The Influence of Atrial Strain on Functional Capacity in Patients with the Fontan Circulation

AbstractSpeckle-tracking echocardiography has been used to assess atrial function. This analysis is feasible in univentricular hearts. The aim of this study was to characterize the relationship between atrial strain and functional capacity in the Fontan circulation. Apical four-chamber echocardiographic loops of 39 Fontan patients were reviewed. The dominant atrium was assessed for active (εact), conduit (εcon), and reservoir (εres) strain andεact/εres ratio. Cardiopulmonary exercise test was performed on the same day and oxygen uptake (VO2) at ventilatory threshold (VT) and peak VO2 were chosen as the dependent variables. Statistical analysis was performed using SPSS® version 23. Unpairedt test was used for binomial and continuous variable correlation; single and multivariable linear regression were used for continuous variable correlation. Statistical significance was defined asp value  <  0.05. VO2 at VT as a percentage of predicted VO2 was 36.8% (SD 10.7). Peak VO2 was 64.7% (SD 18.9) of the predicted value. In univariate analysis, both were associated with age, atrioventricular regurgitation, ejection fraction,εres,εcon, andεact/εres. In multivariate regression, higher VO2 at VT and peak VO2 were associated with younger age (p = 0.003 andp = 0.001, respectively) and higherεcon (p = 0.026 andp = 0.020). Evaluation of heart function is difficult in the Fontan circulation, hindered by complex ventricular morphology and lack of normative data. VO2 pro...
Source: Mammalian Genome - Category: Genetics & Stem Cells Source Type: research