Application of rotational atherectomy in the drug-eluting stent era

Rotational atherectomy (RA) was introduced in the interventional arena in 1988 as a dedicated device for calcified lesions. Due to the complexity of the technique, the development of alternative method...     

Stent thrombosis following drug-eluting stent implantation. A single-center experience

BACKGROUND: The risk of stent thrombosis (ST) following drug-eluting stent (DES) implantation may extend beyond the initial period after successful implantation. METHODS: We evaluated the incidence, timing, and clinical outcomes of patients who presented with DES-related early (30 days) angiographic ST. Between 1/2004 and 9/2006, a total of 1339 patients underwent DES implantation (90% using Cypher stents) at our institution. Dual antiplatelet therapy was recommended for 3 to 12 months. Clinical follow-up was obtained and adjudicated at 1 and 6 months following any ST event. RESULTS: We identified eight patients (0.6% of the total patients treated with DES) with definite ST. Their mean age was 67+/-13 years. Six patients (75%) were male and 37.5% (3/8) had diabetes. Acute myocardial infarction (AMI) was the clinical presentation in 87.5% of patients. Time to ST was 4 days in two (25%) of eight patients. The other six patients (75%) had late ST (>30 days). The median time to late ST was 480 days (range: 90-1080 days). Two patients had recurrent events of late ST. All cases of late ST, except one, occurred after clopidogrel treatment was discontinued. Median time from clopidogrel withdrawal to late ST was 18 months (range: 0.5-35 months). At 6 months' follow-up from the time of ST, the subsequent major adverse cardiac event (MACE) rate (including death, re-infarction, recurrent ST or need for emergent CABG) was 62.5% and overall and/or cardiac mortality rate was 12.5%. CONCLUSION: We found that ST occurred infrequently (0.6%) and the majority (75%) of patients developed ST late (>30 days) and beyond the period recommended for dual anti-platelet pharmacotherapy. Major adverse cardiac events following ST are substantial at 6 months and thus deserve careful clinical attention.     

冠状动脉严重钙化病变旋磨术后植入药物洗脱长支架的长期临床疗效观察

目的 探讨冠状动脉（简称“冠脉”）旋磨术联合药物洗脱长支架用于治疗严重冠脉钙化病变的安全性及有效性。方法 入选2010年1月至12月因严重冠脉钙化而行冠脉旋磨术联合药物洗脱长支架植入治疗的患者。观察患者的手术成功率,围术期并发症及术后主要心血管事件（包括心源性死亡、心肌梗死、靶病变血运重建）的发生率。结果 共21例严重冠脉钙化病变患者接受了冠脉旋磨术联合药物洗脱长支架植入治疗,年龄（65.2±6.9）岁。合并高血压病16例（76.2%）,糖尿病7例（33.3%）,肾功能不全1例（4.8%）。旋磨部位共植入35枚国产药物支架（1.75枚/部位）,最短支架长度为28mm,病变部位平均支架总长度为48（29～66）mm,仅1例因旋磨头未能通过病变而放弃,手术成功率为95.2%（20/21）。术中1例出现冠脉痉挛,1例出现胸痛伴心率减慢;术后1例出现消化道出血。住院期间无心血管事件发生,平均随访26个月,仅1例（4.8%）患者于术后第2个月发生急性心肌梗死,余患者病情稳定。结论 冠脉旋磨术联合药物洗脱长支架植入术治疗严重冠脉钙化病变可取得很高的手术成功率,是治疗钙化病变安全、有效的方法。     

Rotational atherectomy followed by drug-eluting stent implantation (Rota-DES): a rational approach for complex calcified coronary lesions

