الفهرس | Only 14 pages are availabe for public view |
Abstract The most commonly used measure of the systolic function of the left ventricle (LV) is ejection fraction (EF). EF is the ratio between the stroke volume and the end-diastolic volume. In cases of decreased systolic function but maintained stroke volume, due to the compensatory dilatation of the ventricle, a decreased EF reveals the dysfunction. However, in many cases, EF is probably a rather insensitive index of the LV function (Wandt et al, 2004). In healthy subjects, the EF tends to increase with advancing age, while it is not believed that the systolic pump function is increased. The reason is probably a thickening of the LV walls which causes decreased diastolic and systolic inner diameters and end-diastolic volume. It is also well known that the EF for the same reason is often preserved even in advanced cases of hypertension and hypertrophic cardiomyopathy with thickening of LV walls. In these cases (advanced age, hypertension, and hypertrophic cardiomyopathy), however, echocardiographic M-mode recording of the mitral annulus motion has shown that the longitudinal contraction of the ventricle is affected (Port et al, 1980), (Pfisterer et al, 1985). During recent years, the Maximal Longitudinal Contraction Velocity (MLCV), measured by tissue Doppler, has also been suggested as an index of systolic function (Gulati et al, 1996) and it has been used in patients with hypertension or hypertrophic cardiomyopathy, in patients with coronary heart disease (Vinereanu et al, 2002), in patients with amyloidosis, and in asymptomatic patients with severe aortic regurgitation (Vinereanu et al, 2001). However, there are no reports so far regarding the usefulness of MLCV in unselected patients with suspected or known systolic dysfunction (Wandt et al, 2004). The aim of this study is therefore to evaluate pulsed tissue Doppler in assessment of MLCV as a measure of LV systolic function in patients with systolic dysfunction. Aim of the Work: The aim of this study is to evaluate pulsed tissue Doppler in assessment of Maximal Longitudinal Contraction Velocity as a measure of LV systolic function in patients with impaired systolic function. |