Assessment Of Aortic Different Segments Elasticity In Normal And Patient With Hypertension By Quantitative Tissue Doppler

Object:Currently, the evaluation to the research of the aorta elasticity with the application of the Quantitative Tissue Doppler technology is mainly performed via the parasternal long axis view. The success rate of sampling is rather low because of the effects of angle, noise and other factors; there is large variability and larger amount of samples is needed, therefore, it is a bit restricted in the clinical application. What is more, all the research have only performed the sampling analysis of single section (For instance,3cm at aortic valves); it only shows the elasticity of a certain section of the aorta, the multi-section sampling analysis hasn't be performed, therefore, it can't totally reflect the rules of elasticity variation of multi sections on the aorta. This research will show apical long axis view of aorta to evaluation aortic different segments elasticity in normal and patient with hypertension. On one hand, it will discuss the effect of the pathological factor of hypertension to the elasticity of aorta, then, it will research the characters of the variation of the aorta elasticity of the normal persons and hypertension patients along with the changes of ages; finally, it will analyze the relative index values of the elasticity of the aorta in multi section and it will primarily analyze the elasticity characters of different segments of the aorta. On the other hand, via the research by apical long axis view of aorta, we will perform the comparison analysis to the sampling of the parasternal long axis view to discuss the superiority of the longitude axle section sampling of apex cordis. It will provide the new methods for the evaluation of the main artery elasticity under different pathologic status such as hypertension, and it will also provide the rationale for the initial prediction and supervision of the changes of the main artery variation. Methods:105 cases of diagnosed hypertension patients have been collected in Body Examination Center of the 4th Affiliated Hospital of Kunming Medical College, and there are 81 cases with reliable information after research. The age range of the candidates is 30-80 and the average age is 55; among them, there are 31 male cases with the age range of 33-80 and the average age is 56; there are 50 female cases with the age range of 30-78 and the average age is 54. All the patients accepting examination will be grouped in 2 groups by their age:Group N1,30-60 years old,40 cases, the average age is 51; Group N2:60-80 years old 41 cases, the average age is 67. At the same time,81 cases of normal person have been collected in Body Examination Center of the 4th Affiliated Hospital of Kunming Medical College, and there are 72 cases with reliable information after research. The age range of the candidates is 30-80 and the average age is 59; among them, there are 37 male cases with the age range of 36-80 and the average age is 57; there are 35 female cases with the age range of 30-78 and the average age is 61. All the patients accepting examination will be grouped in 2 groups by their age:Group N1,30-60 years old,42 cases, the average age is 47; Group N2:60-80 years old,30 cases, the average age is 67. Vivid 7 color ultrasonic diagnose instrument produced by GE corporation is used; apical long axis view of aorta is taken and the section of aorta is shown; place the sampling point at the aortic ring and root part of the main artery, as well as 5cm above the aortic valve, we can get the velocity curves of early diastolic(Ve), atrial contraction(Va), and systolic(Vs) so as to reflect the elasticity characters of the systole and diastole of the aorta at different segments of the normal person and hypertension patients.Results:1. There are the obvious differences among the the total number (N) of three sections of the aorta (Aorta ring, root segment, far-end) among the hypertension group and comparison group(P<0.05), and the velocity of systolic(S) and early diastolic(E) the hypertension patients are obviously lower than that of the comparison group. The velocity of atrial contraction(A) has no significant difference with the comparison group (P>0.05), but its E/A value has the obvious differences(P<0.05), the hypertension patients are obviously lower than that of the comparison group. Among them, There are the obvious differences among Group N1 and Group N2 of three sections of the aorta (Aorta ring, root segment, far-end) among the hypertension group and comparison group(P<0.05), the velocity of systolic(S) and early diastolic(E) the hypertension patients are obviously lower than that of the comparison group. the velocity of atrial contraction(A) has no significant difference with the comparison group (P>0.05), but its E/A value has the obvious differences(P<0.05), the hypertension patients are obviously lower than that of the comparison group.2. There are the obvious differences among the normal Group N1 and Group N2 in terms of the velocity of systolic(S) and early diastolic(E) in three different segments (P＜0.05); there is the obvious difference between the aortic ring and the root part (P1<0.05), there are obvious differences between the aortic ring and the far end of the aorta (P2<0.05) and there is the obvious difference between the root part of the aorta and the far end (P3<0.05). Among them, Among them, the root part of the aorta has the largest velocity, the velocity at the aortic ring is lower