Percutaneous coronary intervention for bifurcation lesions: 2008 consensus document from the fourth meeting of the European Bifurcation Club

CTO and Bifurcation Lesions: An Expert Consensus From the European Bifurcation Club and EuroCTO Club

Knowledge in the field of bifurcation lesions and chronic total occlusions (CTOs) has progressively improved over the past 20 years. Therefore, the European Bifurcation Club and the EuroCTO Club have decided to write a joint consensus statement to share general knowledge and practical approaches in this complex field. When percutaneously treating CTOs, bifurcation lesions with relevant side branches (SBs) are found in approximately one-third of cases (35% at the proximal cap, 38% at the distal cap, and 27% within the CTO body). Occlusion of a relevant SB is not rare and has been shown to be associated with procedural complications and adverse outcomes. Simple bifurcation rules are very useful to prevent SB occlusion, and provisional SB stenting is the recommended approach in the majority of cases: protect the SB as soon as possible by wiring it, respect the fractal anatomy of the bifurcation by using the 3-diameter rule, and avoid using dissection and re-entry techniques. A systematic 2-stent approach can be used if needed or sometimes to connect both branches of the bifurcation. The retrograde approach can be very useful to save a relevant SB, especially in the case of a bifurcation at the distal cap or within the CTO body. Intravascular ultrasound is also a very important tool to address the difficulties with bifurcations at the proximal or distal cap and sometimes also within the CTO segment. Double-lumen microcatheters and angulated microcatheters are crucial tools to resolve access difficulties to the SB or the main branch.

Fundamentals of percutaneous coronary bifurcation interventions

Coronary bifurcation lesions (CBLs) account for 15%-20% of all percutaneous coronary interventions. The complex nature of these lesions is responsible for poorer procedural, early and late outcomes. This complex lesion subset has received great attention in the interventional cardiac community, and multiple stenting techniques have been developed. Of these, the provisional stenting technique is most often the default strategy; however, the elective double stenting (EDS) technique is preferred in certain subsets of complex CBLs. The double kissing crush technique may be the preferred EDS technique because of its efficacy and safety in comparative trials; however, this technique consists of many steps and requires training. Many new methods have recently been added to the EDS techniques to provide better stent scaffolding and to reduce early and late adverse outcomes. Intravascular imaging is necessary to determine the interventional strategy and postinterventional results. This review discusses the basic concepts, contemporary percutaneous interventional technical approaches, new methods, and controversial treatment issues of CBLs.

Towards a common pathway for the treatment of left main disease: contemporary evidence and future directions: Left main disease treatment

There is increasing evidence to support percutaneous treatment of left main (LM) disease. Due to its major clinical impact, any procedure in the left main should be meticulously planned and performed. In this review, we aim to integrate the available evidence into a common treatment pathway, starting with understanding the distinct anatomical features of the left main. A three-level decision-making process is presented. First, in instances of angiographic ambiguity, intravascular ultrasound and fractional flow reserve can be used to decide if revascularisation could be deferred. Second, if revascularisation is indicated, the risks and benefits of percutaneous versus surgical procedures should be evaluated. Third, if percutaneous coronary intervention (PCI) is chosen, the operator should decide between the provisional single-stent versus upfront two-stent strategies. Regardless of the PCI technique selected, it should be performed according to the recommendations of a stepwise procedure utilising proximal optimisation (POT) after each instance of crossover stenting and kissing balloon inflation (KBI) where necessary. In addition to the recognised quality markers such as POT and KBI, we discuss the clinical relevance of the operator's LM PCI experience and the intracoronary imaging guidance when treating patients with left main disease.

European Bifurcation Club white paper on stenting techniques for patients with bifurcated coronary artery lesions

BACKGROUND

Defining the optimal conduction of percutaneous-coronary-intervention (PCI) to treat bifurcation lesions has been the subject of many clinical studies showing that the applied stenting technique may influence clinical outcome. Accordingly, bifurcation stenting classifications and technical sequences should be standardized to allow proper reporting and comparison.

METHODS

The European Bifurcation Club (EBC) is a multidisciplinary group dedicated to optimize the treatment of bifurcations and previously created a classification of bifurcation stenting techniques that is based on the first stent implantation site. Since some techniques have been abandoned, others have been refined and dedicated devices became available, EBC promoted an international task force aimed at updating the classification of bifurcation stenting techniques as well as at highlighting the best practices for most popular techniques. Original descriptive images obtained by drawings, bench tests and micro-computed-tomographic reconstructions have been created in order to serve as tutorials in both procedure reporting and clinical practice.

RESULTS

An updated Main-Across-Distal-Side (MADS)-2, classification of bifurcation stenting techniques has been realized and is reported in the present article allowing standardized procedure reporting in both clinical practice and scientific studies. The EBC-promoted task force deeply discussed, agreed on and described (using original drawings and bench tests) the optimal steps for the following major bifurcation stenting techniques: (a) 1-stent techniques ("provisional" and "inverted provisional") and (b) 2-stent techniques ("T/TAP," "culotte," and "DK-crush").

CONCLUSIONS

The present EBC-promoted paper is intended to facilitate technique selection, reporting and performance for PCI on bifurcated lesions during daily clinical practice.

First in human evaluation of a novel Sirolimus-eluting ultra-high molecular weight bioresorbable scaffold: 9-, 24-and 36-months imaging and clinical results from the multi-center RENASCENT study

BACKGROUND

RENASCENT is a prospective, multi-center first-in-human clinical study to evaluate the clinical performance of the novel sirolimus-eluting 150-μm strut thickness FORTITUDE® BRS for percutaneous coronary intervention of single de novo coronary lesions.

METHODS

FORTITUDE® BRS was tested in a prospective study in Italy and Colombia. Study objectives were in-scaffold angiographic late lumen loss (LLL) measured by quantitative coronary angiography and target vessel failure (TVF) defined as the composite rate of cardiac death, target vessel myocardial infarction or ischemia driven target lesion revascularization (TLR) at 9- and 24-months with clinical results up to 36-months.

RESULTS

A total of 63 patients were enrolled. All patients underwent lesion pre-dilatation and 22 patients (34.9%) underwent post-dilatation. Clinical device and procedural success was 98.4% (62/63 patients) and 96.8% (61/63 patients) respectively. At 9-months, TVF occurred in 3/61 (4.9%) of the patients including 2 peri-procedural MI and one ischemia-driven TLR. Between 9- to 24-months, ischemia-driven TLR occurred in 3 additional patients (4.9%) including 1 patient who presented with very late ST after stopping all medications. There were no further TVF between 24- and 36-months.

CONCLUSIONS

In this multi-center prospective study, the FORTITUDE® BRS was shown to be safe and effective in the treatment of single coronary lesions with low levels of TVF and LLL at 9- and 24-months. It was shown to be clinically safe upto 36-months follow-up.

Randomised comparison of provisional side branch stenting versus a two-stent strategy for treatment of true coronary bifurcation lesions involving a large side branch: the Nordic-Baltic Bifurcation Study IV

Background

It is still uncertain whether coronary bifurcations with lesions involving a large side branch (SB) should be treated by stenting the main vessel and provisional stenting of the SB (simple) or by routine two-stent techniques (complex). We aimed to compare clinical outcome after treatment of lesions in large bifurcations by simple or complex stent implantation.

Methods

The study was a randomised, superiority trial. Enrolment required a SB≥2.75 mm, ≥50% diameter stenosis in both vessels, and allowed SB lesion length up to 15 mm. The primary endpoint was a composite of cardiac death, non-procedural myocardial infarction and target lesion revascularisation at 6 months. Two-year clinical follow-up was included in this primary reporting due to lower than expected event rates.

Results

A total of 450 patients were assigned to simple stenting (n=221) or complex stenting (n=229) in 14 Nordic and Baltic centres. Two-year follow-up was available in 218 (98.6%) and 228 (99.5%) patients, respectively. The primary endpoint of major adverse cardiac events (MACE) at 6 months was 5.5% vs 2.2% (risk differences 3.2%, 95% CI -0.2 to 6.8, p=0.07) and at 2 years 12.9% vs 8.4% (HR 0.63, 95% CI 0.35 to 1.13, p=0.12) after simple versus complex treatment. In the subgroup treated by newer generation drug-eluting stents, MACE was 12.0% vs 5.6% (HR 0.45, 95% CI 0.17 to 1.17, p=0.10) after simple versus complex treatment.

Conclusion

In the treatment of bifurcation lesions involving a large SB with ostial stenosis, routine two-stent techniques did not improve outcome significantly compared with treatment by the simpler main vessel stenting technique after 2 years.

Trial registration number

NCT01496638.

Sirolimus-eluting BiOSS LIM dedicated bifurcation stent in the treatment of unprotected distal left main stenosis

BACKGROUND

Proximal optimization technique (POT) has been proposed to adapt the conventional drug-eluting stent (DES) with the fractal anatomy of the bifurcation. However, only few DES are labeled for post-expansion beyond 5.0 mm. Furthermore, recrossing in the side branch (SB) through the main vessel (MV) stent cells may be challenging.

OBJECTIVES

To compare the sirolimus-eluting, balloon-expandable dedicated bifurcation stent BiOSS LIM DES versus the second generation DES in the treatment of distal unprotected left main coronary arteries (ULMCAs) lesions.

METHODS

Forty-two consecutive patients with distal ULMCA lesions were treated with the BiOSS LIM (BiOSS LIM group) in our center. A matched-group of patients treated with second-generation DES was selected from our database (Control group). The primary endpoint was the procedural complication rate, including (a) SB occlusion, defined as intraprocedural TIMI flow grade <3 immediately after MV stenting; and/or (b) trouble in SB access, defined as the need of ≥2 guidewires or a failure to recross in the SB trough the MV stent cells. The need of POT in the two groups was also analyzed.

RESULTS

The primary endpoint occurred in four (9.5%) patients in the BiOSS LIM group and in 13 (31%) in the Control group (p = 0.028; OR = 4.25; 95% confidence interval: 1.25-14.43). POT was performed more often in the Control group (71% vs. 35%; p = 0.004).

CONCLUSIONS

Compared to conventional DES, the BiOSS LIM stent (1) facilitates SB recrossing and (2) fits well with the fractal anatomy of the left main bifurcation.

A randomized trial comparing two stent sizing strategies in coronary bifurcation treatment with bioresorbable vascular scaffolds - The Absorb Bifurcation Coronary (ABC) trial

BACKGROUND

Limited information is available on the use of Bioresorbable Vascular Scaffold (BVS) in bifurcations involving significant side branches. When treating bifurcation disease with metal stents, the recommendation is to choose a stent diameter based on the distal main vessel diameter. Whether this sizing strategy is applicable to BVS is currently unknown.

METHODS

We randomised 37 patients undergoing elective PCI for 'false' bifurcation disease (Medina 0,1,0; 1,0,0; 1,1,0) to receive BVS based either on proximal or distal reference diameters. Optical Frequency Domain Imaging (OFDI) measurements were performed pre BVS insertion to obtain proximal and distal reference diameters and post implantation. BVS size was chosen according to the proximal or distal reference diameter as per randomisation. Implantation was performed using the PSP technique tailored to bifurcation stenting. OFDI was repeated post implantation to confirm satisfactory expansion and apposition.

RESULTS

Baseline demographics between the two groups were similar. Patients were aged 62.8 ± 3.3 years; 76% were male. Mean side branch diameter was 2.24 ± 0.13 mm. TIMI III flow in the main vessel was achieved in all cases. Side branch occlusion occurred in 1 case (2.7%). In the distal-sizing arm, there was a greater incidence of significant malapposition (>300 μm) at the proximal end of the scaffold on OCT (2.3% versus 0.8%, p 0.023). The incidence of distal edge dissections was numerically greater in the proximal-sizing group but this was not statistically significant (31.3% vs 11.8%, p 0.17).

CONCLUSION

Both proximal and distal sizing strategies have similar procedural complication rates when using the ABSORB BVS to treat coronary bifurcations. However a proximal sizing strategy is associated with less malapposition and may be preferable.

Techniques for Infrapopliteal Arterial Bifurcation Stenting

BACKGROUND

Endovascular treatment of infrapopliteal peripheral arterial disease (PAD) is an established and effective treatment strategy for patients with symptomatic PAD. Increasingly, complex infrapopliteal lesions are treated with an endovascular first approach, especially in the setting of critical limb ischemia (CLI) for limb salvage, avoiding major amputations which impact on mobility and quality of life. However, many complex infrapopliteal lesions involving the bifurcation of the tibial arteries remain challenging to treat because of recoil or acute dissection after angioplasty and may require stenting using specialized techniques.

METHODS AND RESULTS

We illustrated techniques for infrapopliteal arterial bifurcation stenting using case-based examples. The techniques covered include the single-stent, culottes, kissing, crush, and T-stenting techniques, and each is considered based on individual strengths and limitations.

CONCLUSIONS

Infrapopliteal bifurcation stenting allows complex bifurcation lesions to be treated effectively when flow-limiting complications are encountered after angioplasty.

Novel ultrahigh molecular weight amorphous PLLA bioresorbable coronary scaffold upsized up to 0.8 mm beyond nominal diameter: An OCT and histopathology study in porcine coronary artery model

OBJECTIVES

The aim of the study was to evaluate the biomechanical properties and healing pattern of novel sirolimus-eluting, ultrahigh molecular weight amorphous poly-L-lactic acid bioresorbable scaffolds (S-BRS) that have been postdilated by 0.55 and 0.8 mm beyond the nominal diameters within the pressure-diameter compliance chart range.

BACKGROUND

Due to the inherent limitations of bioabsorbable polymeric materials, overexpansion/upsizing may be very limited for some BRS such as the benchmark Absorb BVS. The unique biomechanical properties of the novel S-BRS may allow it to be safely upsized.

METHODS AND RESULTS

12 coronary arteries of 4 healthy Yucatan mini-swine underwent implantation of a novel S-BRS. Upsizing by postdilation was performed up to 0.55mm (PLUS 0.55, n = 6) or 0.8 mm (PLUS 0.8, n = 6) in a manner maintaining consistent 1:1.1 stent-to-artery, thus ensuring not only the overexpansion of the scaffold but consistent level of arterial injury. Optical coherence tomography (OCT) follow-up was performed at 28 and 90-days follow-up. There was no statistical difference between the tested groups in terms of acute recoil. OCT analysis after 28 days showed numerically lower levels of neointimal formation in PLUS 0.8 compared to PLUS 0.55 group. These results were sustained at 90-days follow-up. There was no difference in late recoil between studied groups. No scaffold discontinuation, deformation or overlapping of the struts were observed.

CONCLUSIONS

Overexpansion up to 0.8 mm of novel, high strength S-BRS is not associated with worse angiographic outcomes, neointimal formation or biomechanical issues such as scaffold discontinuation, deformation or overlapping of the struts, neither acutely nor chronically. © 2017 Wiley Periodicals, Inc.

Second-Generation Drug-Eluting Balloon for Ostial Side Branch Lesions (001-Bifurcations): Mid-Term Clinical and Angiographic Results

BACKGROUND

In the drug-eluting stent era, the best strategy to treat Medina 001 lesion remains unestablished. This is the first prospective registry assessing the efficacy and safety of the second-generation drug-coated balloon in patients with side-branch ostial lesion.

