Assessment of biventricular and vascular function using three-dimensional speckle tracking echocardiography in adult patients with surgical repair of tetralogy of Fallot

Background: In patients late after correction of Tetralogy of Fallot (TF) the combined effects of preoperative hypertrophy and hypoxia, possible intraoperative myocardial damage, type of reconstruction, acquired postoperative lesions such as pulmonary or aortic regurgitation, and congenital vasculopathy may result in impaired right ventricular (RV) as well as left ventricular (LV) function. We hypothesized that a comprehensive assessment of ventricular, aortic and pulmonary artery function could help to better understand the pathophysiology of this complex disease. Methods: Eighteen patients (mean age 37 ± 14 years) with repaired TF and eighteen age-matched healthy subjects selected as controls were studied. LV and RV longitudinal, circumferential, and radial strains were calculated by three-dimensional speckle tracking echocardiography (3DSTE). Global area strain (GAS) was obtained by 3DSTE as the percentage variation in the surface area defined by the longitudinal and circumferential strain vectors. Pulmonary artery (PA) and ascending aorta (Ao) stiffness and strain were determined using M-mode and speckle tracking echocardiography. Data analysis was performed offline. Results: Overall, Ao and PA stiffness were increased (p=0.0003) and Ao and PA strains were decreased (p=0.0002) in TF patients compared to controls. Stiffness index had a negative correlation with Ao (p<0.001) and PA (p<0.005) strain. Ao and PA strains correlated with LV and RV longitudinal strain (p<0.05 and p<0.01 respectively) and LV and RV area strain (p=0.02 and p<0.01 respectively). A significant correlation was found between PA stiffness and pulmonary regurgitant fraction and volume (p=0.004), and between Ao stiffness and aortic regurgitant fraction and volume (p<0.001). Conclusions: In patients with repaired TF increased PA and Ao stiffness are associated with reduced RV and LV 3DSTE parameters. Changes in PA and Ao stiffness and strain are more pronounced in the presence of pulmonary or aortic regurgitation and should be taken into account when evaluating post-operative TF.