Characterizing the influence of cardiorespiratory fitness on left atrial size and function in the general population.
Am J Physiol Heart Circ Physiol
; 326(5): H1269-H1278, 2024 May 01.
Article
em En
| MEDLINE
| ID: mdl-38457351
ABSTRACT
Increased left atrial (LA) size and reduced LA function have been associated with heart failure and atrial fibrillation (AF) in at-risk populations. However, atrial remodeling has also been associated with exercise training and the relationship between fitness, LA size, and function has not been defined across the fitness spectrum. In a cross-sectional study of 559 ostensibly healthy participants, comprising 304 males (mean age, 46 ± 20 yr) and 255 females (mean age, 47 ± 15 yr), we sought to define the relationship between cardiorespiratory fitness (CRF), LA size, and function. We also aimed to interrogate sex differences in atrial factors influencing CRF. Echocardiographic measures included biplane measures of LA volumes indexed to body surface area (LAVi) and atrial deformation using two-dimensional speckle tracking. CRF was measured as peak oxygen consumption (VÌo2peak) during cardiopulmonary exercise testing (CPET). Using multivariable regression, age, sex, weight, and LAVi (P < 0.001 for all) predicted VÌo2peak (P < 0.001, R2 = 0.66 for combined model). After accounting for these variables, heart rate reserve added strength to the model (P < 0.001, R2 = 0.74) but LA strain parameters did not predict VÌo2peak. These findings add important nuance to the perception that LA size is a marker of cardiac pathology. LA size should be considered in the context of fitness, and it is likely that the adverse prognostic associations of increased LA size may be confined to those with LA enlargement and low fitness.NEW & NOTEWORTHY Left atrial (LA) structure better predicts cardiorespiratory fitness (CRF) than LA function. LA function adds little statistical value to predictive models of peak oxygen uptake (VÌo2peak) in healthy individuals, suggesting limited discriminatory for CRF once LA size is factored. In the wider population of ostensibly healthy individuals, the association between increased LA volume and higher CRF provides an important counter to the association between atrial enlargement and heart failure symptoms in those with cardiac pathology.
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Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Função do Átrio Esquerdo
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Remodelamento Atrial
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Aptidão Cardiorrespiratória
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Átrios do Coração
Limite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Am J Physiol Heart Circ Physiol
Assunto da revista:
CARDIOLOGIA
/
FISIOLOGIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Austrália