Influence of Simvastatin for In-stent Restenosis Rate and Blood Lipid Level and Inflammation Actor after Coronary Artery Stent Implantation

Objectives To investigate the effect of simvastatin on the probability of restenosis after stent implantation and serum level of lipids as well as high-sensitivity C-reactive protein (hs-CRP) in patients with coronary heart disease (CHD). Methods 118 patients with CHD after stenting therapy were divided into treatment group (n=62) and control group (n=56) randomly. All patients were treated with aspirin (100 mg/d) and clopidogrel (75 mg/d) while treatment group patients took simvastatin (40 mg qn) additionally. All patients underwent coronary angiography (CAG) to compare the difference of restenosis and the serum level of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), triglyceride (TG) as well as hs-CRP after the drug treatment for 6 months. Results The probability of restenosis was significantly lower in the treatment group than that of control group (P<0.01) and the results were similar between the patients with bare metal stent (P<0.01) and those with sirolimus-eluting stent (P<0.01). The serum levels of TC (P<0.01), LDL-c (P<0.01), TG (P<0.05) and hs-CRP (P<0.01) were obviously lower while the HDL-c (P<0.05) level was higher in the treatment group than those of control group. There was no death case. Conclusions Simvastatin could decrease the probability of restenosis significantly after coronary stent implantation with dose of 40 mg/d. It also has good performance on lipids control and lightening inflammatory reactions with its undoubtedly safety.

Experiment Study Of The Preventive Effects Of Valsartan ElutingStent On In - stent Restenosis

Objectives Background -Neointima hyperplasia and arterial remodeling are the main mechanisms of restenosis after percutaneous transluminal coronary angioplasty. The successful use of coronary stents neutralizes the acute elastic recoil and improves the remodeling mode with reducing restenosis rate by 10 % . But the in - stent neointima hyperplasia becomes more severe. This study aims to set up model of in - stent restenosis in vivo, and to e-valuate the preventive role of implantation of valsartan eluting stent for restenosis. Methods and Results Twenty - two male New Zealand white rabbits were divided into control group and valsartan group. In-travascular ultrasonic (IVUS) results showed the in-trastent neointimal areas of the control group were larger than those of the valsartan group (P < 0. 01) . The minimal lumen area of control group was smaller than that of the valsartan group ( P < 0. 01). Angiog-raphy results showed the normal lumen diameters were similar between two groups ( P> 0.05) . The lumen stenosis rates compared with the normal diameters of the valsartan group were significantly improved over that of the control group ( P < 0. 05) . It was comparable to the IVUS analysis. There were no cases of a-neurysm or thrombosis. Conclusions Valsartan e-luting stents produced a significant inhibition of neointimal hyperplasia and luminal encroachment in rabbits without obviously producing any serious side -effects. These results demonstrate the potential therapeutic benefit of valsartan eluting stents in the pre- vention and treatment of human coronary restenosis.

A systematic review of DVT and stent restenosis after stent implantation for iliac vein compression syndrome

Iliac vein compression syndrome(IVCS)is a common venous disease caused by joint compression of the right common iliac artery and the lumbosacral vertebrae.The compression of iliac vein not only causes venous hypertension in the lower extremities,but also induces venous valve dysfunction and superficial varicose veins in lower extremities.Moreover,the compression of iliac vein is an important potential factor for iliofemoral vein thrombosis.Currently,open surgery and stent implantation are the main treatment for IVCS.Due to the advantages of minimally invasive and postoperative patency,stent implantation for IVCS has gradually become the standard treatment.However,when the stent is implanted into the iliac vein to treat IVCS,the complications,such as restenosis,deep vein thrombosis(DVT)appear,which affect the patency of stent and hamper the patient recovery.Up to now,the mechanism how the stent implantation induces the restenosis and DVT is still unclear.In this review,we summarized the clinical symptoms,treatment methods of IVCS and the complications after stent implantation,and analyzed the mechanism of stent restenosis and DVT,and finally discuss the iliac vein stent design specifically for treating IVCS.

