Patients with myocardial ischaemia had significantly higher BNP levels at all times, compared to patients without ischaemia: BNP rest (99 vs. 61 pg/mL P = 0·007), BNP stress (125 vs. 77 pg/mL P = 0·02) and BNP 4 h (114 vs. 71 pg/mL P = 0·018). Diagnostic accuracy as quantified by the area under the receiver operating characteristics curve (AUC) was moderate for all time points (AUC 0·64-0·66). The change in BNP between rest and 4 h did not provide added value, neither to the baseline BNP level nor to clinical judgment.


CONCLUSIONS
In contrast to our hypothesis, myocardial ischaemia did not lead to a differential delayed release of BNP. Late sampling did not seem clinically useful.
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Stephan
S
Zürcher
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Ursina
U
Honegger
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Max
M
Wagener
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Gino
G
Lee
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Fabio
F
Stallone
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Tanja
T
Marxer
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Christian
C
Puelacher
Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Carmela
C
Schumacher
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.|Department of Internal Medicine, University Hospital Basel, Basel, Switzerland.
Seoung Mann
SM
Sou
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.|Department of Internal Medicine, University Hospital Basel, Basel, Switzerland.
Raphael
R
Twerenbold
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Tobias
T
Reichlin
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.|Department of Internal Medicine, University Hospital Basel, Basel, Switzerland.
Thomas
T
Hochgruber
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Yunus
Y
Tanglay
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Michael
M
Freese
Division of Nuclear Medicine, All at the University Hospital Basel, Basel, Switzerland.
Damian
D
Wild
Department of Laboratory Medicine, All at the University Hospital Basel, Basel, Switzerland.
Katharina
K
Rentsch
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Stefan
S
Osswald
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Michael
M
Zellweger
Department of Cardiology, University Hospital Basel, Basel, Switzerland.|Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Christian
C
Mueller
D000368:Aged; D019540:Area Under Curve; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000097:blood* / Q000175:diagnosis / Q000000981:diagnostic imaging; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood* / Q000175:diagnosis / Q000000981:diagnostic imaging; D055414:Myocardial Perfusion Imaging; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012372:ROC Curve; D013997:Time Factors
D020097:Natriuretic Peptide, Brain
Brain natriuretic peptide; exercise electrocardiography; myocardial ischaemia