Study On Pathogenesy Of Arteriosclerosis In Aortoiliac Artery And Clinical Application Of Interventional Therapy

PrefaceArteriosclerosis (AS) is one of the most serious diseases that is harm to human body, which is common and frequent encountered. In recent years, the incidence of AS has had a tendency to increase dramatically all over the world. Study on AS has been on for many years but there are many questiones about AS having not been illuminated and there is not an integrated theory about its patho-genesy. Therefore, it is an important topic for domestic and foreign doctors to further explore pathogenesy and how to prevent postangioplasty restenosis.It has been proved that the formation and development of AS was the result of interaction between cells in vessel wall and growth factor and cytokine played important role during above process. Except for machanism of paracrine secretion outside of cells, recent study has showed another machanism that was direct communication between cells, ie gap junction, which may participate this kind of interaction. Gap junction is a kind of channal structure made up of membrane protein, which is the only cell junction that can mediate the communication of substance and information between cells. The main component to constitute gap junction is connexin, 16 kind of which have been found in mammal and Cx43 is the main protein of gap junction in cardiovascular system. It has been believed that expression and distribution abnormity of Cx43, leading to functional disturbance of gap junction, were relative with the formation and development of manykinds of cardiovascular system. Therefore, AS model of rabbits'aorto - iliac artery was established to examine the expression of Cx43 to explore the relation between expression of Cx43 and pathogenesy of AS and restenosis after balloon injure, which can provide theory foundation for pathogenesy of AS and interven-tional treatment of AS in clinic.Arteriosclerosis always locates in abdominal aorta inferior to renal artery, iliac artery and femoral artery. The ratio of male to female aged from 40 years to 70 years who suffered from arteriosclerosis is approximately 2 to 1. The clinical character of the disease is buttock and thighs muscle sour and pain, intermittent claudication in lower limb, rest pain, pulseless and changes of temperature and color of skin. Male patients may suffer from the sexual disturbance if the lesion covers bilateral inner iliac arteries. The main methods to deal with it in the past were vascular surgery of bridging operation, which have been restricted by many factors, so most of patients could not be treated. Recently, with the development of endovascular technology, interventional treatment has replaced surgeri-cal by - pass of aorta - iliac artery or aorta - femoral artery and showed satisfactory clinical efficacy and application prospect. But it is not confirmed how to choose the indicatio of AS in peripheral blood vessel and canalizing technique of occlusion part and how to prevent the restenosis postangioplasty. Therefore, it is helpful to consummate the clinical application of interventional technique for treatment of AS in peripheral blood vessel to deeply explore the technologic points of interventional treatment for occlusion of aorto - iliac artery and follow up and observe the mediate and long term efficacy after treatmemt of balloon dilation and stent insertion for this kind of disease.Methods and ResultsExperiment â…  . Study on Changes of Expression of Cx43 During theProcess of Atherosclerotic LesionMaterials and Methods1. animal model and groupsRandomize 50 healthy male rabbits (weight ranged from 2. 5 to 3. Okg) into four groups: control group was 5; high fat diet group was 15; balloon dilation group was 15 ; high fat diet and balloon dilation group was 15 , which were fed a-daptable for 1 week. Rabbits were respectively fed with common forage in control group and high fat forage (its component is 2% cholesterol and common forage ) in high fat diet group. Rabbits were respectively fed with common forage in balloon dilation group and high fat forage in high fat diet and balloon dilation group after balloon lesion of abdominal aorta and bilateral and iliac artery. 3 rabbits in each test group above were killed respectively at the NO. 1,2,4,6,8 week and 1 rabbit was killed in control group.2. Examination index were value of blood fat and ultraphonic Doppler, his-tological observation by light microscope, immunohistochemistry assay for expression of Cx43 and PCNA, Western blot assay of Cx43 and ultramicrostructure of subintimal lesion by transmission electron microscope.Results1. The value of TC, TG and LDL in high fat diet group and in high fat diet and balloon dilation group was all higher than those in control group and in balloon dilation group ( P <0. 01 ).2. The mean of every index in test group, including SV, MV and S/D, increased obviously except for DV( P <0. 