title: Relation of N-terminal pro B-type natriuretic peptide levels after symptom-limited exercise to baseline and ischemia levels.
abstract: Circulating levels of B-type natriuretic peptide (BNP) and the amino-terminal portion of the prohormone (NT-proBNP) have been reported to increase immediately after myocardial ischemia. The association between extent of exercise-induced myocardial ischemia measured using myocardial perfusion scintigraphy and the magnitude and time course of changes in NT-proBNP was studied. One hundred one patients underwent symptom-limited exercise myocardial perfusion scintigraphy. Myocardial ischemia was assessed semiquantitatively. Serum samples were obtained before the start of exercise (baseline), at maximal exercise, and every hour up to 6 hours after maximal exercise. Myocardial ischemia was present in 37 patients (37%). NT-proBNP rapidly increased during exercise (to 113%, interquartile range 104 to 144, and 118%, interquartile range 106 to 142, of baseline, respectively), with a second peak at 4 (141%, interquartile range 119 to 169) and 5 hours (136%, interquartile range 93 to 188), respectively. Absolute changes between NT-proBNP at baseline and at maximum exercise in patients with versus without ischemia were similar (median, 30 pg/ml, interquartile range 7 to 45 vs 15, interquartile range 4 to 46, respectively, p = 0.230), but absolute change between baseline and the secondary peak was higher in patients with ischemia than in patients without ischemia (median 64 pg/ml, interquartile range 32 to 172 vs 34, interquartile range 19 to 85, respectively, p = 0.024). In multivariate linear stepwise regression analysis of determinants of changes in NT-proBNP after exercise, baseline NT-proBNP was the only independent determinant of absolute changes at maximum exercise, whereas the presence of ischemia was not predictive. Baseline NT-proBNP, cystatin C, and end-systolic volume were independent determinants of the absolute increase to secondary peak levels. In conclusion, myocardial ischemia per se did not lead to additional increases in NT-proBNP within 6 hours after exercise.
authors.affiliation: Department of Cardiology, Academic Medical Center, Amsterdam, The Netherlands. p.m.vanderzee@amc.uva.nl
authors.forename: P Marc
authors.initials: PM
authors.lastname: van der Zee
authors.forename: Hein J
authors.initials: HJ
authors.lastname: Verberne
authors.forename: Rianne C
authors.initials: RC
authors.lastname: van Spijker
authors.forename: Jan P
authors.initials: JP
authors.lastname: van Straalen
authors.forename: Johan C
authors.initials: JC
authors.lastname: Fischer
authors.forename: Augueste
authors.initials: A
authors.lastname: Sturk
authors.forename: Berthe L F
authors.initials: BL
authors.lastname: van Eck-Smit
authors.forename: Robbert J
authors.initials: RJ
authors.lastname: de Winter
mesh_terms: D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood* / Q000000981:diagnostic imaging / Q000503:physiopathology; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain