Long-term results of implantation of bioengineered and drug-eluting stents in patients with coronary heart disease: comparative characteristics of predictors of poor prognosis

The purpose of the investigation was to study the morphological and clinical characteristics affecting the long-term prognosis after implantation of bioengineered and drug-eluting stents in patients with coronary heart disease (CHD). The investigation covered 2362 patients with CHD. Genous bioengineered stents were implanted in 316 patients; Cypher rapamycin-eluting stents were in 2046 patients. The independent poor factor for complications was discontinuation of antiaggregatory therapy due to surgical interventions of different types in the drug-eluting stent group and stenting of extensive stenoses in the bioengineered stent group.     

Efficiency of endovascular re-interventions for evolving restenosis of different types of stents

The paper compares the results of different treatment options (balloon angioplasty and restenting) for in-stent restenosis in case of evolving restenosis of drug- and nondrug eluting stents. The investigation enrolled 496 coronary heart disease patients with clinical presentation of angina pectoris and/or signs of myocardial ischemia, as well as hemodynamic restenosis of a previously implanted stent. Of them, 216 and 280 patients had restenosis of previously implanted drug- and nondrug-eluting stents, respectively. In the patients with non-drug-eluting stent restenosis, recurrent angina pectoris and the frequency of repeated restenosis were significantly more frequently observed after balloon dilatation than after drug-eluting stent implantation (28.4 and 10.2%; p < 0.05; 19.9 and 8.7%; p < 0.05). In those with drug-eluting stent restenosis, recurrent angina pectoris and the frequency of repeated restenosis did not differ significantly between balloon dilatation of restenosis and implantation of a second drug-eluting stent.     

Long-term clinical efficiency of endovascular treatment using Cypher rapamycin-eluting stents in patients with coronary heart disease

The study was undertaken to analyze the long-term results in patients with coronary heart disease (CHD) one year or more after Cypher stent implantation. It covered 1221 patients. One-, two-, and three- vessel lesions were observed in 693 (56.8%), 344 (28.2%), and 184 (15%) patients, respectively. A total of 1967 Cypher stents were implanted. The results of treatment were analyzed 1 and 2 years after intervention. The efficiency of a procedure was evaluated by the following parameters: the presence or absence of anginal symptoms, the presence and absence of complications (fatal outcome, myocardial infarction). The following morphological parameters: the rate of restenosis and that of late stent thrombosis were also assessed. The results of one- and two-year follow-ups were used to make a multivariate analysis of the clinical and morphological predictors of coronary complications (fatal outcome, myocardial infarction, recurrent angina pectoris) in the late period, as well as the predictors of restenosis and late stent thrombosis. Restenosis following 1 year of Cypher stent implantation is 3.1%. The factors that significantly increase the risk of this complication within the first year are diabetes mellitus and revascularization in the patients operated on. The one-year rate of Cypher stent thromboses is 1.6%. Patients' discontinuation of antiaggregant therapy is the sole factor that significantly increases the rate of their late thromboses in this period. Within the second year of a follow-up, the rate of late Cypher stent thromboses is 1.8%. The risk of this complication is significantly increased by factors, such as a lengthy (more than 3 mm) stented portion, renal failure, and less than 40% left ventricular ejection fraction.     

Would SYNTAX have been a positive trial if XIENCE V had been used instead of TAXUS?: A meta-analysis of a first-generation vs. a second-generation drug-eluting stent system

Treatment options for coronary revascularisation include percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). In the ‘synergy between PCI with TAXUS and cardiac surgery (SYNTAX)’ trial, PCI and CABG using state-of-the-art techniques (using paclitaxel-eluting stents and arterial grafts, respectively) were compared in the treatment of complex coronary artery disease. In Syntax, PCI was inferior to CABG at one year, entirely due to an increased repeat intervention rate. We hypothesised that the use of a superior drug-eluting stent system could reduce the need for repeat intervention. (Neth Heart J 2010;18:451-3.)     

