Objective To compare the effects of different doses of adenosine(AD)on the left coronary blood flow(CBF)and left coronary flow reserve(CFR)in mini-swine.Methods By using Doppler flow wire and intracoronary ultrasound imaging catheter at the middle segment of LAD,coronary average peak flow velocity(APV)and lumen area were measured in 10 healthy mini-swines.CBF was calculated from the equation of 0.6 APV times 0.5 lumen area.Intracoronary bolus injection of different dose AD(12μg,18μg,24 μg and 36μg,separately)was used to induce maximal coronary hyperemic reaction.CFR was defined as the ratio of hyperemic CBF to resting CBF.Results Intracoronary bolus injection of 18μg AD level induced a maximal coronary vasodilation.Significant difference in the hyperemic CBF existed between 12 μg AD dose and 24μg or 36μg AD dose(P＜0.05).No significant difference in heart rate,blood pressure,rCBF and CFR was found among three different AD dose groups(18μg,24μg,and 36μg).Conclusion CBF and CFR in mini-swine can be effectively assessed by bolus injection of AD with the dose of(18～24)μg.

Objective To make a preliminary evaluation of the degradation of AZ31 bioabsorbable magnesium alloy stent implanted in the abdominal aorta of experimental rabbits.Methods Twelve AZ31 biodegradable magnesium alloy stents were separately deployed in the infrarenal abdominal aortas of twelve New Zealand white rabbits.Every three experimental rabbits were sacrificed each time at one,two,three and four months after the procedure of stenting.The stenting segment of the aortas were harvested,radiographod and sent for pathologic examination to observe the degradable performance of the stent.Results All animals survived form the operation in the scheduled follow-up period.Radiographically and pathologically,the stents were fully expanded with perfect shape one month after the procedure,and part of the stent struts began to be degraded and fractured in two months,resulting in the loss of its supporting function.Three months after the implantation most stents were corroded.and in four months all the stents become completely destroyed.The estimating time for producing complete degradation of AZ31 magnesium alloy stents in rabbit's aorta was 104.5 days.Conclusion AZ31 bioabsorbable magnesium alloy stents implanted in rabbit abdominal aorta will lose their radial force in two months.How to prolong the functioning time of the implanted stents is the next research target.

Objective To investigate the relationship between the liver pain and the short-term curative effect in patients with primary hepatocellular carcinoma(HCC)after transcatheter arterial chemoembolization(TACE).Methods According to the degree of liver pain,118 HCC patients after the initial TACE treatment were divided into two groups:group A(with no complaint of serious liver pain)and group B (complaining of severe liver pain).Short-term curative effects at the fourth and sixth week after initial TACE were compared between the two groups,and the factors related to the liver pain after TACE were analyzed.Results Four to six weeks after the initial TACE,CT scan was performed in all patients.Based on the RECIST criteria the short-term curative effects were evaluated.The CR,PR,SD,PD of group A and B were 0%.1.45%.88.41%,10.14%and 0%,14.29%.81.63%,4.08%,respectively.The difference in OR(CR +PR)between two groups was statistically significant(P=0.0087).The postoperative liver pain was probably related to the preoperative tumor blood supply pattern,the tumor capsule.the cirrhosis and the type of iodized oil deposit.The type of iodized oil deposit showed a negative correlation with the grade of liver pain (r=-0.539,P＜0.001).Conclusion The liver pain occurred after TACE is a useful suggestive sign,which indicates that a good curative result will be obtained.It is of clinical significance to make a full understanding of the relationship between the liver pain and the therapeutic effect.

The coronary covered stents have been more and more used to treat intracranial arterial diseases for recent years,and the hot point in study has gradually changed from clinical application of coronary covered stents to the fundamental and clinical trial of specially-designed intracranial covered stentsThe covered stents are mainly employed for the treatment of intracranial arterial disorders,including giant,wide-necked or minute cerebral aneurysms,intracranial pseudoaneurysms caused by a variety of reasons,fusiform or dissecting aneurysms of vertebral-basic artery,and internal carotid cavernous fistula,etc.It is very difficult for current surgical or endovascular treatment,both materially and technically,to deal with the above mentioned intracranial disorders.The covered stent can restore the anatomic shape of artery by direct sealing the aneurysmal neck and the fistula.The complications of covered stent treatment include defect of cranial nerves,occlusion of parent artery or branches.This article aims to review the related medical literature published both at home and abroad,to make a retrospective analysis of the therapeutic results,and to put forward some issues of common interest.