METHODS

Forty-nine patients with de novo Medina 001 lesion and associated myocardial ischemia were treated with second-generation drug-coated balloon-Dior balloon catheter (Eurocor GmbH, Bonn Germany), and prospectively included in this study. After mandatory pre-dilatation, a paclitaxel-eluting balloon was inflated for a minimum of 45 seconds. Left main bifurcation, severely calcified lesions and cardiogenic shock, were the only exclusion criteria.

RESULTS

The inclusion period was 2.7 years. Mean age was 62 ± 12 years old, 41% diabetic, 65% presented with acute coronary syndrome. The most common vessel treated was the first diagonal (50%). Pre-dilatation with a cutting balloon was used in 59%. Angiographic success was 86% (in 14% a bare metal stent was implanted because of acute recoil [n = 5] or coronary dissection more than type B [n = 2]). At a mean of 12.2 ± 2.2 months, major cardiac adverse events rate was 14.3% (1 myocardial infarction, 0 cardiac deaths, 7 target lesion revascularization). There was no thrombosis or occlusion. At a mean of 7.2 ± 1.1 months, binary restenosis was 22.5% (n = 7) with a late loss of 0.32 ± 0.73 mm.

CONCLUSION

Medina 001 lesion is an infrequent type of coronary lesion. Drug-coated balloon-Dior is a safe and technically easy therapeutic option, associated with acceptable mid-term clinical outcomes. (J Interven Cardiol 2016;29:285-292).

Bifurcation lesions involved in the recanalization process of coronary chronic total occlusions: Incidence, treatment and clinical implications

BACKGROUND

The presence of a bifurcation (BL) in the context of a coronary chronic total occlusion (CTO) represents an additional difficulty. This study analyzes the incidence of BLs in CTO recanalization, the treatment, predictors of bifurcation technical success and their clinical impact.

METHODS AND RESULTS

BLs with a side branch (SB) ≥2.0mm located proximally, distally or within the occluded segment were observed in 130 (33%) of 391 CTO. Provisional stenting was the strategy more frequently used (94%). Bifurcation success (stenosis <30% in main vessel and TIMI flow III in both branches) was achieved in 105 patients (81%). In the remaining 25 (19%), the TIMI flow at the SB was <III. Predictors of bifurcation success were baseline SB wiring (OR 0.01, 95% CI: 0.001-0.09; p<0.01), the absence of dissection across the bifurcation (OR 0.10, 95% CI: 0.02-0.49; p<0.01) and non-true BLs (OR 0.16, 95% CI: 0.04-0.68; p<0.05). Regarding in-hospital results, patients with final TIMI flow <III at the SB had a higher incidence of periprocedural MI (32% vs 4.8%; p<0.01). Subsequently, the rate of MI was higher in patients with CTO-BLs than in those without BLs. At follow-up, there were no differences in the event rate between CTO-BLs and non CTO-BLs (7.7% vs 9.5%, p=ns) CONCLUSIONS: BLs in CTO is a frequent finding and could be approached as regular bifurcations. The primary success was low and this was associated with a higher incidence of periprocedural MI. Baseline SB wiring was a powerful predictor of technical success.

Bioabsorbable vascular scaffold overexpansion: insights from in vitro post-expansion experiments

AIMS

While bioresorbable vascular scaffolds (BVS) are increasingly used in clinical practice, their behaviour when post-dilated beyond their recommended maximum overexpansion diameter remains sparsely documented. We aimed to test the overexpansion of the BVS scaffold in vitro and evaluate the impact of excessive scaffold oversizing on focal point support.