Rotational atherectomy has been regaining interest over the last couple of years after it almost has disappeared from most interventional catheterization laboratories for several years due to failure to prove its original concept of improving long term results of percutaneous coronary interventions (PCI) as was repeatedly shown in studies in the 1990s. Its revival coupled the introduction of drug-eluting stents (DES); these devices have led to treating much more complex lesions and high-risk patients by PCI. However, real-world experience suggested that off-label use of DES is associated with a higher rate of early and late stent thrombosis. Therefore, more attention is now being paid to the initial implantation technique of DES including aggressive lesion preparation to facilitate stent delivery and expansion. The limited studies with rot-ablation and DES showed promising results with no long term safety concerns. In these studies, a subtle observation was made suggesting that rot-ablation prior to DES implantation in such lesions may have an add-on effect on long term outcome compared to DES alone. An ongoing multicenter study is investigating such effect among complex calcified coronary lesions. Even if this additive benefit does not prove true, rot-ablation remains an efficient tool for preparing certain lesions to facilitate effective and safe DES implantation. Therefore, interventional training programs should focus on this difficult technique to bridge the gap of experience which resulted from neglecting it for several years. In this regard, dedicated courses at experienced sites as well as medical simulation may be appropriate.     

Intravascular ultrasound in the drug-eluting stent era

Intravascular ultrasound (IVUS) has become an indispensable part of all drug-eluting stent (DES) studies; findings must be put into context with the IVUS findings in bare metal stents. Unfortunately, there is not yet a complete picture of either the Cypher (Cordis, Miami, Florida) or the Taxus (Boston Scientific, Maple Grove, Minnesota) stent (the two U.S. Food and Drug Administration-approved devices). Intimal hyperplasia volume in DES is reduced to <15% of stent volume, but stent underexpansion continues to be a consistent finding in DES failures (restenosis and thrombosis). The utility of IVUS to assure adequate stent expansion may be more important whenever there are clinical risk factors for DES failure.     

Passive stent coatings in the drug-eluting era

Advances in coronary stent technology, both in terms of stent design and function, have significantly improved the safety and efficacy of percutaneous coronary intervention, including marked reduction in restenosis. This has led to its use in increasingly challenging clinical and lesional subsets, with potential for increased risk of stent-associated thrombosis. In this article we outline the development of passive stent coatings, and evaluate the ongoing role of such coatings in the contemporary era of antiproliferative drug-eluting stents.     

In-stent restenosis in the drug-eluting stent era

The introduction of the drug-eluting stent (DES) proved to be an important step forward in reducing rates of restenosis and target lesion revascularization after percutaneous coronary intervention. However, the rapid implementation of DES in standard practice and expansion of the indications for percutaneous coronary intervention to high-risk patients and complex lesions also introduced a new problem: DES in-stent restenosis (ISR), which occurs in 3% to 20% of patients, depending on patient and lesion characteristics and DES type. The clinical presentation of DES ISR is usually recurrent angina, but some patients present with acute coronary syndrome. Mechanisms of DES ISR can be biological, mechanical, and technical, and its pattern is predominantly focal. Intravascular imaging can assist in defining the mechanism and selecting treatment modalities. Based upon the current available evidence, an algorithm for the treatment approaches to DES restenosis is proposed.     

药物洗脱支架年代支架内血栓再评估

药物洗脱支架(DES)的应用,显著降低冠心病介入治疗术后的再狭窄发生率,并改善了患者的预后.本文对DES治疗的安全性与效价比、持续性、有效性等进行评估,针对现有DES可能面临的安全性顾虑,提出应进一步改进现有DES的方向,积极开发第二代DES,提高和完善冠心病介入治疗的效果.     

Rotational atherectomy with a new device: Initial clinical experience

The Bard Atherectomy Catheter is a new rotational atherectomy device that consists of a flexible, hollow, thin-walled cutting catheter that, while rotated at 1,500 revolutions per minute, is advanced across the lesion over a special spiral guidewire system. We report the initial clinical experience with this device in 20 peripheral lesions in ten patients. The majority of patients were treated for limb salvage. All lesions were successfully intervened on by atherectomy followed by adjunctive balloon angioplasty. A reduction to less than 50% stenosis was achieved in 13 of the 20 lesions (65%) after atherectomy but in all 20 lesions (100%) after adjunctive angioplasty for all lesions and stenting for dissections in two. Baseline minimal lesion lumen diameter was 0.8 ± 0.7 mm with a reference vessel diameter of 4.2 ± 1.7 mm (75 ± 21% stenosis). The lumen improved to 2.0 ± 0.8 mm (45 ± 19% stenosis) (P < 0.001) following atherectomy and to 3.9 ± 1.9 mm (13 ± 16% stenosis) (P < 0.001) after adjunctive angioplasty. The average weight of removed atheroma was 45 ± 58 mg. All ten patients had initial improvement in symptoms. At 6 months follow-up there was persistent improvement in eight patients and two subjects had undergone amputations. Our early clinical experience with this low profile, flexible atherectomy device, that enables extraction of a large amount of atheroma, suggests that it will become a valuable addition to current atherectomy technologies in small- and medium-sized vessels. The value of this device in coronary vessels is under investigation. © 1996 Wiley-Liss, Inc.     

