Extension Distance Mismatch—An Unrecognized Factor for Suboptimal Side Branch Ostial Coverage in Bifurcation Lesion Stenting

Background: The unsatisfactory side branch (SB) ostial strut coverage remains a problem in coronary bifurcation stenting. Both the surplus and lack of struts at SB ostium may be the causative mechanism. We propose that the inability of available stents to cover the “extension distance” of the bifurcation region is the cause of in‐stent restenosis. Methods: The extension distance (ED) is defined as the maximal distance at the carina tip, which must be covered by the stent struts to ensure optimal coverage of the main branch (MB) and SB openings. A mathematical model was created, representing the key factors that govern geometrical reconfigurations after stent implantation in bifurcations. There are two options—with and without bifurcation region deformation. The theoretical assumptions were tested on a bifurcation model (soft polyvinylchloride polymer tubes) permitting free wall deformations and the following parameters: Parent Vessel, MB, SB diameters of 3.5, 3.0, and 2.5 mm, respectively, with an angle of 45° between the MB and SB. After stenting, final KBI with 3.5 mm and 3.0 mm balloons was performed up to 20 atm. Results: After the carina displacement, the ED, which has to be covered, is considerably smaller if the suboptimal result (DS >50%) at the SB ostium is acceptable. The maximal EDs from the bench test measurements are: Vision, Abbott Vascular – 5.62 mm ± 0.04; Liberte, Boston Scientific Corp. – 5.2 mm ± 0.03; Chopin2, Balton – 4.58 mm ± 0.05; Volo, Invatec – 4.41 mm ± 0.04; Driver, Medtronics – 4.39 mm ± 0.04; BxSonic, Cordis, J&J – 4.48 mm ± 0.05. The theoretical maximal ED of the model is 6.91 mm—28–62% larger than actually observed with different stents. Conclusions: The achievement of perfect ostial coverage of the SB is unsatisfactory with most of the currently available stents, especially when poststenting excessive dilation of the ostium of the SB is performed. (J Interven Cardiol 2010;23:305–318)     

应用双药物洗脱支架治疗分叉病变的近远期临床疗效

目的探讨应用双药物洗脱支架（DES）治疗分叉病变的临床疗效。方法选择分支开口有严重狭窄且分支口径≥2．50mm的分叉病变患者为本研究的入选对象。2003年10月至2005年6月共入选应用双DES治疗分叉病变的患者112例,113处病变。分叉病变的类型为前降支／对角支62例（54．9％）,左冠状动脉主干分叉病变32例（28．3％）,回旋支／钝缘支18例（15．9％）,右冠状动脉远端分叉病变1例。113处分叉病变中采用Crush技术64处,“T”型支架置入27处;改良“Y”型支架置入11处;对吻支架置入5处;“V”型支架置入和Culotte技术置入各3处。结果入选112例患者113处分叉病变中（226处病变）使用Cypher或Cypher select DES 91个,TAXUS DES 74个,Firebird DES 67个。64处分叉病变采用Crush技术置入双支架后60处（93．7％）完成了最后的对吻球囊扩张技术。手术成功率为100％。住院期间1例发生亚急性血栓致急性心肌梗死（AMI）,再次介入治疗成功。住院期间心脏事件发生率（MACE,包括死亡、AMI、再次血管重建）为0．89％（1／112）。112例均完成了9个月的临床随访,无死亡发生,1例发生AMI由晚期血栓形成所致。48例完成了9个月的冠状动脉造影随访（42．9％）,8例发生了支架内再狭窄,其中1例进行了冠状动脉旁路移植术,5例再次行介入治疗,总再狭窄发生率为16．7％（8／48）。随访期间MACE发生率为8．04％（9／112）。结论本研究结果显示对于分支口径≥2．5mm且口部有严重狭窄性病变的分叉病变,采用双DES治疗是安全的,近、远期临床疗效是满意的。与Cypher DES相比较,TAXUS DES的再狭窄发生率有增加的趋势。     

Single String Technique for Coronary Bifurcation Stenting: Detailed Technical Evaluation and Feasibility Analysis

ObjectivesThe study aimed to evaluate the adequacy and feasibility of the single string bifurcation stenting technique.BackgroundDouble-stent techniques may be required for complex bifurcations. Currently applied methods all have their morphological or structural limitations with respect to wall coverage, multiple strut layers, and apposition rate.MethodsSingle string is a novel method in which, first, the side branch (SB) stent is deployed with a single stent cell protruding into the main branch (MB). Second, the MB stent is deployed across this protruding stent cell. The procedure is completed by final kissing balloon dilation. The single string technique was first tested in vitro (n = 20) and next applied in patients (n = 11) with complex bifurcation stenoses.ResultsAll procedures were performed successfully, crossing a single stent cell in 100%. Procedure duration was 23.0 ± 7.9 min, and the fluoroscopy time was 9.4 ± 3.5 min. The results were evaluated by optical coherence tomography, showing fully apposed struts in 83.0 ± 9.2% in the bifurcation area. Residual area obstruction in the MB was 6.4 ± 5.6% and 25.0 ± 16.9% in the SB, as evaluated by micro computed tomography. All the human cases were performed successfully with excellent angiographic results: the residual area stenosis was 27 ± 8% and 29 ± 10% in the MB and in the SB, respectively, by 3-dimensional quantitative coronary angiography. No relevant periprocedural enzyme increase was observed. During follow-up (6 ± 4 months), no adverse clinical events (death, myocardial infarction, target vessel revascularization) were noted.ConclusionsThe single string technique for complex bifurcation dilation was shown to be adequate in vitro and feasible in humans, with favorable results in terms of stent overlap, malapposition rate, and low residual obstruction in both the MB and SB.     

Drug-Eluting Stent Restenosis: Incidence, Predictors, Mechanisms, and Treatment

Drug-eluting stents (DES) represent a major advance in percutaneous coronary intervention (PCI). Clinical trials have shown significant reductions in restenosis with both sirolimus- and paclitaxel-eluting stents, with subsequent revascularization rates in the single digit range in most studies. Predictors of restenosis and target lesion revascularization include diabetes, prior restenosis, smaller post-PCI minimal lumen diameter and complex lesion features, such as long lesions, smaller vessels, ostial lesions, and bifurcations. DES restenosis is most commonly focal (or multifocal) within the stent and less commonly is manifest as a diffuse or proliferative narrowing. The mechanisms of DES include stent under-expansion, nonuniform stent strut distribution or stent malapposition, polymer disruption due to difficult stent delivery, stent fracture, and possibly drug resistance or failure. Although only limited data are available regarding treatment of DES restenosis, reintervention appears to be associated with relatively low subsequent recurrence rates and repeat DES implantation is generally accepted as the treatment of choice for DES restenosis.     

Relative dependence of diameters of branches in coronary bifurcations after stent implantation in main vessel--importance of carina position

BACKGROUND AND AIM: Bifurcation lesions are relatively frequently encountered in everyday interventional practice. Stenting of the vessel chosen to be main (usually the larger one) frequently leads to stenosis at the ostium of the side branch (SB) and compromises its flow (side branch compromise--SBC). The relative dependence of main and side branch diameters, based on the concept of carina displacement of stent struts, was examined in a cohort of patients with bifurcation stenting. METHODS: We accept that the basic mechanism for SBC after stent placement in the parent vessel is carina shifting from expanded stent struts. The ostial SB minimal lumen diameter (MLD), percentage diameter stenosis (%DS) at maximal and calculated actual carina displacement, as well as distal limb diameter (DLD) in the main branch were calculated and compared with actually observed values. RESULTS: A group of 55 consecutive patients with acceptable quality angiograms formed the study population. General patient characteristics were similar to other bifurcation studies. Left anterior descending artery was predominantly treated in 73% of patients. There was worsening SB ostial stenosis after stent implantation (%DS increase from 48%+/-23% to 69%+/-21%, p <0.001) and final improvement because of kissing balloon inflation or SB postdilatation (post vs. final-69+/-21% and 53+/-25%, p<0.001). Stent implantation causes straightening of the main vessel, evident from a significant increase in angle C (pre- 148 degrees +/-19 degrees vs. 156 degrees +/-16 degrees after stenting, p=0.007). Relations between observed and predicted values for main branch DLD and %DS demonstrated a good correlation between predicted and observed values (for DLD r=0.66, p<0.001, and for %DS r=0.53, p <0.001). There was an excellent fit of regression lines between theoretical predictions and actual measurements for side branches (MLD r=0.91, p<0.001, %DS r=0.89, p<0.001).CONCLUSIONS: Carina displacement from stent struts is a major mechanism governing changes in coronary bifurcations after main vessel stenting. Improvement in the ostium of the side branch causes shifting back of the carina and a decrease of main vessel diameter. The long-term consequences of this phenomenon are not currently known.     

3‐year follow‐up of 100 consecutive coronary bifurcation lesions treated with Taxus stents and the crush technique

Objectives : To determine the 3 year safety and efficacy of crush‐stenting with paclitaxel‐eluting stents. Background : The optimum two‐stent strategy for treatment of coronary bifurcation lesions is undetermined. Crush‐stenting is advocated to minimize restenosis through complete circumferential stent coverage; long‐term follow‐up data are lacking. Methods and Results : In a single center prospective registry, 100 consecutive patients with bifurcation lesions were treated with the Crush technique. The vast majority (93%) were true bifurcations, predominantly involving the left anterior descending and diagonal arteries. Technical success was 98%. Final kissing balloon dilatation, which became standard practice during the study, was attempted in 68 patients and successful in 51. Abciximab was used in all cases. There were no peri‐procedural stent thromboses. Follow‐up was 100% at 3 years. Symptom‐driven target lesion revascularisation was 8% at 3 years. Cumulative 3‐year major adverse cardiac events was 28% (7 cardiac deaths, 15 myocardial infarctions, 11 target vessel revascularisations). Absence of a final kissing inflation predicted repeat revascularisation but not death, infarction or stent thrombosis. Three probable stent thromboses occurred, of which two were very late. Conclusion : Where a two‐stent bifurcation strategy is required, Crush‐stenting with paclitaxel‐eluting stents is safe and effective in the long‐term. Failure to perform a final kissing dilatation increases the likelihood of revascularisation but not other adverse events. © 2009 Wiley‐Liss, Inc.     

The AST petal dedicated bifurcation stent: first-in-human experience.

The aim of this first-in-human study was to evaluate the feasibility and safety of the novel AST petal side-access bifurcation stent. Outcomes following percutaneous coronary intervention for bifurcations remain inferior to those of nonbifurcated lesions. Even with drug-eluting stents, restenosis occurs especially at the side-branch (SB) ostium. The petal stent uniquely deploys strut elements into the SB, supporting the ostium and carina. The primary endpoint of this 13-patient prospective registry was in-hospital major adverse cardiac events (MACE). Secondary end points included acute minimum lumen diameter (MLD) at the SB ostium, lesion success, device success, procedural success, 30-day MACE, and 4-month SB ostial MLD. The study lesion was successfully treated in 13 patients with the study stent being successfully implanted in 12. Target lesions were left anterior descending coronary artery in nine subjects, left circumflex in three, and right coronary artery in one. In-hospital MACE were limited to two non-Q-wave myocardial infarctions. In-stent main branch MLD increased from a mean of 0.63 +/- 0.45 mm to 2.61 +/- 0.47 mm at the index procedure and for this initial bare metal version of the stent, 4-month mean MLD measured 1.02 +/- 0.42 mm and there was target vessel revascularization on two patients. The feasibility of safely deploying this first-generation petal stent was demonstrated in selected patients with challenging coronary bifurcation lesions. It is a promising platform for drug delivery, with unique scaffolding of the side-branch ostium.     

Evaluation of a Bifurcation Drug‐Eluting Stent System versus Provisional T‐Stenting in a Perfused Synthetic Coronary Artery Model

Background: Provisional T‐stenting is a widely used strategy for the treatment of coronary artery bifurcation lesions. However, the use of conventional stents in this setting is limited by multiple factors; this includes technical considerations such as wire wrap when accessing the involved vessel, and stent overlap at or near the carina of the lesion. In addition, current slotted tube stent technology tends to be associated with gaps in the coverage of the side branch ostium, which may result in restenosis in that segment of the lesion. The Pathfinder device, now more commonly referred to as the Xience Side Branch Access System (Xience SBA) is a drug‐eluting stent (DES) designed specifically to assist in the treatment of bifurcation lesions by allowing wire access into the side branch, irrespective of the treatment strategy to be employed. Methods: The Xience SBA drug‐eluting stent was compared with the standard Vision coronary stent system using a provisional T‐stenting strategy in a perfused synthetic model of the coronary vasculature with side branch angulations of 30°, 50°, 70°, and 90°. Stent delivery was performed under fluoroscopic guidance. Following the procedure, high‐resolution 2D Faxitron imaging was used to evaluate deployment accuracy of the side branch stent relative to the main branch stent. Results: Deployment of the Xience SBA was accomplished in the same total time as the standard stents in a provisional T‐stenting approach (14.9 vs. 14.6 minutes). However, the time required to achieve stent deployment in the main branch was less with the Xience SBA (4.0 vs. 6.6 minutes), and as a result, total contrast usage (49.4 vs. 69.4 cm³) and fluoroscopy time (5.1 vs. 6.2 minutes) was lower. Additionally, the Xience SBA had a lower incidence of wire wrap (22% vs. 89%) and less distal protrusion of the side branch stent into the main branch (0.54 vs. 1.21 mm). Significant gaps in ostial side branch coverage were not seen in either group. Conclusions: The Xience Side Branch Access DES is a viable device for consistently accessing coronary bifurcation lesions; it allows for easy wire access into the side branch. This may assist the operator in overcoming those well‐recognized limitations associated with use of standard one‐ or two‐stent strategies. In this perfused synthetic coronary model, Xience SBA deployment required less contrast usage and shorter fluoroscopy times. Further testing of this device is warranted.     

Drug-eluting stents for coronary bifurcations: bench testing of provisional side-branch strategies.

The objective of this study was to bench-test provisional bifurcation stenting strategies to provide insights on how best to perform these with drug-eluting stents (DESs). Bifurcation stenting with DESs reduces restenosis compared with bare metal stents (BMSs). Outcomes with a single DES are better than with two DESs but if the main branch is stented, there needs to be a reliable strategy for provisionally stenting the side-branch with full ostial scaffolding and drug application. Stents were photographed in a phantom after deployment with different strategies. With provisional T-stenting, placement of the side-branch stent without gaps is difficult. The internal (or reverse) crush strategy fully scaffolds the side-branch ostium but is experimental. The culotte technique providing excellent side-branch ostial coverage is easier to perform with open-cell or large-cell stent design. In general, kissing balloon post-dilation improves stent expansion, especially at the ostium, and corrects distortion. However, a main-branch kissing balloon of smaller diameter than the deploying balloon causes distortion. Final main-branch postdilatation or sequential postdilatation prevents distortion after the internal crush strategy.     

应用双药物洗脱支架治疗分叉病变的近期临床疗效

目的探讨应用双药物洗脱支架（DES）治疗分叉病变的临床近期疗效。方法自2003年10月至2005年2月入选应用双DES治疗分叉病变患者71例,72处病变。分叉病变的类型为前降支／对角支45例（62．5％）,左冠状动脉主干分叉病变20例（27．8％）,回旋支／钝缘支6例,右冠状动脉远端分又病变1例。72处分叉病变中采用Crush技术42处,包括标准Crush技术16处和改良Crush26处;“T”型支架置入19处;改良“Y”型支架置入5处;“V”型支架置入3处和Culotte技术3处。结果入选71例患者中男性59例（83．1％）,女性12例,平均年龄57岁。72处分叉病变中（144处病变）使用Cypher或Cypher Select DES 59个,TAXUS DES48个,Firebird DES 25个和金属裸支架24个。72处分叉病变置入双支架后60处（83．3％）完成了对吻球囊扩张技术。手术成功率为100％。住院期间1例发生亚急性血栓致急性心肌梗死（AMI）,再次经皮冠状动脉介入治疗成功。住院期间主要心脏不良事件（MACE,包括死亡、AMI、再次血管重建）发生率为1．4％（1／71）。71例中16例完成了6个月的临床随访,无死亡和AMI发生,1例6个月时冠状动脉造影显示对角支口部完全闭塞,随访期间MACE发生率为6．3％（1／16）。结论本研究结果显示对于分支口径〉2．5mm且口部有严重狭窄性病变的分叉病变,采用双DES治疗是安全的,近期临床疗效十分满意,远期临床疗效初步显示也是满意的,但仍有待进一步证实。     

Coronary bifurcation stenting. Current techniques, outcome and possible future developments

Percutaneous treatment of coronary bifurcation lesions remained challenging in the stent era, with restenosis rates greater than 30% and no advantage from the routine use of kissing stents. Drug eluting stents (DES) have dramatically reduced the restenosis rates (RR) in the main vessel, but with conventional T-stenting double digits figures are still reported for the side-branch because of poor ostial coverage. The techniques of kissing stenting able to provide full lesion coverage (Culotte, V-stenting, Crush) have the potential to improve these results but the development of dedicated DES is probably needed to obtain consistently high procedural and long-term success.     

Strategies for drug‐eluting stent treatment of bifurcation coronary artery disease in the United States: Insights from the e‐Cypher S.T.L.L.R.Trial

Objectives: Our goal is to report the first large multicenter data for percutaneous coronary intervention (PCI) of bifurcation disease with drug‐eluting stents (DES) in the United States. Background: Bifurcation PCI remains a challenge to this date. There are limited data on outcomes of patients treated with bifurcation DES implantation, particularly in the United States. Methods: There were 161 patients with bifurcation disease [side branch (SB) ≥2‐mm] treated with ≥1 sirolimus‐eluting stents at 41 centers participating in the Stent deployment Techniques on cLinicaL outcomes of patients treated with the cypheR?stent (STLLR) trial. There was no protocol mandated strategy for bifurcation PCI. One‐year outcome data were collected. Angiographic and clinical data were adjudicated independently. Results: There were 147 patients (91.3%) treated with single stent strategy. Only 14 (8.7%) patients received sirolimus‐eluting stents implantation in both branches. Among patients with single stent strategy, double wire strategy (DW) was selected in 27 (18.4%) patients whereas single wire strategy (SW) was selected in 120 (81.6%) patients. There were 48 (32.7%) Medina 1,1,1 bifurcations treated with SW (n = 34; 70.8%) and DW (n = 14; 29.2%). There were 26 procedures started with SW which had SB dilatation during the procedure, one as a bailout (TIMI‐1 grade flow in the SB). Overall 1‐year death, myocardial infarction, and target lesion revascularization occurred in 2.4, 4.0, and 5.6%, respectively. There was no significant difference in clinical outcomes between SW and DW. SB dilatation was associated with a high rate of stent thrombosis (8.6%). Conclusions: Main branch stenting without SB protection is the most common approach utilized in the STLLR study, which may reflect contemporary DES bifurcation strategies in the Unite States. This strategy was associated with an acceptable low incidence of adverse outcomes at 1‐year. © 2009 Wiley‐Liss, Inc.     

Coronary Left Main and Non‐Left Main Bifurcation Angles: How are the Angles Modified by Different Bifurcation Stenting Techniques?

Background: Investigation of the correlation between bifurcation angles and outcomes is limited with discordant results. The aim of this study is to investigate left main (LM) and non‐left main (N‐LM) bifurcation angles and their modification after percutaneous coronary intervention (PCI). Measurement of all three angles adds to our understanding of bifurcation anatomy and the resultant effect of different stenting techniques. Methods and Results: All three bifurcation angles were described according to the European Bifurcation Club definition: the A (proximal bifurcation angle), the B (distal bifurcation angle) and the C (main branch angle). Measurements were performed in 75 LM and 140 N‐LM bifurcations. In LM bifurcations baseline mean values of C, A, and B were 151°± 28°, 131°± 32°, and 78 ± 28°, respectively. In bifurcations with 2 stents the B significantly decreased by a mean of 10° (P = 0.003) and A increased by 10° (P = 0.006). Crush stenting significantly decreased B (A – 14°; P = 0.020) and increased A (A + 21°; P = 0.005), particularly non‐true bifurcations. In N‐LM bifurcations mean values for C, A, and B were 156°± 19°, 144°± 22°, and 60°± 20°, respectively. Similar to LM bifurcations, the B became narrower mainly at the expense of the A, which became wider. In both types of bifurcations the greatest variation in A and B was found following 2‐stent techniques performed in T‐shaped (≥70°) bifurcations. Conclusions: In both LM and N‐LM bifurcations we found a significant difference in A and B pre‐ and post‐PCI. This difference was driven by the 2‐stent technique and was most evident with a baseline bifurcation angle ≥70°. The Crush technique caused the largest angle variation post‐procedure, particularly in non‐true LM bifurcations. (J Interven Cardiol 2010;23:382–393)     

The Carina Angle—New Geometrical Parameter Associated with Periprocedural Side Branch Compromise and the Long‐Term Results in Coronary Bifurcation Lesions with Main Vessel Stenting Only

Background: The two main problems unresolved in coronary bifurcation stenting are periprocedural side branch compromise and higher restenosis at long term. The purpose of this study is to reveal the link between periprocedural side branch compromise and long‐term results after main vessel stenting only in coronary bifurcations. Methods: Eighty‐four patients formed the study population. The inclusion criteria were good‐quality angiograms, with maximal between‐branch angle opening, no overlap, permitting accurate angiographic analysis. Carina angle (α)—the distal angle between main vessel (MV) before bifurcation and side branch (SB)—was measured pre‐ and poststenting. Clinical follow‐up 9–12 months was obtained with coronary angiography if needed. Results: The patient population was high‐risk with 33% diabetics and 84% two‐ and three‐vessel disease. Ninety‐five stents were implanted in 92 lesions, with three T‐stenting cases. Drug‐eluting stents were implanted in 54%. Kissing‐balloon (KBI) or sequential inflation was performed in 35%. SB functional closure occurred in 17.4%, with independent predictors α < 40° and diameter ratio MB/SB >1.22. After 12±4 months there were five myocardial infarctions (6%) and 13 (15%) target lesion revascularization procedures. Independent predictors of major cardiovascular events were carina angle <40°, MB lesion length >8 mm, negative change of between‐branch angle, DES usage, and KBI. Conclusions: Smaller carina angle with straightening of MV—main branch from stent implantation in coronary bifurcations predicted higher SB compromise, restenosis, and MACE rates during follow‐up of 1 year.     

Treatment of a double-bifurcation lesion with sirolimus-eluting stents using the "sleeve technique"

We describe a diabetic patient with a very long lesion in a small and diffusely diseased left anterior descending artery that had 2 sizable and diseased diagonal branches (double-bifurcation lesion). The authors successfully used sirolimus-eluting stents and the sleeve technique to reconstruct the vessel and its 2 bifurcations. The sleeve technique is a modified version of the crush technique. It involves stent placement in the side branch ostium, balloon-crush of the proximal protruding stent segment against the main vessel wall, and reconstruction of the side branch ostium by kissing balloon inflation, followed by stenting of the main vessel and reconstruction of the bifurcation again by a second kissing balloon inflation.     

Résultats immédiats et à long terme après angioplastie coronaire avec stents actifs de lésions de bifurcation par la technique du « crush stenting »

The most common approach in the treatment of bifurcation lesions is stenting only the main branch (MB) with provisional T-stenting of the side branch (SB). However, some bifurcation lesions may have extensive disease within a large SB requiring stenting of this vessel. The “crush” technique, which has been proposed as an alternative approach to other strategies to treat complex bifurcations, is a relatively simple technique that ensures complete coverage of the SB ostium. Previous series have reported its safety and feasibility, but limited data are available about the long-term outcomes. We report our experience on 21 consecutive patients (pts) treated with the “crush” technique with drug-eluting stents (DES) between November 2005 and March 2007. Clinical follow-up was 18 ± 7 months for 19 pts (90%), and angiographic follow-up was completed in 66% of pts (N = 14), at a mean time of 8.5 ± 4 months. Mean pt age was 70 ± 11 years; 33% (N = 7) had diabetes mellitus, and mean preoperative logistic EUROSCORE predicted 11% mortality rate. The left anterior descending artery/diagonal and the distal left main were the most frequent bifurcation locations (52 and 43% of cases respectively), with a type 1,1,1 of the Medina classification of bifurcation lesions in 62% of pts, and an angulation MB-SB below 50° in 66% of cases. Final kissing balloon dilation was performed in 90% of pts (N = 20). Stent diameter and length were similar between MB and SB. The procedure was successfull in 100% of cases in the MB and 95% of cases in the SB. Procedure-related CK elevation above 2 ULN was seen in two pts (9.5%), without ECG modification. One pt had subacute stent thrombosis 5 days after his procedure. At the end of follow-up, target vessel revascularization (TVR) was required in four pts (19%), and target lesion revascularisation (TLR) in three pts (14%) whom had focal restenosis in the SB ostium (one pt) and in the MB and SB ostia (one pt). Sudden death occurred in one pt 14 months after his procedure. In conclusion, when an effective strategy for stenting both branches is planned, the “crush” technique with final kissing balloon can be safely used by experienced operators to treat complex bifurcation lesions with DES. The safety profile and TLR rate in our small series of “crush” stenting were similar to that of other studies reported thus far.     

The glider balloon: A useful device for the treatment of bifurcation lesions

Background

Final kissing balloon dilatation (FKBD) is a recommended final step in case of treatment of bifurcation lesions by two stents approaches. Furthermore, dilatation of the side branch (SB) may be necessary following main vessel (MV) stenting. Occasionally, recrossing the stent struts with a balloon is hampered because the tip hits a stent strut.

Methods

The Glider (TriReme Medical, Pleasanton, CA) is a dedicated balloon designed for crossing through struts of deployed stents toward a SB. From October 2010 to January 2012, FKBD was attempted in 236 consecutive bifurcation lesions treated in our Institution. FKBD was successfully performed by conventional balloon catheters in 221 (93.5%) lesions (Conventional group). In the remaining 15 (6.5%) lesions, where a conventional balloon failed to cross the stent strut, the Glider balloon was attempted (Glider group).

Results

The angle beta (between the axis of the MV after the branch point and the SB axis at the point of divergence) was wider in the Glider group (83 ± 17° versus 65 ± 27°; p = 0.032). A trend toward an higher rate of the true bifurcation lesions was observed in the Glider group (93% versus 70.5%; p = 0.07). The Glider balloon successfully crossed through MV stent struts toward a SB in 12 patients (80%), whereas failed in the remaining 3 patients.

Conclusions

The Glider balloon represents an unique bail-out device which offers an effective rescue strategy for recrossing stent struts during complex bifurcation stenting.     

Thin and crush: The new mantra in left main stenting?

Complex bifurcations have been suggested to be better approached by a planned double stent technique; however, recent randomized trials have shown better outcomes of provisional compared to planned twostent strategy, in terms of both short-term efficacy and safety. In left main(LM) bifurcations, double kissing(DK)-Crush has demonstrated its superiority over Culotte and provisional-T in terms of restenosis and stent thrombosis, gaining respect as one of the most performant techniques for bifurcations stenting. On the other hand, the Nano-Crush technique has recently become part of the repertoire of double stenting techniques, providing evidence that the use of ultrathin strut stents and very minimal crush would be beneficial for both the physiological and rheological properties of the complex bifurcations, even in LM scenario, leading to a lower rate of thrombosis and restenosis at both side branch and true carina. Finally, the newest generation of ultrathin strut stents are gaining a reputation for its safe and effective use in LM treatment thanks to improved design with increased expansion rate capable of LM treatment up to 5-6 mm diameter. The modern crush techniques, such as DK-Crush and Nano-Crush, are providing excellent results on mid and long-term follow up, suggesting that minimal crushing obtained using ultra-thin stents is a good way to obtain surgical-like outcomes in the treatment of complex LM bifurcation disease.