冠状动脉内重叠支架置入术的临床研究进展

重叠支架置入术是临床上用来治疗冠状动脉弥漫性长病变的常用方法,以往曾采取重叠裸金属支架置入术,但其临床预后不佳,目前较为常用的重叠药物洗脱支架置入术被认为相对安全、有效,但仍存在许多潜在问题。本文介绍了适合使用重叠支架置入术进行治疗的冠状动脉病变的特点,回顾了重叠裸金属支架的临床应用情况,阐述了近年来药物洗脱支架的发展以及重叠药物洗脱支架置入术的优势,比较了四种负载不同药物的药物洗脱支架同种重叠置入后的临床疗效,观察了异种药物洗脱支架混合重叠置入后的临床特点和支架重叠段对临床预后的影响,分析了重叠支架置入术与几种其它治疗冠状动脉弥漫性长病变方法的应用区别,并对新一代药物支架的重叠应用进行了展望。     

Long-term results of chronic occlusion recanalization in patients with coronary heart disease

The study was undertaken to assess the long-term results of recanalization of chronically occluded coronary arteries, by applying drug-eluting stents to patients with coronary heart disease. The study enrolled 585 patients with one-vessel occlusive lesion of one of three great coronary arteries (TIMI 0; occlusion duration, > or = 3 months): 321 patients who underwent successful recanalization of chronic occlusion and further implantation of drug-eluting stents and 264 patients who received drug therapy (a control group). The short- and long-term results of recanalization were investigated. The follow-up averaged 1095 +/- 36 days; reexaminations were made after 1, 2, and 3 years. The direct success rate of recanalization of chronically occluded coronary arteries was 84.9% (321/378). The results of a 3-year follow-up showed the efficiency and expediency of endovascular recanalization of chronic occlusions: the invasively treated patients had the symptoms of angina pectoris and heart failure significantly less frequently, showed higher exercise tolerance and a less need for antianginal therapy, and had a better long-term prognosis.     

国产雷帕霉素药物洗脱支架在冠心病介入治疗中疗效评价

目的:观察国产雷帕霉素药物洗脱支架在冠心病介入治疗中有效性及安全性。方法:2010年1月至2010年12月我院心血管内科收治并行国产雷帕霉素药物洗脱支架(Firebird支架)置入术患者124例,收治并行进口雷帕霉素药物洗脱支架(Cypher^TM支架)置入术患者167例,于不同支架置入患者中各随机选68例,命名为国产组与进口组。术后1年、5年分别随访两组,观察两组患者支架置入后在不同时间段不良心血管事件发生情况及冠脉造影复查结果。结果:两组患者不良事件比较,国产组术后1年随访结果与术后5年随访结果比较,差异无统计学意义(P0.05);进口组术后1年随访结果与术后5年随访结果比较,差异无统计学意义(P0.05);国产组术后5年随访结果与进口组术后5年随访结果比较,差异无统计学意义(P0.05)。两组患者冠脉造影复查结果比较,差异无统计学意义(P0.05)。结论:国产雷帕霉素药物洗脱支架在冠脉介入治疗中具有安全性和有效性,与进口雷帕霉素药物洗脱支架比较无明显差异,值得临床推广应用。     

Results of point stenting of extended coronary stenoses in patients with ischemic heart disease

The paper analyzes the immediate and long-term results of point stenting in patients with extended (more than 30 mm) coronary stenoses and compares them with those obtained by routine stenting. The study included 177 patients with varying extent stenoses who underwent traditional implantation of intracoronary stents. Thirty-seven patients undergone the so-called point stenting formed a separate group. There was no significant difference in clinical and angiographic success rates between the patients of all three groups. Significant difference was also absent in subacute stent thrombosis between the patients of Groups 2 and 3 and those of the point stenting group. Thus, acute or subacute stent thrombosis was noted in 4 (2.3%) patients from the routine stenting groups, all the patients being from Groups 2 and 3, and in 2 (5.4%) from the point stenting group. No significant difference was found in the incidence of recurrent angina pectoris (restenosis) between Groups 1 and 2 and between Groups 2 and 3. At the same time, recurrent angina (restenosis) significantly more frequently developed in the patients of Group 3 than those of Group 1. As compared with Groups 2 and 3 patients, there was no significant difference in the incidence of recurrent angina (restenosis).     

Results of point stenting of extended coronary stenosis in patients with ischemic heart disease

The paper analyzes the immediate and long-term results of point stenting in patients with extended (more than 30 mm) coronary stenoses and compares them with those obtained by routine stenting. The study included 177 patients with varying extent stenoses who underwent traditional implantation of intracoronary stents. Thirty-seven patients undergone the so-called point stenting formed a separate group. There was no significant difference in clinical and angiographic success rates between the patients of all three groups. Significant difference was also absent in subacute stent thrombosis between the patients of Groups 2 and 3 and those of the point stenting group. Thus, acute or subacute stent thrombosis was noted in 4 (2.3%) patients from the routine stenting groups, all the patients being from Groups 2 and 3, and in 2 (5.4%) from the point stenting group. No significant difference was found in the incidence of recurrent angina pectoris (restenosis) between Groups 1 and 2 and between Groups 2 and 3. At the same time, recurrent angina (restenosis) significantly more frequently developed in the patients of Group 3 than those of Group 1. As compared with Groups 2 and 3 patients, there was no significant difference in the incidence of recurrent angina (restenosis).     

Comparison of ReoPro((R)) (abciximab) versus intracoronary thrombolysis for early coronary stent thrombosis

AIMS: This study evaluated the treatment of early coronary stent thrombosis with intracoronary urokinase or the platelet glycoprotein IIb/IIIa receptor inhibitor ReoPro (abciximab). METHODS AND RESULTS: Seventy-four patients (126 stents) were treated immediately after identification of early (0-30 days) coronary stent thrombosis. Twenty-nine patients were treated with intracoronary urokinase (UK) (UK alone in 19; UK and additional balloon angioplasty in 10) and another 45 patients were given ReoPro((R)) (abciximab) (0.25 mg/kg as a bolus alone in 26, abciximab with additional balloon angioplasty in 19) within 30 days of stent implantation. TIMI grade 3 flow was obtained in 23 patients (79%) in the UK group and in 38 (84%) in the abciximab group (nonsignificant). Three patients (10%) in the UK group and one (2%) in the abciximab group underwent repeat percutaneous transluminal coronary angioplasty (PTCA) (nonsignificant). Five patients (17%) in the UK group and three (7%) in the abciximab group were referred for urgent coronary artery bypass graft surgery (CABG) because of residual thrombus and refractory ischemia (nonsignificant). Repeat revascularization was necessary in eight patients (28%) in the UK group versus four (9%) in the abciximab group (p < 0.05). Five patients (17%) in the UK group and eight (18%) in the abciximab group developed myocardial infarction (nonsignificant). Five patients (17%) in the UK group (cardiogenic shock (three), cerebral hemorrhage (one) and pneumonia (one)) and three (6.6%) in the abciximab group (cardiogenic shock (two), heart failure (one)) died within 30 days (nonsignificant). Overall, noncardiac complications (bleeding including surgical repair of groin) were observed in 11 patients (38%) in the UK group and three (7%) in the abciximab group (p < 0.001). CONCLUSION: Compared to urokinase, abciximab reduced the need for repeat revascularization procedures and the risk of noncardiac events, including bleeding complications in patients with early coronary stent thrombosis.     

Intravascular-ultrasound-guided percutaneous transluminal coronary angioplasty/provisional stent implantation strategy: impact on long-term clinical follow-up

Two hundred and eighty-four consecutive patients with 438 native coronary artery stenoses were enrolled prospectively in a study of intravascular ultrasound (IVUS)-guided percutaneous transluminal coronary angioplasty (PTCA) with provisional stenting: (1) aggressive lesion-site media-to-media balloon-sizing; (2) IVUS-assessment of residual lumen dimensions to identify optimal PTCA results (minimum lumen area = 65% of the average of the proximal and distal reference lumen areas or = 6.0 mm(2) and no major dissection); and (3) liberal stent crossover. Overall, 206 stenoses in 134 patients (47%) were treated with PTCA alone. Reasons for crossover were flow-limiting or lumen-compromising dissections in 28% of patients and suboptimal IVUS minimum lumen area in 72% of patients. At one year, 8% of stenoses in the PTCA group and 16% in the stent crossover group required revascularization. In approximately half of the patients treated using an IVUS-guided aggressive PTCA strategy, stent implantation could be avoided without sacrificing an increase in acute complications or worse clinical outcome.     

Biodegradable stents as a platform to drug loading

Despite technical and mechanical improvement in coronary stents the incidence of restenosis caused by in-stent neointimal hyperplasia remains high. Oral administration of numerous pharmacological agents has failed to reduce restenosis after coronary stenting in humans, possibly owing to insufficient local drug concentration. Therefore, drug-eluting stents were developed as a vehicle for local drug administration. The authors developed a new drug-eluting polymer stent that is made of poly-l-lactic acid polymer mixed with tranilast, an anti-allergic drug that inhibits the migration and proliferation of vascular smooth muscle cells induced by platelet-derived growth factor and transforming growth factor->1. Polymer stents might be superior to polymer-coated metallic stents as local drug delivery stents in terms of biodegradation and the amount of loaded drug. Drug-mixed polymer stents can be loaded with a larger amount of drug than can drug-coated metallic stents because the polymer stent struts can contain the drug. Clinical application is required to assess the safety and efficacy of drug-eluting polymer stents against stent restenosis.     

Nanoparticulate carriers for the treatment of coronary restenosis

The current treatment for coronary restenosis following balloon angioplasty involves the use of a mechanical or a drug-eluting stent. Despite the high usage of commercially-available drug-eluting stents in the cardiac field, there are a number of limitations. This review will present the background ofrestenosis, go briefly into the molecular and cellular mechanisms of restenosis, the use of mechanical stents in coronary restenosis, and will provide an overview of the drugs and genes tested to treat restenosis. The primary focus of this article is to present a comprehensive overview on the use of nanoparticulate delivery systems in the treatment of restenosis both in-vitro and in-vivo. Nanocarriers have been tested in a variety of animal models and in human clinical trials with favorable results. Polymer-based nanoparticles, liposomes, and micelles will be discussed, in addition to the findings presented in the field of cardiovascular drug targeting. Nanocarrier-based delivery presents a viable alternative to the current stent based therapies.     

Sensor to detect endothelialization on an active coronary stent

Background  

A serious complication with drug-eluting coronary stents is late thrombosis, caused by exposed stent struts not covered by endothelial cells in the healing process. Real-time detection of this healing process could guide physicians for more individualized anti-platelet therapy. Here we present work towards developing a sensor to detect this healing process. Sensors on several stent struts could give information about the heterogeneity of healing across the stent.     

Results of coronary stenting in relation to the length of an implanted stent

The paper considers the impact of the length of an implanted stent on the early and late outcomes of intracoronary stenting. The study included 177 patients on a retrospective basis. They all underwent intracoronary stenting of 215 stenoses. All the patients were divided into three groups in relation to the length of an implanted segment (under 20 mm, 20-30 mm, and under 30 mm). In 16 (9.04%) of the 177 patients, for complete stenosis correction, several, but not one, stents were inserted, i.e. multiple stenting of a coronary stenting was performed. The stents were implanted by the conventional procedure. There was no significant difference in clinical and angiographic success rates between the patients of all three groups. There were no complications, such as transmural myocardial infarction and deaths in any groups. Acute stent thrombosis was noted only in 1 (1.8%). There was no significant difference in the incidence of subacute stent thrombosis between Groups 2 and 3 patients. No case of subacute thrombosis of implanted stents was noted in Group 1 patients. Thus, acute and subacute stent thromboses were observed in 4 (2.3%) patients, they being all from Groups 2 and 3. There was no significant difference in the development of restenosis between Groups 1 and 2 and Groups 2 and 3. At the same time, restenosis significantly more frequently developed in patients from Group 3 than in those from Group 1. Thus, the findings indicate that the length of a stented segment is an important factor that influence both early and late outcomes of intracoronary stenting.     

Gene delivery from a DNA controlled-release stent in porcine coronary arteries

Expandable intra-arterial stents are widely used for treating coronary disease. We hypothesized that local gene delivery could be achieved with the controlled release of DNA from a polymer coating on an expandable stent. Our paper reports the first successful transfection in vivo using a DNA controlled-release stent. Green fluorescent protein (GFP) plasmid DNA within emulsion-coated stents was efficiently expressed in cell cultures (7.9% +/- 0.7% vs. 0.6% +/- 0.2% control, p < 0.001) of rat aortic smooth muscle cells. In a series of pig stent-angioplasty studies, GFP expression was observed in all coronary arteries (normal, nondiseased) in the DNA-treated group, but not in control arteries. GFP plasmid DNA in the arterial wall was confirmed by PCR, and GFP presence in the pig coronaries was confirmed by immunohistochemistry. Thus, DNA-eluting stents are capable of arterial transfection, and could be useful as delivery systems for candidate vectors for gene therapy of cardiovascular diseases.     

Use of Rtrade mark stent in the percutaneous coronary intervention of coronary bifurcation lesions

BACKGROUND: Percutaneous Coronary Intervention (PCI) of coronary bifurcation lesion is technically quite demanding. It has been associated with a lower procedural success, higher rates of complication and restenosis. Side-branch occlusion and plaque shifting or 'snow plow' effect are not uncommon. Stenting of the main vessel may cause 'stent jail' of the side-branch. Modern stent design may allow passage of a balloon or stent into the side-branch through the struts of the stent placed in the main vessel. A newly developed 316 stainless steel tubular stent, the Rtrade mark stent is uniquely designed to provide flexibility, radial strength on deployment and conformability. Its large cell size facilitates PCI of bifurcation lesion. AIM: To assess the feasibility of R(trade mark) stent in the treatment of symptomatic patients with bifurcation coronary lesions. The main objective was to assess the ease of deployment, side-branch access and overall success of the R(trade mark) stent in this group of patients without any major adverse events. METHODS: Between December 1998 and September 2000 the R(trade mark) stent was used as a main stent in 28 consecutive patients with coronary bifurcation lesions, 46% of which had unstable angina. The mean age was 59 +/- 10 and 89% were male. Adjunctive medical therapy included clopidrogel, aspirin and intraprocedure heparin. Abciximab (ReoPro) was given to 9 patients. RESULTS: Successful stent deployment was achieved in all patients. Thirty-four R Stents and 16 other stents were used. Two patients had post-procedure rise in cardiac enzymes. There were no major adverse events at 30 days. LAD/D1 with LAD/diagonal was the target lesion in the majority of patients. Stenting of the side-branch was done in 18 and balloon dilatation in 9 patients. At 3-23 months (mean 11.8) follow-up, repeat angiography was done in 18 patients with restenosis in 4, two of them had repeat PCI and one had coronary artery bypass graft (CABG). CONCLUSION: Coronary bifurcation lesions are not uncommon. Current advances in stent technology offer a safe and effective revascularisation strategy for such complex lesions. The R(trade mark) stent appears to be a suitable device that provides good wall coverage, radial strength, conformability and easy side-branch access.     