05 ).3. In light microscope, that the intima became thicker was the main character in balloon dilation group and that the AS plaque appeared was the main character in high fat diet group and in high fat diet and balloon dilation group, especially in the later.4. Positive expression of Cx43 under intima showed cytoplasm was brown -yellow. Positive expression of Cx43 has the tendency to be stronger in high fat diet group. The A value of Positive expression of Cx43 hit the peak at the second week after artery lesion in balloon dilation group and became weaker in the following several weeks. The A value of Positive expression of Cx43 also hit thepeak at the second week after artery lesion in high fat diet and balloon dilation group and decreased gradually, which increased again from the sixth to the eighth week. The expression of Cx43 and PCNA under intima was positive correlation in each test group.5. the expression changes of Cx43 under intima detected by Western blot was basicly accord with that by immunohistochemistry.Experiment â…¡. The Technical Exploration of Interventional Treatment for Occlusion of Aorto - iliac - femoral ArteryMaterials and Methods1. Clinical data34 patients with occlusion of aorto - iliac - femoral artery were treated, including 29 male and 5 female, aged from 28 years to 74 years ( mean 51. 2 years) , whose course was 3 days to 6 years ( mean at 11 months). There were 8 cases with the complete occlusion of inferior segment of abdomial aorta and bilateral iliac artery, including 3 cases with stenosis of renal artery. There were 23 cases with occlusion of single iliac artery, including 4 cases with occlusion of common femoral artery. There were 3 cases with occlusion of single superficial femoral artery only.2. Therapy methodsDuring operation, all the patients were respectively performed angiography in abdominal aorta and bilateral iliac and femoral arteries, puncturing femoral artery, brachial artery or popliteal artery to perform comprehensive interventional treatment, including local thrombolysis via catheter, recanalization of artery occlusion segment, preculaneous transluminal angioplasty ( PTA ) and stent placement.ResultsIn 34 patients with occlusion of aorto - iliac - femoral artery, the rate of re-canalization was 91.2% , which was 31 cases successful and 3 cases failure for the course of occlusion of iliac artery too longer and serious calcification. 8 ab-domial aortas, 36 iliac arteries, 4 common femoral arteries and 3 superficial femoral arteries were all recanalized via multiple puncturing pathways, thrombol-ysis by catheter and PTA. 46 naked stents and 3 coated stents were placed totally , including 6 abdomial aortas stents, 34 iliac artery stents and 2 common femoral artery stents, 4 superficial femoral artery stents and 3 renal artery stents. 1 patient with occlusion of external iliac artery that was restenosis after surgical bypass operation was placed 2 Wallstents across the iliac joint. In the 31 cases treated successfully, there were 9 cases with relief of symptom and sign and 21 cases with obvious improvement but 1 case with occlusion of abdominal aorta and bilateral iliac artery, resulting in right kidney completely atrophy and left kidney s function decline and sustaining life by renal dialysis, died of long - term chronical renal failure at 2^nd day after interventional treatment. There were 4 cases with complication: 1 case were observed with contrast medium overflow after iliac artery balloon dilation and 1 case were observed with false aneurysm after thrombolysis, both treated by coated stent placement; 2 cases were observed with acute occlusion lately after stent placement, recanalized after thrombolysis. All the patients were followed - up for 2-53 months ( mean 21. 5 months). A-mong them, 2 cases were treated again by intervenetional methods respectively at the 2^nd month and the 14^th month for reocclusion of inner stents and others' symptom appeared not to deteriorate.Experiment â…¢. The Clinical Application and Efficacy Observation of Stent Insertion for Chronic Occlusion of Iliac ArteryMaterials and Methods1. Clinical data63 patients were examined to be occlusion of iliac artery by angiography and there were 38 patients whose course was over 3 months (from onset of disease to diagnosis) , including 31 male and 7 female, aged from 41 years to 78 years( mean 58. 5 years). There were 46 occluded iliac arteries in 38 patients, including the occlusion of 18 common iliac arteries, 12 external iliac arteries and 16 both common iliac arteries and external iliac arteries. Main symptom of ischemia in artery of lower extremity was intermittent lameness, rest pain and gangrene.2. therapy methods and follow - up observation38 patients with occlusion of iliac artery (46 arteries in all) were performed by comprehensive interventional treatment, including local thrombolysis via catheter, recanalization of artery occlusion segment, precutaneous transluminal angioplasty (PTA) and stent placement. All patients were recorded contact manner in detail on admission, whom would be followed - up at the NO. 3,6, 12 month and each year after stent insertion. Whether the stents were unobstructed was evaluated by the patients'complication, body examination and brachi-um - ankle index examination. When stents were considered to be restenosis, which was varified by Doppler or angiography, second interventional recanalization was performed necessarily.ResultsAll occluded iliac arteries but 3 were recanalized and 54 stents were inserted in 43 occluded iliac arteries, the coverage lengh of which was 5 - 20cm with mean at 7. 4cm. 4 occluded common iliac arteries in initial segment were expanded by kissing balloon and performed stents instertion at both sides. 3-62 months fellow - up, mean at 29.5 months, showed the primary patency rate of stents was respectively 88%,84%,70% in 1 year, 2 years and 4 years after treatment. The cases with restenosis and reocclusion were treated by secondary interventional recanalization and the cumulative patency rate of stents was respectively 94% ,90% ,84%. There were 5 cases with complications, including 1 case with aorto arterial dissection ,2 cases with arterial embolism in distal end and 2 cases with iliac arteriorrhexis.