The evaluation of left ventricle stiffness index in patients suffering from hypertension

Abstract

Many diseases can produce cardiac overload, of these disease hypertension, valve disease congenital anomaly in addition to many other disease. One of the most common diseases causing left ventricle overload is hypertension. A long term hypertension can cause myocardium hypertrophy leading to changes in the cardiac contractility and reduced efficiency. The investigations were carried out using conventional echocardiography techniques in addition to the tissue Doppler imaging (TDI) from which many noninvasive measurements can be readily obtained. The study has involved the effect of hypertension on the myocardium stiffness index through the measurement of early diastolic filling (E) and the early velocity of lateral mitral annulus (E_a) from which left ventricle filling pressure can be obtained. Our aim was to investigate the changes in the myocardium index of diastolic stiffness using TDI for patients suffering from systemic hypertension. We studied 263 hypertensive patients (105 males and 158 females of average age of 54.07± 12.7) and 166 healthy subjects (age range 40.06± 12.8,53 males and 113 females) as a control group. Measurements were carried out using tissue Doppler imaging (TDI) of the mitral annulus in addition to other echocardiographic measurements for the assessment of  left ventricle end diastolic dimension (LVEDD), Doppler peak early (E) and late (A) diastolic filling velocities. Results reveal that mitral annular early diastolic velocity (E_a) measured by TDI, that (E_a) was significantly lower for the hypertensive group in comparison with the control group (E_a 9.81 ± 2.87 cm/s for hypertensive vs. 12.90 ± 2.395 cm/s for control  p value <0.001. Hypertensive group also showed a significantly higher mitral annular late diastolic velocity (Aa) in comparison with control group as Aa 11.21 ± 2.504 cm/s for hypertensive vs. 9.787 ±2.201cm/s for control, p value <0.001..  In conclusion, LV myocardial diastolic stiffness index is increased in hypertensive patients.