Atrial aspiration from pulmonary and caval veins is caused by ventricular contraction and secures 70% of the total stroke volume independent of resting heart rate and heart size.
Clin Physiol Funct Imaging
; 33(3): 233-40, 2013 May.
Article
em En
| MEDLINE
| ID: mdl-23522018
ABSTRACT
BACKGROUND:
Whereas ventricular filling has been extensively studied and debated, atrial filling is less well characterized. Therefore, the aim of this study was to quantify atrial filling secured during ventricular diastole and systole, and to investigate whether atrial filling depends on heart rate (HR) and total heart volume (THV).METHODS:
Thirty-two athletes (16 women) and 32 normal subjects (16 women) underwent cardiac magnetic resonance imaging. Cardiac volumes and atrioventricular plane displacement (AVPD) were determined. Longitudinal and radial contribution to stroke volume was calculated using planimetry and used to determine diastolic and systolic atrial filling.RESULTS:
Atrial filling during ventricular diastole was 29 ± 10% of the total stroke volume, and during ventricular systole atrial filling was 68 ± 8% of the total stroke volume. There were no differences between groups of different HR (P = 0·70 and P = 0·41 for diastolic and systolic filling, respectively) or THV (P = 0·44 and P = 0·46 for diastolic and systolic filling, respectively). Systolic atrial filling was strongly correlated to longitudinal ventricular pumping (R = 0·76, P<0·001).CONCLUSION:
This study demonstrated that in healthy humans at rest, approximately 30% of the total stroke volume enters the atria during ventricular diastole and approximately 70% during systole, independent of heart rate (HR) or heart size. The atria are filled through suction driven by ventricular longitudinal contraction which aspirates blood from the pulmonary and caval veins. As 70% of the atrial filling occurs during ventricular emptying, the heart volume remains relatively constant over the cardiac cycle, which minimizes pulling on surrounding tissues and therefore optimizes energy expenditure.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Veias Pulmonares
/
Volume Sistólico
/
Veia Cava Inferior
/
Veia Cava Superior
/
Função Atrial
/
Função Ventricular
/
Cardiomegalia Induzida por Exercícios
/
Frequência Cardíaca
/
Contração Miocárdica
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
Clin Physiol Funct Imaging
Assunto da revista:
FISIOLOGIA
/
PATOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Suécia