الفهرس | Only 14 pages are availabe for public view |
Abstract Accurate assessment of left ventricular (LV) ejection fraction by two-dimensional transthoracic echocardiography (TTE) is time-intensive and limited by poor image quality, because of its dependence on endocardial tracing. The recognition of these limitations has led to the development of alternative echocardiographic methods for the assessment of LV systolic function. One proposed method involves the use of mitral annular displacement (MAD), which is fast and does not depend on endocardial definition and thus can be easily performed in the majority of patients quiet independent of imaging quality. (3,112,134) Thus, use of MAPSE measurement is helpful to evaluate LV systolic function in case of poor sonographic windows. MAPSE has been proposed as a well-established clinically useful echocardiographic parameter for the assessment of LV longitudinal function and correlates with global systolic function of the LV. Previous clinical studies showed that, MAPSE, which reflects the mitral ring displacement at systole, can be used to assess cardiac global longitudinal function and is a sensitive parameter to define slight abnormalities in various patients with cardiovascular diseases at early stage where longitudinal function is affected before other components of the heart. (84,85) Different studies tried to generate formula to predict ejection fraction from measuring MAPSE which corresponds to the systolic function of left ventricle either related to age, body surface area in pediatrics or gender. In 2012 Matos et al. generated gender specific formula to calculate ejection fraction using MAPSE where EF equals for men= 4.8 x MAPSE (mm) + 5.8 and for women= 4.2 x MAPSE (mm) + 20 compared with expert eyeball echocardiographer. (133) This study showed that MAPSE is an easy applicable method to measure with no significant intraobserver and interobserver variability. In this study which showed that mean value of average MAPSE was < 6 mm and mean value of lateral MAPSE was < 8 mm and mean value of med MAPSE was < 5 mm was linked with reduced values of ejection fraction (< 50%). In this study there was high significant correlation between ejection fraction measured using MAPSE in the gender specific formula generated by Matos et al. and ejection fraction measured by standard methods of echocardiography (M-mode, Simpson’s method, Eye ball method) in total patients and in male patients while there was non-significant correlation in ejection fraction measured by MAPSE compared to ejection fraction measured by M-mode, eye ball and Simpson’s in female patients. This study showed that female predicted ejection fractions using MAPSE formula generated by Matos et al. gave higher mean values than the mean values of ejection fraction measured by M-mode, Simpson’s method and eye ball. Using the patient population statistical data included in this study, another corresponding formula generated for both males and females to calculate ejection fraction by MAPSE for trial to reach a more accurate and reliable formula for predicting ejection fraction and for males predicted formula was; EF= 12.092 + 2.95 X average MAPSE (mm) and for females predicted formula was; EF = 26.334 + 0.944 X average MAPSE (mm). This study was conducted on patients with LV dysfunction due to different etiologies and both patients with ischemic or non ischemic LV dysfunction were enrolled in this study. MAPSE measurement is known to have less accurate readings in patients who have Regional wall motion abnormalities involving the base or mid-ventricle which would likely cause reduced annular motion locally and therefore may affect the estimation of overall EF. It should be noted that the wall motion abnormalities which involve the apex rather than the base of the heart will be less affecting the MAPSE estimation. Therefore, the results of this study cannot be extrapolated to patients with regional wall motion abnormalities involving the base and mid-ventricle. Similarly, we did not study patients with paradoxical septal wall motion which might affect the septal MAPSE (medial MAPSE). (137) In the End Although MAPSE has some limitations but it has a lot of clinical applications and implications in many cardiovascular diseases as hypertensive heart diseases, coronary artery diseases, aortic stenosis and heart failure. Also MAPSE is used as a tool or method to assess for prognosis and follow up in patients with myocardial infarction and for mortality follow up in patients with cardiomyopathy. (127,128,129) |