Comparison of long-term clinical outcomes after percutaneous coronary intervention between in-stent restenosis and de novo chronic total occlusion

Background The occurrence of in-stent restenosis(ISR)coronary chronic total occlusion(CTO)is presently increasing. However,there were few data related to the long-term clinical outcomes after percutaneous coronary intervention(PCI)between ISR CTO and de novo CTO. Methods A total of 435 CTO patients who had attempted PCI between Jan 2013 and November 2017 were screened for inclusion in this study. The Kaplan-Meier method was applied to estimate event-free survival and the log-rank test to compare long-term outcome. Cox regression analysis was used to identify associations between adverse events and risk factors. Results There were84 ISR CTO cases and 351 de novo CTO cases in this study. Successful revascularization was achieved similar between ISR CTO group and de novo CTO group(84.5% vs. 87.2%,P=0.592). The prevalence of MACE[17.9% vs. 9.1%;hazard ratio(HR):2.323;95% confidence interval(CI)1.233-4.37;P=0.004]and TLR(8.3% vs. 3.4%;HR:2.627;95% CI 1.05-6.53;P<0.016)were higher in the ISR CTO group,during the 2-year follow-up. Conclusions The procedural success rate of ISR CTO achieved was comparable to that of de novo CTO in the contemporary practice. But the long-term clinical outcome was significantly worse in term of major adverse cardiac events and target lesion revascularization.

Clinical and angiographic follow-up study of sirolimus-eluting stent for treatment of in-stent restenosis

With widespread performance of coronary artery stenting, the number of in-stent restenosis (ISR) has increased in recent years. How to treat ISR effectively has been a great challenge in the field of cardiology. Recently, some notable clinical trials have confirmed that sirolimus-eluting stents (SESs) (CYPHER^(TM), Cordis, J&J Inc, USA) reduce ISR rate dramatically. So far, there have been few reports on the efficacy of using SESs to treat ISR.^(1,2) So, we used SESs to treat 27 patients with ISR and followed up for at least six months.

Clinical Observation on Antiruisi Prescription (安替瑞丝方) in Preventing Restenosis after Coronary Artery Stenting

Antiruisi (AR)prescription (安替瑞丝方) is a compound in Chinese drug-therapy, which was used to treat 35 patients with coronary heart disease after stenting by the authors, and a satisfactory effect had been proved in preventing restenosis. It is reported as follows.

Impact of pathogen burden on in-stent restenosis in patients after coronary stent implantation

Background Although some certain infectious pathogens could be detected in the patients with coronary artery disease, the roles of these infectious factors in the development of coronary artery diseases remain largely unknown. Since the number of infectious pathogens has been argued to be relative to the coronary artery diseases, we therefore examined whether there is a link between the number of infections and the incidence of in- stent restenosis after stent implantation. Methods One hundred and eighty-one patients were enrolled in this study. Infectious pathogens including serum anti-Chlymydia p neumoniae, cytomegalovirus, Helico pylori, human herpes simplex virus-1, human herpes simplex virus-2 antibodies and hepatitis B virus antigen were measured in all patients before coronary stent implantation. Coronary angiography was performed before, immediately after and 6 months after stent implantation. Results Restenosis rate 6 months post stent implantation was similar in patients with low pathogen burden （ 〈3 pathagens, 33.3% ） to those with high pathogen burden （ ≥3 pathogens, 29. 1% ）. Conclusions Previous infections with Chlymydia pneumoniae, cytomegalovirus, Helico pylori, human herpes simplex virus-l, human herpes simplex virus-2 and hepatitis B virus do not contribute to the incidence of restenosis after stent implantation.