and the velocity at the far end is the lowest.There are the obvious differences among the normal Group N1 and Group N2 in terms of the velocity of atrial contraction(A) in three different sections (P<0.05), there is the obvious difference between the aortic ring and the root part (P1<0.05), there are no obvious differences between the aortic ring and the far end of the aorta (P2>0.05) and there is the obvious difference between the root part of the aorta and the far end (P3<0.05). Among them, the root part of the main artery has the largest velocity, which is obviously higher than that at the aortic ring and root part of the aorta, but there are no obvious differences on the movement velocity between the aortic ring and the far end.There are the obvious differences among the hypertension Group N1 and Group N2 in terms of the velocity of systolic(S) and early diastolic(E) in three different segments (P<0.05); there is the obvious difference between the aortic ring and the root part (P1<0.05), there are obvious differences between the aortic ring and the far end of the aorta (P2<0.05) and there is the obvious difference between the root part of the aorta and the far end (P3<0.05). Among them, Among them, the root part of the aorta has the largest velocity, the velocity at the aortic ring is lower and the velocity at the far end is the lowest.There are the obvious differences among the hypertension Group N1 and Group N2 in terms of the velocity of atrial contraction(A) in three different sections (P<0.05), there is the obvious difference between the aortic ring and the root part (P1＜0.05), there are no obvious differences between the aortic ring and the far end of the aorta (P2>0.05) and there is the obvious difference between the root part of the aorta and the far end (P3<0.05). Among them, the root part of the main artery has the largest velocity, which is obviously higher than that at the aortic ring and root part of the aorta, but there are no obvious differences on the movement velocity between the aortic ring and the far end.3. There are the obvious difference between the normal comparison group and the hypertension group in terms of the velocity of systolic(S) and early diastolic(E) in three different segments (Aortic ring, root segment and far-end) in two age groups (N1 and N2) (P<0.05), the velocity of Group N2 is obviously lower than that of Group N1 which is younger; there are no obvious differences between the two age sections (N1 and N2) in terms of the velocity of atrial contraction(A) (P>0.05), but there is the obvious difference on E/A value between N1 and N2 (P<0.05).At the aortic ring of the normal group group:the velocity of systolic(S) is negatively relative to age (r=-0.716, P<0.01), the velocity of early diastolic(E) is negatively relative to age (r=-0.730, P<0.01), E/A value is negatively relative to age (r=-0.584, P<0.01).At the root part of the main artery of the normal group:the velocity of systolic(S) is negatively relative to age (r=-0.796, P<0.01), early diastolic(E) is negatively relative to age (r=-0.676, P<0.01), E/A value is negatively relative to age (r=-0.589, P< 0.01).At the far end of the main artery of the normal group:the velocity of systolic(S) is negatively relative to age (r=-0.370, P<0.05), the velocity early diastolic(E) is negatively relative to age (r=-0.412, P<0.01), E/A value is negatively relative to age (r=-0.543, P<0.01).At the aortic ring of the the hypertension group:the velocity of systolic(S) is negatively relative to age (r=-0.489, P<0.01), the velocity of early diastolic(E) is negatively relative to age (r=-0.579, P<0.01), E/A value is negatively relative to age (r=-0.5014,P<0.01).At the root part of the main arteryof the hypertension group:the velocity of systolic(S) is negatively relative to age (r=-0.652, P<0.01), early diastolic(E) is negatively relative to age (r=-0.619, P<0.01), E/A value is negatively relative to age (r=-0.492, P<0.01).At the far end of the main artery of the hypertension group:the velocity of systolic(S) is negatively relative to age (r=-0.457, P<0.01), the velocity early diastolic(E) is negatively relative to age (r=-0.362, P<0.05), E/A value is negatively relative to age (r=-0.363, P<0.05).Conclusions:1. Reduced aortic S velocity and E velocity of aortic upper wall is associated with increased aortic stiffness. Elastic properties of the aorta can be assessed by direct measurement of the movements in the upper aortic wall with Quantitative Tissue Doppler.2 In patients with hypertension aortic stiffness increased when aortic S velocity and E velocity reduced, which indicates that the elasticity function of the aorta of the patient deteriorates.3. The elasticity function of the oarta deteriorates along with the age growth, which indicates that age is a definitive clinical factor for aortic stiffness.4. The movement velocity of the aorta different segments has its rules; the movement velocity at the root part is the largest, and the velocity at the aorta ring is lower and that at the far end is the lowest.5. Measuring the movement velocity of the wall of aorta with Quantitative Tissue Doppler have the advantages of being simple and direct, relatively few interfering factors and high feasibility.6. The apical long axis view has effectively overcome the effects of angle, and the curve is relatively stable; it has good repetitiveness, and the sampling success rate is higher than that of the parasternal long axis view, so it has large advantages comparing with the parasternal long axis view.