Intravascular ultrasound assessment of culotte stent deployment for the treatment of stenoses at major coronary bifurcations

BACKGROUND: The mechanism for the disappointing late outcome following stenting of bifurcation lesions is unclear. This prospective observational study aims to evaluate culotte stent deployment and dimensions with intravascular ultrasound (IVUS). PATIENTS AND METHODS: Patients with bifurcation stenoses were treated using two stents in a culotte configuration. After optimizing the angiographic appearance of both stents, IVUS was used to evaluate both limbs of the culotte. The main outcome measures were cross-sectional area (CSA) and minimal lumen diameter (MLD) assessed by IVUS. RESULTS: Within the culotte stent, the final mean CSA in the main limb was 6.1 mm(2) (97% of reference) and in the side-limb was 5.9 mm(2) (97% of reference). However, in each case, the minimum CSA and IVUS MLD of both limbs was at the bifurcation point. For all patients, the final mean CSA at the bifurcation point of the main limb was 4.3 mm(2) (70% of main stent) and of the side-limb was 4.4 mm(2) (75% of side stent). The IVUS MLD at the bifurcation point of the main limb was 2.1 mm (78% of main stent) and of the side-limb was 2.1 mm (84% of the side stent). Importantly, this significant residual stenosis was not detectable with quantitative coronary angiography. CONCLUSIONS: IVUS evaluation of culotte stents is feasible. The minimum IVUS CSA and MLD of both limbs of the culotte stent is at the bifurcation point. Despite an optimal angiographic appearance a significant residual stenosis was noted with IVUS at each bifurcation point.     

Efficiency of medical versus endovascular treatment using drug-eluting stents in coronary heart disease patients with extensive lesion of the coronary bed

The goal of the study was to assess the long-term results of endovascular treatment using drug-eluting stents in coronary heart disease patients with extensive coronary artery lesion. The study covered 478 patients with diffuse coronary artery lesion, including 220 patients receiving endovascular treatment and 258 having medical treatment (a comparison group). The immediate angiographic results and long-term clinical efficiency of endovascular treatment using rapamycin-eluting stents were studied. The follow-up was 2 years. Repeat follow-ups were undertaken1and 2 years later. The immediate angiographic success rate of endovascular treatment for diffuse coronary artery lesions was 89.5%. The two-year follow-up showed the efficiency and expediency of endovascular treatment for extensive coronary artery lesions: the symptoms of angina pectoris occurred significantly less frequently symptoms, the exercise endurance was higher, and the need for antianginal medications was less in the invasively treated patients.     

Drug-eluting stents in the treatment of proximal vertebral artery stenosis

The objective of the study was to evaluate the efficacy of endovascular revascularization treatment using drug-eluting stents in patients with atherosclerotic proximal vertebral artery (VA) stenosis. Thirty-two patients (61 ± 10 years old) were implanted with 35 sirolimus and tacrolimus eluting stents (3 patients had them from two sides). 27 patients (84%) had vertebrobasilar symptoms at enrollment. All patients were pretreated with dual antiplatelet therapy. The intervention was technically successful in 89% cases. No stroke, myocardial infarction, or death occurred in perioperative period. On duplex scanning the stents remained completely functional. In the late postoperative period 29 (91%) patients, with 32 implanted stents were followed- up. The mean follow-up was 9.5 months. No stroke occurred in patients during this period. Recurrence of vertebrobasilar insufficiency symptoms was noted in 3 patients. VA renarrowing was detected in 16 (50%) arteries in 15 patients, and 12 (80%) of them were asymptomatic. Restenosis ≥50% (n = 13) and reocclusion (n = 3) were more frequent in those with implantation of tacrolimus eluting stents compared to those with sirolimus eluting stents: 10 (71%) of 14 observations to 6 (33%) of 18 cases (p = 0.1794), respectively. Stent fracture was observed in 2 cases (6%), followed by restenosis. Restenosis rate prevailed in men (p = 0.0173). Thus, stenting of VA extracranial portion is reasonably safe procedure with a good clinical effect. The use of drug-eluting stents looks promising but does not solve the problem of high restenosis rate in the late postoperative period.