title: Usefulness of High-Sensitive Troponin Elevation After Effort Stress to Unveil Vulnerable Myocardium in Patients With Heart Failure.
abstract: Elevation of resting high-sensitivity troponin (hs-Tn) holds prognostic value in heart failure (HF), but its pathophysiological meaning is unclear. We aimed to investigate hs-Tn elevation after maximal exercise in patients with systolic HF and its neurohormonal and hemodynamic correlates: 30 patients diagnosed with systolic HF (left ventricular ejection fraction 32 ± 8%, mean ± SD), on guideline-directed medical therapy and not recognized inducible ischemia, underwent maximal cardiopulmonary stress test, with assay of plasma N-terminal proB-type natriuretic peptide (NT-proBNP), norepinephrine (NE), and hs-TnT (hs-TnT) at baseline, peak, and 1 and 4 hours after exercise. Cardiac output (CO) was measured during effort, with a rebreathing technique. The natural logarithm of the ratio between percentage (%) increase in CO and NT-proBNP (ln[CO%/NT-proBNP% increase]) was evaluated, as a noninvasive estimate of Frank-Starling adaptation to effort, with NT-proBNP variation considered as a surrogate of end-diastolic left ventricular pressure variation. Hs-TnT increased during exercise with a 4-hour peak (p = 0.001); 10 patients had hs-TnT increase >20%. Patients with Hs-TnT increase >20% were more symptomatic at rest (p = 0.039) and showed greater NE at peak exercise (p = 0.003) and less ln[CO%/NT-proBNP% increase] (p = 0.034). A lower ln[CO%/NT-proBNP% increase] correlated with greater NE at peak exercise (r = -0.430, p = 0.018). In conclusion, acute troponin elevation after maximal exercise was detected in 1/3 of this series. The association of troponin release with NE, CO, and NT-proBNP changes after effort suggests a pathophysiological link among transient hemodynamic overload, adrenergic activation, and myocardial cell damage, likely identifying a clinical subset at greater risk for HF progression.
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy; Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy. Electronic address: pastormerlo@ftgm.it.
authors.forename: Luigi Emilio
authors.initials: LE
authors.lastname: Pastormerlo
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy.
authors.forename: Assunta
authors.initials: A
authors.lastname: Agazio
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Benelli
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Gabutti
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Poletti
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy.
authors.forename: Concetta
authors.initials: C
authors.lastname: Prontera
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy; Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Clerico
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy; Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Emdin
authors.affiliation: Division of Cardiology and Cardiovascular Medicine, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy; Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Passino
mesh_terms: D000368:Aged; D002302:Cardiac Output / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D009638:Norepinephrine / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011237:Predictive Value of Tests; D011379:Prognosis; D012146:Rest / Q000502:physiology; D013997:Time Factors; D020107:Troponin T / Q000097:blood*; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D009638:Norepinephrine