LOW-DOSE RADIOACTIVE ENDOVASCULAR STENTS PREVENT NEOINTIMAL HYPERPLASIA IN RABBITS RESTENOSIS MODEL

Objective To evaluate the effects of low-dose radioactive stents on the prevention of restenosis in rabbit model. Methods The stents were bombarded with suitable charged particles of adapted energy in the cyclotron to create a proper mixture of the radionuclides 59 Fe, 60 Co, 58 Co, 51 Cr, and 54 Mn. The radioactive stents were implanted in the iliac arteries of rabbits. The effects of radioactive stents on prevention of restenosis were assessed by angiography, histomorphometry and immunocytochemistry. Results All the iliac arteries that had been implanted with radioactive stents were patent on angiography and had no radiation complication during the 1～2 months of follow-up. There was a significant reduction in neointimal area (0.37±0.14mm 2 vs. 0.81±0.10mm 2, P<0.01), percent area stenosis (6.7±2.9% vs. 13.2±1.4%, P<0.01) and PCNA immunoreactive rate (2.00±1.58% vs. 10.88±6.98%, P<0.05) in the radioactive stent group compared with the control stent group. Conclusion Radioactive stents with an active of 0.91～1.65 μCi could inhibit SMC proliferation and neointimal hyperplasia in animal restenosis model. The low-dose radioactive stents are safe and feasible for prevention of restenosis.

Multivariate Analysis of Clinical Factors in Restenosis after Coronary Stenting

Ojbective To find the independent predictors for restenosis after coronary stenting. Methods Quantitative angiography was performed on 60 cases (67 successfully dilated lesions) after angio-plasty over 6-months follow-up, and both univariate and multivariate logistic regression analysis were done to i-dentify the correlations of restenosis with clinical factors. Results The total restenosis rate was 31. 3% (21 of 67 lesions), and according to univariate analysis the patients who underwent coronary stenting≥ 3. 5mm had a lower rate of restenosis ( P < 0. 01). Collateral circulation to the obstruction site, high maximal inflation pressure, smoking and the less minimal lumen diameter after PTCA made the rate of restenosis higherower ( P < 0. 05) . Multivariate logistic regression analysis showed that coronary stenting ≥3. 5mm had a low rate of restenosis, but high maximal inflation pressure and smoking made the restenosis rate higher. Conclusion Coronary stent size, maximal inflation pressure and. smoking were independent predictors for restenosis.

Local Delivery of C-myc Antisense Oligodeoxynucleotide by Gelatin Coated Platinium-Iridium Stent to Prevent Restenosis in a Normal Rabbit Carotid Artery

Objectives To investigate the feasibility and effect of local deliveryof c-myc antisense oligodeoxynucleotide (ASODN) by gelatin coated Platinium-Iridium stent to prevent restenosis in a normal rabbit carotid artery. Methods Gelatin coated Platinium-Iridium stent were implanted in the right carotid arteries of 32 rabbits under vision. Animals were randomized to the control group and the treated group receiving c-myc ASODN (n=16 respectively).7, 14, 30,90 days following the stenting procedure, morphometry for caculation of neointimal area and mean neointimal thickness were performed.The expression of c-myc protein was detected by immunohistochemical methods. Results 32 stents were successfully implanted into the right carotid arteries in 32 animals.Morphometric analysis showed that neointimal area and mean neointimal thickness siginificantly increased continuously up to 12 weeks after stent implantation,and at each time point , neointimal area and mean neointimal thickness were siginificantly smaller in the treated group than control group. (P<0.001,respectively).c-myc protein expression was weak positive or negative in treated group and positive in control group. Conclusions Gelatin coated Platinium-Iridium stent mediated local delivery of c- myc ASODN is feasibility , and it can inhibit neointimal hyperplasia to prevent restenosis in a normal rabbit carotid artery.

Influence of Strut Cross-section of Stents on Local Hemodynamics in Stented Arteries

Stenting is a very effective treatment for stenotic vascular diseases, but vascular geometries altered by stent implantation may lead to flow disturbances which play an important role in the initiation and progression of restenosis, especially in the near wall in stented arterial regions. So stent designs have become one of the indispensable factors needed to be considered for reducing the flow disturbances. In this paper, the structural designs of strut cross-section are considered as an aspect of stent designs to be studied in details. Six virtual stents with different strut cross-section are designed for deployments in the same ideal arterial model. Computational fluid dynamics（CFD） methods are performed to study how the shape and the aspect ratio（AR） of strut cross-section modified the local hemodynamics in the stented segments. The results indicate that stents with different strut cross-sections have different influence on the hemodynamics. Stents with streamlined cross-sectional struts for circular arc or elliptical arc can significantly enhance wall shear stress（WSS） in the stented segments, and reduce the flow disturbances around stent struts. The performances of stents with streamlined cross-sectional struts are better than that of stents with non-streamlined cross-sectional struts for rectangle. The results also show that stents with a larger AR cross-section are more conductive to improve the blood flow. The present study provides an understanding of the flow physics in the vicinity of stent struts and indicates that the shape and AR of strut cross-section ought to be considered as important factors to minimize flow disturbance in stent designs.

Sirolimus-eluting Stent for the Treatment of Small Coronary Artery Lesions:Comparison between Cypher and Firebird Stent

Objectives To evaluate the effectiveness of firebird stent for the treatment of coronary de novo lesion compared with cypher stent. Methods Ninety-one consecutive patients with 156 lesions who underwent coronary cypher (n = 68 lesions) and firebird (n = 88 lesions) implantation, quantitative coronary angiography (QCA) was performed at the time of stent implantation and subsequently at 8 months post-stenting. Small vessel disease was defined as ≤2.5 mm of reference vessel diameter measured by QCA. Major adverse cardiac events (MACE) including death, thrombosis, nonfatal myocardial infarction and target lesion revascularization (TLR) were compared between the two groups. Results Baseline clinical characteristics and angiographic parameters were similar between the two groups. Seven-month angiographic follow-up, the late loss was not different between the two groups (0.14 ± 0.38 mm vs 0.13 ± 0.17 mm, P > 0.05). Similarly, overall thrombosis rate were similar in both groups (1.5% vs 1.1%, P > 0.05). However, in-stent restenosis as well as in-segment restenosis rate were significantly higher in cypher group than that in firebird group (4.4% vs 0% and 19.1% vs 3.4%, P = 0.047 and P = 0.001 respectively). TLR was also higher in the cypher group (10.3% vs 2.3%, P = 0.033) compared with firebird group. Conclusions In this small sample size, non-randomized study, the data indicated that implantation of firebird stent for the treatment of small coronary lesion showed more favorable results in respective of restenosis compared with cypher stent implantation. A multi-center, large-sample size, randomized study, therefore, may be warranted.

Influence of Stent Implantation on the Expression of PCNA and Apoptosis in Injured Vascular Smooth Muscle Cells

Objectives To evaluate the impact of stent implantation on proliferation and apop-tosis in injured media vascular smooth muscle cells (VSMC) and to explore the mechanism of restenosis after stent implantation. Methods Fifty male New Zealand rabbits were randomized into two groups, including balloon group and stent group. Control group was set up. The samples were harvested on 3, 7, 14, 28, 56 days after operation and the following investigation was carried out: (1) Assessing the expression of proliferating cell nuclear antigen (PCNA) of media VSMC by the method of immunohistochemistry; (2) Analyzing apoptosis of media VSMC by DNA agarose gel electrophoresis and TUNEL technique. Results The expression of PCNA and apoptosis in stent and balloon groups were markedly increased compared with control groups. (1) Stent group induced significant increased expression of PCNA in the media VSMC compared with balloon group on 3 to 28 days. On day 7, the positive rates of PCNA were 24. 36±0. 55 % vs 18. 74±1. 09 % ( P < 0. 01 ); (2) From 3 to 28 days, stent group appeared obvious DNA ladder, while balloon group only had little trace ; (3) TUNEL method showed that stent group induced much more significant apoptosis than that of balloon group on 3 to 28 days. The highest rate of apoptosis appeared on day 7: 12. 42 ±1.13% vs 5. 54±0.53% (P<0. 01); (4) By calculating the ratio of the positive rate of PCNA to apoptosis, it showed that on 3 to 28 days, the ratio of balloon group was higher than that of stent group. There was obvious difference between two groups. Conclusions Stent group induces augmented proliferation and much more significant apoptosis of media VSMC than that of balloon group. It makes the ratio of proliferation to apotosis reduced and the severity of restenosis relieved after stent implantation.

Effect of Tongguan Capsules(通冠胶囊) on Restenosis after Coronary Stent Implantation:Study Protocol for A Randomized Controlled Trial

Background:Although percutaneous coronary intervention(PCI)had become widely employed therapeutic procedure for coronary artery disease,stent restenosis limited the benefits of this revascularization and the question how to prevent such events remained unresolved.While numerous empirical observations suggested Tongguan Capsules(通冠胶囊),a patented Chinese Medicine,could decrease frequency and duration of angina pectoris attacks,evidence supporting its efficacy on restenosis remained inadequate.Objective:This trial was designed to determine whether Tongguan Capsules would reduce restenosis rate in patients after successful stent implantation.Methods:Approximately 400 patients undergoing percutaneous coronary stent deployment were enrolled and randomized to control group or Tongguan Capsules(4.5 g/d)for 3 months.All patients received standard anti-platelet,anti-coagulation and lipid-decreasing treatments,concurrently.The primary clinical endpoint was the 12-month incidence of the major adverse cardiovascular events(defined as cardiac death,myocardial infarction,and recurrence of symptoms requiring additional revascularization).The angiographic end point was restenosis rate at 6 months.Conclusion:This study would provide important evidence for the use of Tongguan Capsules in patients after stent implantation in combination with routine therapies,which may significantly reduce incidence of the restenosis so as to potentially improve the clinical outcomes.(registration number:ChiCTR-TRC-ChiCTR-IIR-17011407)

The effect of magnetic stent on coronary restenosis after percutaneous transluminal coronary angioplasty in dogs

Objective To investigate the effects of magnetic stents on coronary restenosis after percutaneous transluminal coronary angioplasty (PTCA). Methods Twenty dogs were randomly divided into the control and experimental groups, each with 10 dogs. The control group was given common Palmaz-stents in the 6-8 segment of left anterior descending coronary artery or in the 11-14 segment of the left circumflexus. The experimental group was given magnetic stents in the same parts of the coronary arteries. The dogs were not given antiplatelet or anticoagulant drugs before or after the operation. Six months later, the 20 dogs were subjected to coronary angiographies, and then were sacrificed. Three centimeter long segments of the target vessels were cut for pathological examination. Results The degree of restenosis in 3 dogs of the control group was more than 50%, but none in the experimental group experienced restenosis. The average thickness of the tunica intima of the target artery was 2.98±0.56?mm in the control and 1.13±0.41?mm in the experimental group (P<0.05). Conclusion Magnetic stents could have a significant preventive effect on coronary restenosis.

The Prevention and Treatment of Restenosis in The Era of Drug-eluting Stent

Ever since the first percutaneous transluminal coronary angioplasty （PTCA） was completed successfully by Gruentzig in 1977, postoperational restenosis （RS） has been puzzling constantly the progress of percutaneous coronary intervention （PCI）, and it is known as the Achilles Heel of PCI. In a certain sense, the development history of PCI is also the history of continually overcoming RS.

Comparison of Results of Coronary Angioplasty in Patients with Unstable vs. Stable Angina

Objectives To compare the short and mid - term outcomes in cases of percutaneous transluminal coronary angioplasty (PTCA) in patients with unstable v stable angina. Methods Patients selected for PTCA/stenting were divided in to two groups, one with stable angina pectoris (SA group, n = 92) and one with unstable angina pectoris (UA group, n = 112). The outcomes of coronary an giographies (CAG), initial (30-d) success of the procedure, and follow - up status in the two groups were compared. Results Baseline characteristics were similar, although the patients with unstable symptoms more females ( P< 0. 05), and had a higher average CCS class (P< 0. 05) and a higher incidence of postinfarction angina ( P< 0. 01). The frequency of ' complex stenosis in patients with unstable angina was higher than that of patients with stable angina, 33% v 20% ( P< 0. 01). A total of 309 vessels ac cepted the procedure; including 210 stents were sue cessfully delivered to 156 patients. 143 and 67 stents were implanted in the UA and SA group, respectively ( P< 0. 01 ) . No major complication occurred in the two groups, except 12 patients experienced reoccur ring chest pain initially, 9 in UA group v 3 in SA group ( P< 0. 05). The averaged six - month follow -up status was compared too. Only 3 cases developed myocardial infarction, including 2 patients with unsta ble angina. 12 and 16 reoccurring chest pains were found in the two groups, respectively ( 13% in SA group vs 14% in UA group). There were no signifi cant differences between groups in rates of clinical restenosis, follow - up angina class, or overall clinical success. Conclusions Patients with unstable angina receiving PTCA/stenting have similar complication, restenosis, and initial and midterm success rate as compared to patients with stable symptoms with strict cases select and careful preparation.