Restenosis treatment in the drug-eluting stent era.

Despite recent advances, the in-stent restenosis (ISR) remains a challenging problem in interventional cardiology with an estimated overall restenosis rate of 20%, 25-30% in bare metal stents and 12% in drug-eluting stents (DES). In this review, we provide an overview of therapeutic options which include balloon angioplasty, cutting balloon, debulking techniques, brachytherapy and DES. Intracoronary brachytherapy using beta or gamma radiation had been considered the standard of care for some years. However, the use of DES to treat ISR has been shown to be safe, effective and ease-of-use for the prevention of recurrent restenosis. ISR after DES when focal angiographic pattern is present can be often treated with balloon angioplasty whereas if a non-focal pattern is recognized a new DES implantation is indicated. Waiting for a definitive answer regarding the optimal treatment of ISR from ongoing trials, we present our current approach to ISR.     

Validation of predictors of intraprocedural stent thrombosis in the drug-eluting stent era

Although predictors of acute intraprocedural stent thrombosis (IPST) in the drug-eluting stent era have been proposed, external validation is lacking. We thus analyzed the occurrence of IPST in the RECIPE study and found that, among 1,320 patients who underwent drug-eluting stent implantation, IPST occurred in 6 (0.5%), with in-hospital major adverse events in 4 (67%). IPST was predicted by number and total length of implanted stents, baseline minimal lumen diameter, and, in a pooled analysis that incorporated values from the present study and a previous study, use of elective glycoprotein IIb/IIIa inhibitors. Such results may provide useful information to guide prevention of this complication.     

RESTEM: a percutaneous coronary intervention 'real world' registry in the drug-eluting stent era

Sirolimus-eluting stents (SESs) reduce the rate of in-stent restenosis in selected cases. Their performance in more complex patients and their impact on the final clinical outcome of these patients, however, remains uncertain. RESTEM Registry (REgistro delle PCI in era di STEnt Medicati), a prospective multicenter registry collecting all percutaneous coronary interventions (PCIs) performed over 20 months and monitored up to 2 years, includes 5524 consecutive patients treated with bare metal stent (BMS) (72%), sirolimus-eluting stent (SES) (15%), combined BMS+SES (4%), or other techniques (9%). The combination of death, acute myocardial infarction (AMI), unstable angina and revascularizations had been chosen as primary endpoint. One-year multivariate analysis shows no significant advantage of SES in combined clinical events, a slight benefit in primary endpoint [18.5 vs. 25.0% BMS=odds ratio (OR) 0.78) and revascularizations (13.6 vs. 20.4% BMS=OR 0.74], a consistent advantage when only target vessel revascularizations (TVRs) are considered (5.5 vs. 10.5% BMS=OR 0.52). The two-year adjusted results confirm a significant advantage of SES in TVR (8.3 vs. 13.7% BMS=OR 0.65), a slight benefit for revascularizations (18.3 vs. 25.6% BMS=OR 0.76), without reducing mortality and other clinical events; these data refute the benefit on primary endpoint observed at 12 months (25.8 vs. 32.4% BMS=OR 0.84). After analyzing events recorded during the first and second year follow-up periods separately, the incidence of many of them favors SES in the first year, yet appear independent of the technique utilized in the second. RESTEM results confirming SES's capacity to reduce TVR without reduction of other clinical events, suggest that this advantage is limited to the first year after PCI, and show no evidence of excess of deaths, AMIs and late thrombosis following SES implantation described in recent meta-analyses.