冠状动脉支架断裂的研究进展

冠状动脉内支架断裂是冠状动脉支架术后少见而严重的并发症,支架断裂后引起支架内再狭窄和支架内血栓形成,是支架术后再次血运重建的原因之一。目前研究发现多种原因与支架断裂相关,包括右冠状动脉、病变角度、支架长度、支架重叠、静脉桥血管、Cypher支架应用等。该文主要就冠状动脉支架断裂的分类、检测方法、发生机制、临床表现及处理方法等进行综述。     

冠状动脉药物洗脱支架与支架内血栓

支架内血栓是冠状动脉支架术后少见但却严重危及生命的并发症。药物洗脱支架由于降低了再狭窄率而使冠状动脉粥样硬化性心脏病介入治疗领域发生了革命性的变化,但对其增加晚期血栓的顾虑成为目前关注的热点。支架内血栓的形成除了支架本身的致栓作用外,还与患者、病变及手术等因素相关。此外,过早中断双联抗血小板治疗、延迟再内皮化及晚期支架贴壁不良等均与支架内血栓密切相关。本文就支架内血栓的定义、发生机制及对策等进行综述。     

药物洗脱支架治疗冠状动脉支架内再狭窄的临床观察

目的观察药物洗脱支架治疗冠脉支架内再狭窄的临床疗效。方法对入选的患者行药物洗脱支架治疗,术后观察心脏不良反应事件的发生情况。结果 44例患者中发生不良反应事件22例,其中胸痛复发19例,TVR7例,ISR处原支架的类型是影响术后疗效的重要因素,本研究认为DES术后ISR的疗效好于BMS术后ISR（P=0.002）。而患者的年龄、性别、病变血管的直径和病变部位、病变的严重程度以及DES涂层材料的不同与治疗效果无明显的相关性。结论药物洗脱支架是治疗冠状动脉支架内再狭窄的有效手段。     

药物洗脱支架治疗冠状动脉支架内再狭窄的临床观察

目的观察药物洗脱支架治疗冠脉支架内再狭窄的临床疗效。方法对入选的患者行药物洗脱支架治疗,术后观察心脏不良反应事件的发生情况。结果 44例患者中发生不良反应事件22例,其中胸痛复发19例,TVR7例,ISR处原支架的类型是影响术后疗效的重要因素,本研究认为DES术后ISR的疗效好于BMS术后ISR(P=0.002)。而患者的年龄、性别、病变血管的直径和病变部位、病变的严重程度以及DES涂层材料的不同与治疗效果无明显的相关性。结论药物洗脱支架是治疗冠状动脉支架内再狭窄的有效手段。     

第一代药物洗脱支架置入术后晚期支架内血栓的病因病理

几项随机并观察性研究报告称,第一代药物洗脱支架(DES)置入5年内的晚期支架内血栓(LST)累积发生率呈稳步增长的趋势。病理学研究确定,DES后的LST主要是由于未覆盖的内皮支架梁的存在,这将导致动脉的延迟愈合,而动脉延迟愈合与长支架、重叠支架置入、分叉支架置入有关。5级支架断裂也可引起LST和再狭窄。过敏反应是雷帕霉素洗脱支架后LST独有的病因,而过度纤维蛋白沉积的贴壁不良与紫杉醇洗脱支架相关。支架内膜新生动脉粥样硬化是金属裸支架和DES后LST的另一重要因素,而其在DES中的发展更快速和常见。今后的病理研究应解决新一代DES的长期安全问题,这将有助于降低LST和改善患者预后。     

药物涂层支架预防冠状动脉再狭窄的研究进展

冠状动脉内支架植入术已经是目前应用最广泛的冠心病介入治疗技术,虽然与单纯的经皮腔内冠状动脉成形术(PTCA)相比较,支架植入术后的再狭窄率已大大降低,在局限性病变和直径>3.0mm血管的病变中,支架内再狭窄(in-stentrestenosis,ISR)的发生率大约是10％～20％,如果合并有糖尿病等危险因素,弥漫性病变或是直径<3.0mm血管的病变,则ISR的发生率高达30％～60％,所以如何降低冠状动脉内支架植入术后的再狭窄率,是一个迫切需要解决的问题。 再狭窄的发生机制主要有:①血管弹性回缩;②血管重建;③血管内皮增生。支架植入术可以防止血管弹性回缩和血管重建所引起的再狭窄的发生,但却加剧了血管内皮的增生。这是因为支架植入引起了血管损伤及排异反应,从而启动了血管壁     

药物洗脱支架和金属裸支架在急性心肌梗死中应用的对比研究进展

经皮冠状动脉介入治疗与药物治疗相比,已被证明能降低急性心肌梗死(AMI)患者的病死率和复发性缺血率。在当前介入时代,药物洗脱支架(DES)和金属裸支架(BMS)已被广泛使用。使用DES和BMS发生的病死率、心肌梗死、支架内再狭窄、支架内血栓和主要心脏不良事件成为现在研究的热点。该文主要总结使用DES和BMS对AMI患者的安全性和有效性。     