Intravascular local gene transfer mediated by protein-coated metallic stent

Objective To assess the feasibility, efficiency and selectivity of adenovirus-mediated gene transfer to local arterial wall by protein-coated metallic stent.Methods A replication-defective recombinant adenovirus carrying the Lac Z reporter gene for nuclearspecific β-galactosidase (Ad-βgal) was used in this study. The coating for metallic stent was made by immersing it in a gelatin solution containing crosslinker. The coated stents were mounted on a 4.0 or 3.0 mm percutaneous transluminal coronary angioplasty (PTCA) balloon and submersed into a high-titer Ad-βgal viral stock (2 × 1010 pfu/ml) for 3 min, and then implanted into the carotid artedes in 4 mini-swines and into the left anterior descending branch of the coronary artery in 2 mini-swines via 8F large lumen guiding catheters. The animals were sacrificed 7 (n=4), 14 (n = 1) and 21 (n = 1 ) days after implantation, respectively. The β-galactosidase expression was assessed by X-gal staining.Results The results showed that the expression of transgene was detected in all animal. In 1 of carotid artery with an intact intima, the β-gal expression was limited to endothelial cells. In vessels with denuded endothelium, gene expression was found in the sub-intima, media and adventitia. The transfection efficiency of medial smooth muscle cells was 38.6%. In 2 animals sacrificed 7 days after transfection, a microscopic examination of X-gal-stained samples did not show evidence of transfection in remote organs and arterial segments adjacent to the treated arterial site.Conclusions Adenovirus-mediated arterial gene transfer to endothelial, smooth muscle cells and adventitia by protein-coated metallic stent is feasible. The transfection efficiency is higher. The coated stent may act as a good carrier of adenovirus-mediated gene transfer and have a potential to prevent restenosis following PTCA.

Astragaloside IV attenuates carotid intimal hyperplasia by suppressing the basic fibroblast growth factor expression in rats

Bacground Percutaneous coronary intervention（PCI） has become one of the most effective treatments in coronary heart disease（CHD）.However,the bottleneck problem of PCI is the in-stent restenosis（ISR）.The aim of this study was to explore the effects of astragaloside IV（AST IV） on suppression of intimal hyperplasia modulation of the expression of basic fibroblast growth factor（b-FGF） in a rat carotid artery balloon injury model.Methods Fifty healthy male Sprague-Dawley（SD）rats were randomly divided into five groups：a sham-operation group（sham）,a model group（model）,and three astragaloside IV-treated groups.Three days before the surgery,1% carboxy methyl cellulose（CMC） or AST IV（20,40 or 60 mg·kg^（- 1）·d^（- 1）） was intragastrically administered into sham or 3 astragaloside-treated groups once a day for 17 days.Hematoxylin-elsin staining was carried out to determine the pathomorphological changes and the neointimal and media area ratio.Immunohistochemistry staining was performed to measure the expressions of proliferating cell nuclear antigen（PCNA）and basic fibrolast growth factor（b-FGF）.PCNA and b-FGF were analyzed with Iamage-Pro Plus.Results（1） The carotid artery intimal hyperplasia in the rats of model was similar to lumen stenosis.Compared with the sham operation group,the area of the new intima and the ratio of the intima to media（I/M） were increased and the lumen area was decreased（P 〈 0.01） in the model group.Astragaloside IV increased the lumen intimal dimension and decreased the area of new intima and the ratio of intima to media in a dose-dependent manner.（2） Compared with the sham-operation group,the expressions of PCNA and b-FGF in carotid artery of model group were significantly increased（P 〈 0.01）.AST IV decreased expressions of PCNA and b-FGF in the carotid artery of rats in a dosedependent manner.Conclusion Astragaloside IV significantly inhibits neointimal hyperplasia of rat carotid artery through down-regulating the expressions of PCNA and b-FGF.