Evaluation of left ventricular relaxation and estimation of filling pressures by tissue doppler imaging

Doppler Left ventricular [LV] filling indices have been used to evaluate different parameters of diastolic function. However the- interpretation of these indices becomes challenging when several haemodynamic alterations occur simultaneously. Color M-mode and Doppler tissue imaging [DTI] have been shown to provide an accurate estimation of LV relaxation and appear to he relatively insensitive to the effect of preload compensation. The aim of this study was to assess the value of DTI the evaluation of LV relaxation and in the estimation of LV filling pressure among patients with coronary artery disease [CAD].We studied 30 patients with CAD and 10 normal control volunteers [6 males and 4 females; age 35.50 +/- 7.32 yrs]. The patients included 15 [45.80 +/- 9.67 yrs] with impaired relaxation [IR] and 15 [55.73 +/- 7.82 yrs] with pseudonormal relaxation pattern. Alt patients were subjected to conventional Doppler echocardiography to assess LV diastolic function by measurement of E and A waves and time E/A ratio]. For DTI, the following mitral valve annular velocities were measured: peak systolic velocity [Sa], early "Ea" and late "Aa" diastolic velocities, acceleration time of Ea [from onset to peak of Ea], deceleration time of' Ea [from peak to baseline] and the E/Ea [ratio of transmitral E to mitral annular E velocity]. LV catheterization was done to measure LV end-diastolic pressure [LVEDP] by fluid filled catheter. RV catheterization was done to measure pulmonary capillary wedge pressure [PCWP]. E/A ratio could not different between normal and groups. Both normal and pseudonormal groups displayed higher E wave 82.3 +/- 13.5 and 78.13 +/- 15.11, respectively and higher E/A ratio "1.3 +/- 0.12 and 1.9 +/- 0.3, respectively", compared to impaired relaxation group "E: 55.60 +/- 7.08, E/A ratio=0.68 +/- 0.12", Sa was significantly reduced in the pseudonormal group compared to the other 2 groups. Early diastolic annular velocity [Ea] was significantly lower in pseudonormal and impaired relaxation groups [5, 33 +/- 1.7 and 7.37 +/- 2.01] compared to normal group [14.70 +/- 3.3] [P< 0.001]. E/Ea ratio was significantly increased in pseudonormal group compared to the other 2 groups. There was good correlation between E/Ea and PCWP [PCWP = 1.29 [E/Ea] + 1.9.] There was a good relation between E/Ea ratio and LVEDP. The difference between catheter and Doppler-measured LVEDP was 0.1 +/- 3.8. In normal group. PCWP was 9.27 +/- 1.9 by DTI, 8.0 +/- 2.3 by catheter. In impaired relaxation group, PCWP was 11.20 +/- 2.4 by DTI, 10.47 +/- 3.23 by catheter. In pseudonormal group. PCWP was 21.93 +/- 8.5 by DTI, 21.80 +/- 6.91 by catheter. Early diastolic velocity of the mitral annulus "Ea" can distinguish a pseudonormal mitral inflow pattern from a normal one. E/Ea is an accurate method for estimation of LV filling pressures

Non invasive evaluation of patients with ventricular septal defect after surgical correction

The present work is planned to study the cause of any residual cardiac murmur after surgical closure of ventricular septal defect and to evaluate cardiac function using Doppler echocardiography. Twenty cases of isolated VSD who underwent trans-atrial surgical closure of VSD were studied. They were 14 males and 6 females. Their age ranged between 3 and 20 years with a mean of 8. 5 +/- 4 years. Preoperative data were collected from patients files as cardiac catheterization data. Operative details were recorded during operation. Post operative study was also conducted and included clinical examination for any residual cardiac murmur. ECG, chest X-ray and Doppler echocardiography were performed to assess closure of the defect. Patients were classified into two groups. Group I included 8 patients with RV pressure < 50 mm Hg. Group 2: included 12 patients with RV pressure > 50 mm Hg. Doppler examination revealed 14 cases of 20 [70%] proved to have no residual shunt. 4 cases had mild shunt [20%], 2 cases had moderate shunt [10%] and no case showed large shunt. The shunt occurred along the suture line. Left ventricular function was assessed by the EF% which ranged between 47% and 63%. RV pressure decreased significantly in both groups postoperatively, post operative echo evaluation has also showed that 9 patients had TR 45%, 1 patient had pericardial effusion [5%], 1 showed vegetation on the patch [5%] and I patient had right atrial thrombus [5%]. We conclude that Doppler echocardiography is highly sensitive in the early post operative detection of VSD shunt, as well as other postoperative complications as pericardial effusion, vegetation on the patch and myocardial dysfunction. Results showed also that RV pressure decreased significantly after closure of the defect in both groups, however, in patients with VSD and at least moderate pulmonary hypertension, pulmonary artery pressure was not returning to normal therefore, it is advisable to operate on individuals with VSD and moderate pulmonary hypertension before there is the any increase of pulmonary vascular resistance