药物洗脱支架治疗冠状动脉支架内再狭窄的疗效

目的探讨药物洗脱支架治疗冠状动脉支架内再狭窄(ISR)的疗效。方法33例患者经冠状动脉造影确定为ISR,对33处ISR进行植入药物洗脱支架并随访。结果随访(19.1±4.8)月,6例有心绞痛或可疑心绞痛发作的患者中,5例复查冠状动脉造影,其中1例TAXUS支架植入术后9个月发生心肌梗死,冠状动脉造影见支架内完全闭塞,其他造影者均未发现支架内再狭窄。结论药物洗脱支架治疗ISR成功率高,长期随访结果满意。     

药物洗脱支架对糖尿病合并冠状动脉支架内再狭窄的远期效果

目的观察药物洗脱支架治疗糖尿病合并冠状动脉支架内再狭窄的远期效果。方法选取2015年6月至2017年5月西峡县人民医院收治的187例冠状动脉支架内再狭窄患者,其中合并糖尿病的75例作为观察组,未合并糖尿病的112例作为对照组。所有入选患者均接受药物洗脱支架治疗。对比两组冠脉病变情况、支架置入情况、手术成功率、1 a内再次血运重建率及治疗前后炎症因子水平。结果两组手术成功率均为100%;两组冠脉病变数、支架置入数、1年内再次血运重建率比较,差异无统计学意义(均P>0.05)。两组治疗后hs-CRP、IL-6和TNF-ɑ水平均较治疗前降低(均P<0.05),组间差异无统计学意义(均P>0.05)。结论药物洗脱支架治疗糖尿病并冠状动脉支架内再狭窄安全有效,值得临床推广。     

冠状动脉药物洗脱支架置入术后支架内再狭窄的临床研究进展

药物洗脱支架虽然很大程度上降低了再狭窄的发生率,但仍有部分患者在随访期间发生再狭窄,甚至需要再次干预病变血管。目前关于药物洗脱支架置入术后再狭窄的临床研究主要集中在预测因素、治疗上,本文就相关临床研究的最新进展作一综述。     

无聚合物药物洗脱支架与支架内血栓

药物洗脱支架(DES)明显地降低了支架内再狭窄率和靶病变重建率,但支架内血栓形成使其安全性受到质疑。导致其形成的机制及影响因素多种多样,患者的临床及病变特点、介入操作因素、抗栓治疗等都与其形成相关。药物支架所致的内皮愈合延迟、炎性反应、支架贴壁不良等为其重要机制。现对其机制、影响因素及无聚合物涂层支架在临床的应用进行综述。     

瑞典药物洗脱支架与金属裸支架的长期疗效对比

前瞻性随机临床试验已经发现．药物洗脱支架的使用与金属裸支架相比没有增加支架内血栓的形成。在包括大约4500名患者的前瞻性试验的基础上．美国食品药品监督管理局批准了药物洗脱支架在先前不能处理的一些冠脉病变的患者中的使用。在这些试验中．药物洗脱支架与金属裸支架相比表现为安全、心血管事件无显著增加。但是，药物洗脱支架的应用已经迅速扩展到所有的患者中，     

药物洗脱支架血栓形成的机制及防治进展

支架内血栓(ST)形成是经皮冠状动脉介入术治疗后少见的,但却是严重的甚至危及生命的并发症。与金属裸支架相比,药物洗脱支架已使再狭窄的发生率降低,但却使术后ST形成的发生率升高。支架内皮化不全或不内皮化是导致血栓形成的主要原因之一,如何提高支架的内皮化是临床研究的热点。研制新型抗血小板药物、提高支架置入水平,研发新型支架、基因治疗、重视冠心病的二级预防等是预防ST形成的有效措施。     

Comparison of the Efficacy of Drug-eluting Stents Versus Bare-metal Stents for the Treatment of Left Main Coronary Artery Disease

Background:

Recent studies reported that percutaneous coronary intervention with stent implantation was safe and feasible for the treatment of left main coronary artery (LMCA) disease in select patients. However, it is unclear whether drug-eluting stents (DESs) have better outcomes in patients with LMCA disease compared with bare-metal stent (BMS) during long-term follow-up in Chinese populations.

Methods:

From a perspective multicenter registry, 1136 consecutive patients, who underwent BMS or DES implantation for unprotected LMCA stenosis, were divided into two groups: 1007 underwent DES implantation, and 129 underwent BMS implantation. The primary outcome was the rate of major adverse cardiac events (MACEs), including cardiovascular (CV) death, myocardial infarction (MI), and target lesion revascularization (TLR) at 5 years postimplantation.

Results:

Patients in the DES group were older and more likely to have hyperlipidemia and bifurcation lesions. They had smaller vessels and longer lesions than patients in the BMS group. In the adjusted cohort of patients, the DES group had significantly lower 5 years rates of MACE (19.4% vs. 31.8%, P = 0.022), CV death (7.0% vs. 14.7%, P = 0.045), and MI (5.4% vs. 12.4%, P = 0.049) than the BMS group. There were no significant differences in the rate of TLR (10.9% vs. 17.8%, P = 0.110) and stent thrombosis (4.7% vs. 3.9%, P = 0.758). The rates of MACE (80.6% vs. 68.2%, P = 0.023), CV death (93.0% vs. 85.3%, P = 0.045), TLR (84.5% vs. 72.1%, P = 0.014), and MI (89.9% vs. 80.6%, P = 0.029) free survival were significantly higher in the DES group than in the BMS group. When the propensity score was included as a covariate in the Cox model, the adjusted hazard ratios for the risk of CV death and MI were 0.41 (95% confidence interval [CI]: 0.21–0.63, P = 0.029) and 0.29 (95% CI: 0.08–0.92, P = 0.037), respectively.