Objective To discuss the nursing measures for patients of hepatocellular carcinoma treated with transcatheter hepatic arterial chemoembolization(TACE)and hish intensive focus ultrasound (HIFU).Methods During the period of Aug.2008-Aug.2009,TACE together with HIFU were performed in 40 patients with hepatocellular carcinoma.The perioperative nursing measures were summarized.Results During hospitalization no severe complications,such as dangerous infection,intestinal bleeding,etc.occurred in all patients.Conclusion Correct and proper periopemtive nursing care is of significant importance for the prevention of complications and for the therapeutic effectiveness.

Objective To assess the effectiveness of uterine arterial embolization for the treatment of hysteromyomas and to discuss the factors related to the clinical results.Methods Super-selective uterine arterial embolization was performed in forty-five patients with hysteromyomas.Of 45 patients,multiple hysteromyomas were seen in 36 and solitary lesion in 9.The lesion was located at the myometrium in 41 cases,among them coexisted endometrioma was found in 5 cases and coexisted submucosal myoma in 2.The lesion was located submucous layer in the remaining 4 cases.The diagnosis was confirmed by imaging study and gynecological examination.After the operation,ultrasonography and laboratory tests were carried out in all patients to observe the tumor size.hormone levels and hemoglobin concentration.Results A total of 91 uterine arteries were found in 45 patients.including double left uterine arteries in one case.Successful catheterization was obtained in 87 arteries(95.6%).All forty-five patients were followed up for 6-36 months.Six months after the procedure the mean reduction of the tumor size was 69.3%.and the lesion completely disappeared in two cases.In the anemic patients the hemoglobin concentration returned to normal level.The main side-effects included low fever and pain at lower abdomen.Conclusion Uterine arterial embolization is a safe and effective treatment for hysteromyomas.

Objective To investigate the effects of intratumoral implantation of ~(32)P-CP-PLLA seeds on the normal canine liver tissue and to exolore the metabolism of ~(32)P-CP-PLLA seeds implanted in the liver of experimental dogs.Methods Twelve beagles were enrolled in this study.The dogs were randomly and equally divided into four groups:group A(185 MBq),group B(370 MBq),group C(740 MBq)and group D(0 MBq).By using laparotomy procedure ~(32)P-CP-PLLA seeds were implanted into dog's liver.CT scan was performed before operation as well as before the dog was sacrificed.All dogs were sacrificed three months after the implantation.Before the procedure and 1,2,4,8 and 12 weeks after the procedure the blood tests and serum biochemical tests were conducted.One dog from group B and group C was selected respectively and was fed in a metabolic cage.Within one month after the procedure the cpm in feces and in urine was determined every 24 hours.One dog was picked out from each of the three groups and was punctured to get its liver tissue for pathologic exam each time at 1,2,4,8 and 12 weeks after the implantation,and SPECT imaging was also performed at the same time.Pathologic study,both macroscopic and microscopic(including optical and electronic microscopy)was made to observe the liver damage after the dog was sacrificed.The statistical analysis was processed by using SPSS 13.0 software and the measuring data were expressed with mean±standard deviation((x)±s).Results Two months after the procedure,serological examination found that the serum alkaline phosphatase(BKP)in both group Band group C was significantly higher than that in other groups,the difference was statistically significant (P ＜0.05),and the BKP levels returned to normal in three months.The postoperative 30-day inspection of the urine showed that the radioactive particles slowly released into the body and eliminated from the body with the urine and feces,mainly through the renal excretion.The 30-day cumulative percentage of eliminated radioactive dose in the urine and in the feces was 6.34% and 11.64% respectively.No sign of particle displacement was found on SPECT imaging.On autopsy three months after the implantation,the size of the radioactive seeds became smaller and fragile.With the radioactive dose used increasing,the area of liver damage at the site of seed implantation became bigger,which was demonstrated on CT scan,macroscopic exam and pathologic study.The local damaged focus of the liver caused by ~(32)P-CP-PLLA seeds was manifested as a spherical lesion which was encysted by a layer of fibrous tissue with an edematous zone peripherally.Conclusion The implantation of ~(32)P-CP-PLLA seeds in dog's liver causes only localized hepatic damage with no general adverse effects.The implanted seeds can slowly release the radioactive dose and will not immigrate to other organs in the body.Besides,the seeds possess excellent stability,targeted orientation and safety.

