The Research Of Evaluation Of Lower Limb Vascular Lesion In Type 2 Diabetic Patients By Using ET Technique And Its Related Risk Factors

Objective: Diabetes is a very common disease that causes multiple morbidity. The incidence for type 2 diabetes mellitus (T2DM) is 1.00% in 1979s and 3.21% in 1996s. There were 1.5 billion T2DM patients in the year 2000 in the world. And the incidence of T2DM in China is still continue increasing. The prognosis of T2DM depends on its chronic complications instead of itself. There are multiple chronic complications for T2DM which can cause mortality and morbidity. One of these complications is the lower extremity blood vascular lesion(LEBV), which can decreases the quantity of life and shorten the life span. It is very important to find LEBV of T2DM early for better prognosis. The traditional way of diagnosing the early changes of atherosclerosis by ultrasonic imaging is to measure the intima-media thickness(IMT), which is a morphological test. The goal of this study is to find a more reliable method to predicate the early functional change of the arteries before any morphological change by measuring the elasticity of the arteries in T2DM patients.Methods: The study included 68 patients with type 2 diabetes in the fourth Hospital of Hebei Medical University between Dec. 2007 and Oct. 2008. Thirty healthy people were included as the normal control group.The common femoral artery, superficial femoral artery, popliteal artery, posterior tibial artery, anterior tibial artery and dorsal pedal artery were tested by ALOKAα-10 ultrasound diagnostic apparatus. The inner diameter of the artery, the intima-media thickness(IMT), the peak forward velocity in systole, the reverse velocity in early-diastole, the velocity in end-diastole, the resistance index and the pulsatility index in lower limbs were measured. The number of atherosclerotic plague, extent of the stenosis were also recorded at the same time.With e-tracking(ET) techniques, the stiffness parameterβ, pressure-strain elasticity modulus (Eρ), arterial compliance (AC), argumentation index(AI) and one-point pulse wave velocity(PWVβ) of common femoral artery and popliteal artery were measured. The parameters were compared with control groups.The correlation of ET parameters with the IMT, stages of T2DM, age, systolic blood pressure(SBP) and blood lipid parameters were analyzed. For the IMT study, all the patients were divided into 2 groups based on the IMT of two sides of femoral arteries with one group IMT less than 1.0 mm, the other group more than 1.0mm. We compared the ET parameters of these two groups with the control group individually.For the effect of stages of T2DM, age, blood pressure and blood lipid parameters on the ET parameters, the patients were also divided into different groups and the correlation with the ET parameters were analyzed.Results: 1 In T2DM group, arterial wall became thick, rough and rigid. The atherosclerotic plagues were found inside artery wall in patients'group. The incidence of lower extremity atherosclerotic plague, arterial stenosis and obliteration of diabetes is apparently higher than that of control group(15.7%vs1.7%).2 The IMT of lower limb arteries in patients with T2DM are significantly thicker than in control groups(P <0.05). The IMT of femoral arteries and popliteal arteries in the two groups are positively correlated with age.3 The ET parameterβ, Eρ, PWVβof femoral arteries and popliteal arteries in patients with T2DM are significantly higher than in control groups. And AC was significantly lower( P <0.05).4β, Eρand PWVβof femoral arteries were significantly higher(P <0.05) and AC was significantly lower (P <0.05) in the groups that IMT≥1.0 mm and IMT<1.0 mm than those in the control group.β, Eρand PWVβof femoral arteries were significantly higher(P <0.05) in the group that IMT≥1.0 mm than those in the group that IMT<1.0 mm.5β, Eρand PWVβof femoral arteries were significantly higher(P <0.05) and AC was significantly lower ( P <0.05) both in the T2DM patients who were diagnosed the first time in our hospital and the T2DM patients who were diagnosed for a long time than in the control group.6β,Eρ,PWVβ,AC of femoral arteries and popliteal arteries in patients with T2DM and in control group were associated with age very well.7βof femoral arteries and popliteal arteries in control group and in patients with T2DM were significantly highly of who were older than 40 years than who were younger than 40 years.8βof femoral arteries and popliteal arteries in control group and in patients with T2DM were positively correlated with systolic blood pressure (SBP) and pulsatile blood pressure(PBP).9βof femoral arteries in patients with T2DM was positively correlated with total triglyceride(TG), low density lipoprotein(LDL), ApoB and ipoprotein(a)(Lpa).βof popliteal arteries had no significantly correlation with blood lipid parameters.10 In multiple liner regression,age,SBP,TG were risk factors ofβof femoral arteries in patients with T2DM( P <0.05). SBP was risk factor ofβof popliteal arteries in patients with T2DM( P <0.05).Conclusions: The color Doppler ultrasound can not only locate the exact spot and extent of the pathological changes of lower limb vascular lesion in patients with T2DM, but also provide diagnosis evidence for those without early stage symptoms. Femoral IMT is a marker for an early phase of the atherosclerotic process. IMT increase is consistent with the increase of age. The elasticity of femoral and popliteal arteries both decrease in patients with T2DM. There are femoral atherosclerotic changes in patients with type 2 diabetes. And the elasticity of femoral arteries decrease before the morphological changes. Duration of T2DM, age, SBP, PBP, TG and LDL are the risk factors of elasticity changes of femoral arteries in patients with T2DM. So it is very important to control blood pressure and blood lipid in patients with T2DM.