title: Timing of Dynamic NT-proBNP and hs-cTnT Response to Exercise Challenge in Asymptomatic Children with Moderate Aortic Valve Regurgitation or Moderate Aortic Valve Stenosis.
abstract: Patients with congenital aortic valve stenosis (AVS) can remain asymptomatic but may develop progressive and often underestimated exercise intolerance. The risk of increased left ventricular (LV) wall stress, irreversible myocardial fibrosis and sudden death in untreated patients warrants earlier intervention. The timing for curative therapy for severe AVS is clear, but optimal timing for moderate stenosis (modAS) is unknown. AVS often coexists with aortic regurgitation, which adds a volume overload to an already pressure-overloaded LV, adding an additional challenge to the estimation of disease severity. We investigated the possible value of N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) upon treadmill exercise challenge in children with asymptomatic modAS versus moderate regurgitation (modAR). The aim was to determine optimal timing of peak biochemical response. Blood samples were obtained at rest, and then at 20, 40 and 60 min after peak exercise comparing modAS and modAR to healthy controls. Exercise performance was equivalent in all groups, with no difference for biomarker levels at rest. The increase in NT-proBNP was significant in modAR at 40 min (99.2 ± 48.6 ng/L; p = 0.04) and 60 min into recovery (100.0 ± 53.7 ng/L; p = 0.01), but not in modAS. The increase in hs-cTnT was significant only at 60 min into recovery for modAS and modAR. NT-proBNP and hs-cTnT following exercise challenge are possible discriminant biomarkers of modAR from modAS and controls at 60 min into recovery despite comparable exercise performance. This offers a promising avenue for future stratification of aortic valve disease and optimal timing of intervention.
authors.affiliation: Division of Pediatric Cardiology, CHU Sainte-Justine, University of Montreal, 3175, Cote Sainte-Catherine, Montréal, QC, H3T 1C5, Canada.
authors.forename: Wadi
authors.initials: W
authors.lastname: Mawad
authors.affiliation: Division of Pediatric Cardiology, CHU Sainte-Justine, University of Montreal, 3175, Cote Sainte-Catherine, Montréal, QC, H3T 1C5, Canada.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Abadir
authors.affiliation: Division of Pediatric Cardiology, CHU Sainte-Justine, University of Montreal, 3175, Cote Sainte-Catherine, Montréal, QC, H3T 1C5, Canada.
authors.forename: Anne
authors.initials: A
authors.lastname: Fournier
authors.affiliation: Division of Pediatric Cardiology, CHU Sainte-Justine, University of Montreal, 3175, Cote Sainte-Catherine, Montréal, QC, H3T 1C5, Canada.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Bigras
authors.affiliation: Department of Kinesiology, University of Montréal, Montréal, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Curnier
authors.affiliation: Mechanical and Industrial Engineering Department, Concordia University, Montréal, QC, Canada.
authors.forename: Lyes
authors.initials: L
authors.lastname: Kadem
authors.affiliation: Division of Pediatric Cardiology, CHU Sainte-Justine, University of Montreal, 3175, Cote Sainte-Catherine, Montréal, QC, H3T 1C5, Canada. nagib.dahdah.hsj@ssss.gouv.qc.ca.
authors.forename: Nagib
authors.initials: N
authors.lastname: Dahdah
mesh_terms: D000293:Adolescent; D001022:Aortic Valve Insufficiency / Q000097:blood*; D001024:Aortic Valve Stenosis / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002648:Child; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Aortic regurgitation; Aortic stenosis; Aortic valve disease; Biomarker; High-sensitivity cardiac troponin T; NT-proBNP; Treadmill testing; hs-cTnT