Objective To establish a carotid siphon aneurysm model in dogs in order to test the mechanical features of a newly-designed Willis covered stent-graft and to investigate the histological reaction of the stent-implanted vessel during a follow-up period of 12 months.Methods Twenty-four saccular sidewall aneurysms were surgically created in twelve dogs(group A)and 12 carotid siphon aneurysms in another twelve dogs(group B).A Willis stent-graft was implanted in each aneurysm.Angiography was performed immediately after the procedure and 1,3,6 and 12 months after the implantation to investigate the aneurysm isolation,endoleak,stent angulation,and the patency or restenosis of the parent artery.Light and scanning electronic microscopy were used to identify aneurysmai sac thrombi,intima hyperplasia and endothelial progress of the stent-loaded arterial segment.Results In group B,postoperative immediate angiography demonstrated that two aneurysms had mild endoleak and three stents became angulated.Follow-up exam 12 months after the procedure revealed that all previous endoleaks disappeared,one parent artery became occluded and three parent arteries developed mild stenosis(＜50%).In group A.occlusion of parent artery was seen in one and mild stenosis(＜50%)in 2 cases.Electronic microscopy revealed new intima formation in all stents,and all aneurysmal sacs were filled with thrombi.In group B.the endothelialization process was not completed until 12 months after the stent implantation,and a marked correlation existed between endothelial cell arrangement and the hemodynamic orientation.Conclusion It is feasible to treat carotid-siphon aneurysm in dog with a Willis stent-graft.The complete endothelialization of the covered stent in tortuous vessel takes longer time than that in rather straight vessel.

Objective Acute massive pulmonary embolism(PE)is a clinical emergency requiring rapid and supportive measures.With the development of interventional technology and devices,percutaneous mechanical thrombectomy(PMT)is considered to be an alternative for the treatment of PE,though there is still relative lack of clinical experience.The purpose of this study is to evaluate the clinical efficacy and safety of PMT in the management of acute massive PE.Methods The clinical data of massive PE patients treated with interventional methods were collected and analyzed in a retrospective way.From Jan.2003 to Jan.2008,6 patients(5 males and one female,with a mean age of 62 years)with acute massive PE,which was initially diagnosed by computed tomography and finally confirmed by pulmonary angiography,were treated with percutaneous catheter fragmentation and/or Straub Rotarex thrombectomy device.Results The improvement of clinical status and restoration of blood flow in the main branches of pulmonary artery were obtained in all patients.Oxygen saturation(SaO2)increased from preoperative(79.5±5.3)%to postoporative (92.8±3.4)%,with P＜0.01.Partial arterial oxygen pressure(PaO2)increased from preoperative(58.0±9.8)mmHg to postoperative(88.7±4.1)mmHg(P＜0.01).After PMT treatment,the mean pulmonary artery pressure(PAP)decreased from preoperative(40.8±7.8)mmHg to postoperative(29.8±8.0)mmHg (P＜0.01).Miller index decreased from preoperative 0.54±0.03 to postoperative 0.18±0.07(P＜0.01).During a clinical follow-up period ranged from 1 to 5 years,four patients showed no recurrence of PE,the other two patients lost touch with the authors.Conclusion The preliminary experience in onr series suggests that PMT is an easy,effective and safe therapy in the clinical management of acute massive PE,especially when thrombolysis is contraindicated.

Objective To evaluate the feasibility and effectiveness of endoluminal grafting for the treatment of abdominal aortic aneurysms in high-risk patients with serious co-morbidities.Methods Endoluminal stent grafting was performed in fifty-one patients(45 males and 6 females,with a mean age of 71.6±7.5 years)with abdominal aortic aneurysms.Of all the patients,21(37.7%)were high-risk surgical candidates because of associated co-morbidities.These patients were classified in grade Ⅱ and Ⅲ according to the criteria assigned by the"Society for Vascular Surgery"and"International Society for Cardiovascular Surgery".Based on the preoperative CT and DSA findings,the appropriate stent was selected for every patient.Post-operative clinical observation and CT scan were regularly carried out,the occurrence of complications and the morphological changes of the aneurysms were observed.The results were evaluated and analyzed.Results Primary technical success was achieved in all patients(100%).No death occurred during the procedure or in 30 days after the procedure.An average follow-up period of(29.1±20.5)months was made.Minor endoleak was noted on CT scans in 10 patients,and the endoleak disappeared in 5 patients during the follow-up period.One patient died from unknown cause.The total mortality rate was 2.0%(1/51).The major complications rate was 9.8%(5/51),including stent thrombosis(n=2),thrombosis at femoral artery(n=1),lymphatic fistula at femoral incision(n=1) and stent dislocation(n=1).Conclusion Endoluminal stent grafting is a safe and feasible technique for the treatment of abdominal aortic aneurysms with excellent medium-term results.This technique is especially suitable for the patients with high surgical risk.