B-type natriuretic peptide and clinical judgment in the detection of exercise-induced myocardial ischemia.
BACKGROUND
Myocardial ischemia has been shown to be associated with increased levels of B-type natriuretic peptide (BNP). However, it remains unclear whether and how BNP levels could be used clinically in patients with suspected exercise-induced myocardial ischemia.


METHODS
We enrolled 274 consecutive patients with suspected exercise-induced myocardial ischemia referred for evaluation by rest/bicycle myocardial perfusion single-photon emission computed tomography (SPECT). All clinical information available to the treating cardiologist was used to quantify the clinical judgment regarding the presence of myocardial ischemia using a visual analogue scale twice: once before and once after bicycle exercise stress testing. BNP measurements were obtained before, immediately after, and 2 hours after stress testing in a blinded manner. The presence of myocardial ischemia was adjudicated on the basis of perfusion SPECT combined with coronary angiography findings.


RESULTS
Exercise-induced myocardial ischemia was adjudicated to be present in 103 patients (38%). BNP levels were significantly higher at all time points in patients with myocardial ischemia compared with those without (P < .01 for all). The accuracy of BNP levels as quantified by the area under the receiver operating characteristic curve (AUC) was similar among the time points evaluated (AUC, 0.677-0.697). Combining clinical judgment before exercise testing with BNP levels at rest increased diagnostic accuracy from AUC 0.708 to 0.754 (P = .018). When combining clinical judgment after exercise testing with BNP levels, AUC increased from 0.741 to 0.771 (P = .055).


CONCLUSIONS
Combining clinical judgment with BNP levels increased the diagnostic accuracy regarding the presence of myocardial ischemia.
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Gino
G
Lee
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland; Department of Internal Medicine, University Hospital Basel, Switzerland.
Seoung Mann
SM
Sou
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland; Department of Internal Medicine, University Hospital Basel, Switzerland.
Raphael
R
Twerenbold
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Tobias
T
Reichlin
Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Shino
S
Oshima
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland; Department of Internal Medicine, University Hospital Basel, Switzerland.
Thomas
T
Hochgruber
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Stephan
S
Zürcher
Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Deborah
D
Matter
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Yunus
Y
Tanglay
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Michael
M
Freese
Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Ursina
U
Honegger
Division of Nuclear Medicine, University Hospital Basel, Switzerland.
Damian
D
Wild
Department of Laboratory Medicine, University Hospital Basel, Switzerland.
Katharina
K
Rentsch
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Stefan
S
Osswald
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
Michael J
MJ
Zellweger
Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland. Electronic address: christian.mueller@usb.ch.
Christian
C
Mueller
D000368:Aged; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D003324:Coronary Artery Disease / Q000097:blood / Q000150:complications* / Q000175:diagnosis; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood* / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D015899:Tomography, Emission-Computed, Single-Photon
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain
B-type natriuretic peptide; Exercise electrocardiography; Myocardial ischemia; Single-photon emission computed tomography