QUANTITATIVE ASSESSMENT OF DIASTOLIC VENTRICULAR FUNCTION WITH TISSUE DOPPLER IMAGING AFTER FONTAN TYPE OF OPERATION

The aim of this study was to assess ventricular systolic and diastolic function after the Fontan procedure. 14 postoperative patients (pts) aged 12-31 years were prospectively evaluated with two-dimensional echocardiography equipped with tissue Doppler imaging capabilities (TDI) capabilities. 10 age-matched normal subjects were selected as controls. 5 pts (group 1) had LV systolic dysfunction (LV ejection fraction < 50%), 9 pts (group 2) had normal LV systolic function. Peak mean systolic (S) and diastolic (E,A) wall velocities were acquired from the 4-chamber view in the myocardia (septum -IVS- and free wall -FW-). TDI wall velocities during systole (Sa), early relaxation (Ea) and atrial systole (Aa) were also measured in the mitral annulus. Satisfactory TDI data could be obtained in all pts, independent of quality of LV wall motion. Compared to controls, group “1” pts had lower mean FW velocities (S=5.6 +/- 1.8 vs 8.4 +/- 2.1 cm/s – p<0.005 –; E=5.9 +/- 1.8 vs 9.3 +/- 2.4 cm/s – p< 0.001 –; A= 0 3.5 +/- 1.4 vs 3.6 +/- 1.8 cm/s – p=NS –) and lower annulus velocities both in systole and diastole (Sa =5.4 +/- 1.3 vs 8.7 +/- 1.5 cm/s – p<0.001 – ; Ea = 6.3 +/- 2.1 vs 13.3 +/- 2.4 cm/s – p< 0.001 – ; A = 7.9 +/- 2.2 vs 7.2 +/- 2.1 cm/s – p=NS – ). Also, group “1” pts had lower mean FW S and E velocities compared to IVS wall velocities (p < 0.005). Group “2” pts had preserved systolic velocities but decreased regional and annular early diastolic velocities suggesting impaired relaxation (Ea/Aa 0.88 +/- 0.26 vs 1.61 +/- 0.35 – p<0.0001 – ). These diastolic filling abnormalities in the presence of a normal or nearly normal ventricular ejection fraction suggest impaired ventricular relaxation. This in turn may influence pulmonary blood flow and cardiac output in pts after the Fontan operation.