Interaction between right atrial function reserve and liver stiffness after complete repair of tetralogy of fallot: a pilot study

Abstract Background Impaired right atrial mechanics is reported in patients with repaired tetralogy of Fallot (TOF) and is associated with liver stiffness. However, whether right atrial functional reserve correlates with liver stiffness is unknown. Purpose This study tested the hypothesis that right atrial reserve capacity is limited in patients with repaired TOF and explore its relationships with right ventricular function and liver stiffness. Methods 10 patients (45% male) aged 19.04 ± 3.76 at 16.70 ± 4.30 years after repair and 15 controls (60% male, aged 20.31 ± 1.25 years) were studied. RA mechanics was assessed by speckle-tracking echocardiography (STE) at rest and during bicycle exercise, with quantification of positive, negative, and total strain, and strain rates at ventricular systole (aSRs), early diastole (aSRed), and atrial contraction (aSRac). Right atrial function reserve (RAFR) is calculated as (∆RA total strain x [1-1/ RA total strain at baseline]). RV systolic and diastolic function was quantified using Doppler interrogation and STE. Hepatic shear wave velocity (c) and tissue elasticity (E) were measured using two-dimensional shear wave elastography. Results At rest, patients had significantly lower RA positive, negative and total strain, aSRs and aSRed than control subjects (all P<0.02). Shear wave velocity and hepatic E value were significantly higher in patients than controls (both P<0.02). Compared with controls, patients had significantly lower RA positive, negative and total strain, aSRs, aSRed, and aSRac at exercise (all P<0.05). No significant difference in hepatic shear wave velocity and tissue elasticity were found between patients and control subjects at exercise (all P>0.05). Both baseline liver stiffness indices correlated negatively with RAFR, RA positive and total strain and aSRed at exercise (p<0.05 for all). RV function parameters, including baseline trans-tricuspid early and late diastolic inflow velocity (E, A), systolic, early and late diastolic tricuspid annular velocity (s, e, a), isovolumetric acceleration (IVA), RV systolic and diastolic reserve correlated significantly with RA positive and total strain at exercise (P<0.05 for all). Conclusions In young adults with repaired TOF, right atrial function reserve is impaired, and is associated with increased liver stiffness and RV dysfunction.RA mechanics from rest to exerciseStress RA mechanics and liver stiffness