Conclusions:

DES implantation was associated with more favorable clinical outcomes than BMS implantation for the treatment of LMCA disease even though there was no significant difference in the rate of TLR between the two groups.     

肝素化聚氨酯作为药物洗脱支架涂层材料

以聚碳酸酯二元醇 (PCDL)为软段,4, 4′-二苯基亚甲基二异氰酸酯 (MDI)为硬段,二羟甲基丙酸(bis-MPA)为扩链剂合成了侧链含羧基的聚碳酸酯型聚氨酯。聚氨酯表面经1-乙基(3-二甲基氨基丙基)碳酰二亚胺盐酸盐(EDAC)活化后接枝肝素分子,得到肝素化聚氨酯材料。经测定,材料表面肝素接枝量达到1.92 μg/cm2,聚合物亲水性明显提高,体外蛋白质黏附实验显示肝素化聚氨酯抑制蛋白质吸附的能力较肝素化之前明显提高。动物实验表明肝素化聚氨酯作为支架涂层材料对血管壁的炎性刺激明显低于未肝素化材料,有望成为一种理想的冠状动脉支架涂层材料。     

药物洗脱支架治疗冠状动脉疾病疗效优势的研究进展

药物洗脱支架(DES)取代裸金属支架(BMS)应用于临床是心脏病介入治疗领域的突破性进展。DES的介入治疗可与冠状动脉旁路移植术(CABG)媲美,后者是目前临床上治疗冠状动脉疾病的标准方法。DES可较好控制再狭窄率的效果。此外,复杂程度较低的冠心病患者用DES进行经皮冠状动脉介入(PCI)的疗效好。但是CABG依然是左前降支或左主干冠状动脉病以及复杂的多血管病变患者优先选择的治疗方案。     

Efficacy of Short-term Dual Antiplatelet Therapy after Implantation of Second-generation Drug-eluting Stents: A Meta-analysis and Systematic Review

Objective The benefit of short-term dual antiplatelet therapy (DAPT) following second-generation drug-eluting stents implantation has not been systematically evaluated. To bridge the knowledge gap, we did a meta-analysis to assess the efficacy of≤6 monthsversus≥12 months DAPT among patients with second-generation drug-eluting stents. Methods We searched online databases and identified randomized controlled trials that assess the clinical impact of short-term DAPT (≤6 months) published before March 3, 2016. The efficacy endpoints included the incidence of all-cause death, myocardial infarction, cerebrovascular accidents, and definite or probable stent thrombosis. Safety endpoint defined as major bleeding was also evaluated and discussed. Results We included 5 trials that randomized 9473 participants (49.8%, short-term DAPT durationvs. 50.2%, standard duration). A total of 9445 (99.7%) patients reported the efficacy endpoints, and the safety endpoint was available from 4 studies (n=8457). There was no significant difference in efficacy endpoints between short-term and standard DAPT duration(≥12 months) [risk ratio(RR) 0.96; 95% confidence intervals(CI), 0.80-1.15]. Short-term DAPT duration did not significantly increase the individual risk of all-cause death, myocardial infarction, cerebrovascular accidents, or definite or probable stent thrombosis. Although short-term DAPT obviously reduced risk of major bleeding compared with standard DAPT (RR 0.53; 95%CI, 0.29-0.96), significant publication bias was found when accessing the safety endpoint of the 4 studies (Egger's test,P=0.009). Conclusions The efficacy of short-term DAPT was comparable with that of standard duration DAPT. DAPT less than 6 months may be appropriate for patients receiving second-generation drug-eluting stents implantation.     

Drug-eluting balloon: Initial experience in patients with in-stent restenosis (ISR)

Background

In-stent restenosis is the most important limitation of modern coronary angioplasty. Drug-eluting stents solve this problem but at the cost of late stent thrombosis and longer duration of dual-antiplatelet therapy. Drug-eluting balloon (DEB) technology is now available and offers an attractive option for treatment of restenosis.

Methods

A cohort of 20 patients with in-stent restenosis after stenting were treated with a drug-eluting balloon and were followed up clinically and angiographically for 6 months.

Results and conclusion

Procedural success was achieved in all patients. 6 month clinical follow-up was available for all and 6 month angiographic follow up for 17 patients. On 6 month follow-up, 5 of the 20 patients had recurrence of angina and 4 patients had angiographic restenosis (2 focal, 2 diffuse). The mean Canadian Cardiovascular Society angina score improved significantly from 3.1 to 1.1. DEB offers a novel method of treatment for patients with in-stent restenosis with a good safety and efficacy profile.