Assessment of early diastolic intraventricular pressure gradient in the left ventricle among patients with repaired tetralogy of Fallot.

Assessment of left ventricular (LV) dysfunction is vital in patients with repaired tetralogy of Fallot (rTOF). The early diastolic intraventricular pressure gradient (IVPG) in the LV plays an important role in diastolic function. IVPG is calculated as the intraventricular pressure difference divided by the LV length, which allows to account for differences in LV size and therefore calculate IVPG in children. We aimed to investigate the mechanisms of LV diastolic dysfunction by measuring mid-to-apical IVPG as an indicator of the active suction force sucking blood from the left atrium into the LV. We included 38 rTOF patients and 101 healthy controls. The study population was stratified based on age group into children (4-9 years), adolescents (10-15 years), and adults (16-40 years). IVPGs were calculated based on mitral inflow measurements obtained using color M-mode Doppler echocardiography. Although total IVPGs did not differ between rTOF patients and controls, mid-to-apical IVPGs in adolescents and adults were smaller among rTOF patients than among controls (0.15 ± 0.05 vs. 0.21 ± 0.06 mmHg/cm, p < 0.05; 0.09 ± 0.07 vs. 0.17 ± 0.05 mmHg/cm, p < 0.001; respectively). Additionally, only mid-to-apical IVPG correlated linearly with peak circumferential strain (ρ = 0.217, p = 0.011), longitudinal strain (ρ = -0.231, p = 0.006), torsion (ρ = -0.200, p = 0.018), and untwisting rate in early diastole (ρ = -0.233, p = 0.006). In rTOF, the mechanisms underlying diastolic dysfunction involve reduced active suction force, which correlates with reduced LV deformation in all directions.

Non-invasive assessment of liver fibrosis in patients after the Fontan operation.

BACKGROUND: This study analyzed the change in liver fibrosis markers after the Fontan operation and investigated their clinical usefulness as an index of congestive liver fibrosis. METHODS: The study enrolled 24 patients who underwent the Fontan operation between January 1994 and December 2008. We subdivided the postoperative period into four intervals and then compared the hepatological markers during each. Eighteen patients underwent postoperative cardiac catheterization and the correlation between hepatological markers and the inferior vena cava (IVC) pressure was analyzed. RESULTS: The mean age of the patients was 138.6 months and the mean interval between the Fontan operation and the examination was 97.8 months. Type IV collagen was extremely high in every interval (I, 286 ± 93; II, 265 ± 93; III, 305 ± 143; IV, 206 ± 70), while none of the laboratory variables changed significantly in each interval. A significant positive correlation was observed between type IV collagen and the IVC pressure, but no significant correlation with any other hepatological marker was detected. CONCLUSIONS: No specific parameter that reflects the progress in liver fibrosis was identified in this study. The possibility exists that type IV collagen reflects the degree of hepatic congestion.