The Study On Arterial Elasticity Of Atherosclerosis Patients With Echo Tracking Technique

Artherosclerosis (As) is a kind of basic pathological changes in morphology and function on arteries of lots of cardiovascular and cerebrovascular diseases. It shows thickening endarterium and atheromatous plaque in morphology, low vessel wall complaisance and high rigidity in function. It is difficult to diagnose how serious of As directly in clinic, so the common method of evaluating degree of AS is observing the changes of indexes on structure and function of artery vessels.Ultrasound technique can examine As in morphology, function and hemodynamics. The common indexes are the thickness of intima-media tunica (IMT) and the size of plaque. Pathology method has proved the correction of IMT measuring by Ultrasound technique, which is significant on diagnosing As in clinic. But, there is no uniform standard on examining method of IMT and different results in studies about it. There are no obvious changes on IMT during compensated vascular remodeling. IMT and the size of plaque do not reflect the function changes of As. IMT isn't thickening in some patients who showed As clinical symptom. On the contrary, IMT is thickening in some patients who didn't show As clinical symptom. Therefore,there are some limit in evaluating the degree of As with IMT and the size of plaque only.We are going to examine the indexes of arteries structure and elasticity to evaluate the changes of As , including IMT, the size of plaque, arteries rigidity degree, and so on. With observing the arteries elasticity indexes in different clinical symptom, we can evaluate the changes of the arteries elasticity As correctly, objectively, and widely. And that can provide the new data for studing function of blood vessel of As.We examined the indexes on structure and vessels elasticity of left and right carotid arteries and femoral arteries using ALOKA SSD-5500 ultrasonograph. We put 119 patients to three groups accoding to theirs data of US and clinic. Group A (normal control ): 31 normal adults, there are no plaque on carotid arteries and femoral arteries. Group B (As and no clinical symptom): 47 patients. there are plaques on carotid arteries and femoral arteries, but no clinical symptom of hypertension, diabetes, or coronary arteriosclerotic heart disease. Group C (As and have clinical symptom): 41 patients. There are plaques on carotid arteries and femoral arteries in 2D-ultrasonic method, at the same time, they have clinical symptom of hypertension, diabetes, or coronary arteriosclerotic heart disease. We made statistical analysis on the data of left carotid arteries and right femoral arteries.The results showed that there were no statistical differences (p>0.05) in the arteries elasticity indexes (Ep,β, AC) and the arteries morphology indexes between left carotid arteries and right femoral arteries in every groups, which suggest that there are the same processes in pathology and pathophysiology, and no statistical differences on the pathological changes degrees of carotid and femoral arteries during As developing. In the arteries elasticity indexes of carotid and femoral arteries, contrasting A group, we found that Ep andβwere increasing, but AC was decreasing in B group and C group. There were some statistical differences in the carotid arteries elasticity indexes: Ep andβwere more increased (p<0.01), but AC was more decreased (p<0.05) in C group than those in A group.βwas more increased (p<0.05) in C group than that in B group. There were some statistical differences in the femoral arteries elasticity indexes: Ep andβwere more increased (p<0.01), but AC was more decreased (p<0.05) in C group than those in A group. Ep was more increased (p<0.05) in C group than that in B group.The trial results suggest that the arteries elasticity in As patients is decreasing. The arteries elasticity reflects mainly the state of arteries diastolic function, and the function of which can not only explain the changes of systolic pressure, diastolic pressure,and pulse pressure, but also show the vessel function damage induced by many risk factors and the risk of cardiovascular deseases on some extent. It is significant of examining the arteries elasticity for monitoring As developing and evaluating the effect of drug treatment. For the decreased arteries elasticity, we can analyze the reasons in pathematology. Through the microscope, it is observed that the number of elastic fibers in tunica media of As vessel wall is decreased, the elastic membrane netted by is ruptured, collagen fibers are proliferative and collective in the mesh gaps of elastic fibers,the ratio of hypertrophic elastic fibers and collagen fibers are decreased obviously,smooth muscle cells in the elastic membrane lined in disorder, the connection is loose between fiber groundplasm and smooth muscle cells. In the final, the abnormal changes of arteries walls structure induce the arteries elasticity function decreasing. The results also showed that there were some relationships between arteries elasticity and clinical symptom in As patients, as the clinical symptom going, the arteries elasticity is decreased obviously. When As is going, the arteries walls become thickening, the lumen of blood vessel become narrow, which both make the blood flow volume decreased in arteries, and the relative clinical symptom happen with blood deficiency damage in organs or tissues. With the arteries elasticity developing seriously,the effect on blood volume of tissues and organs becom worse, which cause some relative deseases and symptom. Besides, we found that the more there is As plaque, the lower arteries elasticity function becomes . It is showed that the degree of As and the arteries elasticity decreasing is serious with the relative symptom and deseases happening, and with the rich plaques. Therefore, the level of arteries elasticity decreasing can be an index of reflecting the degree of As vasculopathy.Contrasting with old trials, the data included vessel elasticity indexes (Ep,β, and AC) and structure indexes (IMT and the size of plaque) of As patients in our trial, which make the evaluation widely on vessel pathological changes of As. The trial used the e-tracking technique to examine the changes of arteries elasticity on As patients, grouped them with different clinical symptom and medical records, and evaluated their arteries elasticity. The results provide some new data to study the relationship of arteries elasticity and clinical symptom. The e-tracking technique shows the changes of vessel internal diameter during systolic and diastolic phase,and calculates Ep,βand AC automaticly, which decreases error caused by human factor and makes the results accurate. The e-tracking technique can provide an important method on evaluating objectively the vasculopathy of As patients ,on directing clinic to interrupt therapeutic measure and on showing the treating effects, the method will play a significant role in clinic.