METHODS AND RESULTS

We examined the post-expansion behaviour of the bioresorbable vascular scaffold (3.0 mm and 3.5 mm Absorb BVS; Abbott Vascular, Santa Clara, CA, USA) after overexpansion with non-compliant (NC) balloons of increasing diameters. After each oversizing step, the scaffolds were measured and inspected for strut disruption using microscope and optical coherence tomography imaging. Point force mechanical measurements on single scaffold struts were also performed to evaluate the impact of excessive scaffold overstretching on focal mechanical support. 3.0 mm and 3.5 mm scaffold sizes could be post-expanded up to 1 mm above their nominal diameters without any strut fracture when deployed without an external constraining model. Importantly, when overexpansion of both scaffold sizes was repeated using a constraining silicone lesion model, only post-expansion with an NC balloon size 0.5 mm larger than the scaffold nominal sizes could be performed without strut fractures. Point force compression analysis on single struts shows that overstretched struts with fractures provided lower focal strength compared to overexpanded ring segments without fractures and normal segments expanded at nominal pressure.

CONCLUSIONS

In our experiments, only overexpansion with an NC balloon 0.5 mm larger than the BVS size was feasible for BVS deployed inside an arterial lesion model. Overexpansion of the BVS scaffold beyond recommended post-dilation limits can lead to strut disconnections and focal loss of mechanical support.

Modified flower petal technique in the treatment of Medina type 0,0,1 or 0,1,0 lesions

AIMS

The optimal strategy for patients with isolated ostial bifurcation lesions has not yet been determined. We propose the modified flower petal technique for the treatment of Medina type 0,0,1 or 0,1,0 coronary bifurcation lesions.

METHODS AND RESULTS

We selected 64 patients who had Medina type 0,0,1 or 0,1,0 coronary bifurcation lesions. Percutaneous coronary intervention (PCI) was performed with the modified flower petal technique in all patients. After PCI, all patients were followed up to nine months after the intervention. Quantitative coronary angiography (QCA) analyses were performed for both the main and the side branch at baseline, after the stent implantation and at nine-month follow-up. Twenty patients (31.2%) had ostial left anterior descending artery lesions, nine patients (14.1%) had ostial circumflex artery lesions and the other patients had isolated ostial non-left main bifurcation lesions. The procedural success rate was 100%. There was no death, myocardial infarction, subacute or late stent thrombosis at nine-month follow-up. In one patient, in-stent restenosis requiring reintervention was noted.

CONCLUSIONS

The modified flower petal technique has excellent acute results and midterm clinical outcomes in the management of Medina type 0,0,1 or 0,1,0 coronary bifurcation lesions.

3D optical coherence tomography: new insights into the process of optimal rewiring of side branches during bifurcational stenting

AIMS

We describe three-dimensional optical coherence tomography (3D-OCT) guided bifurcation stenting and the clinical utility of 3D-OCT.

METHODS AND RESULTS

Twenty-two consecutive patients who underwent OCT examination to confirm the recrossing position after stent implantation in a bifurcation lesion were enrolled. Frequency domain OCT images were obtained to check the recrossing position and 3D reconstructions were performed off-line. The recrossing position was clearly visualised in 18/22 (81.8%) cases. In 13 cases, serial 3D-OCT could be assessed both before and after final kissing balloon post-dilation (FKBD). We divided these cases into two groups according to the presence of the link between hoops at the carina: free carina type (n=7) and connecting to carina type (n=6). All free carina types complied with the distal rewiring. The percentage of incomplete stent apposition (%ISA) of free carina type at the bifurcation segment after FKBD was significantly smaller than that of the connecting to carina type (0.7±0.9% vs. 12.2±6.5%, p=0.0074).

CONCLUSIONS

3D-OCT confirmation of the recrossing into the jailed side branch is feasible during PCI and may help to achieve distal rewiring and favourable stent positioning against the side branch ostium, leading to reduction in ISA and potentially better clinical outcomes.

Percutaneous coronary intervention for coronary bifurcation disease: consensus from the first 10 years of the European Bifurcation Club meetings

The European Bifurcation Club (EBC) is an independent, non-political and informal "think tank" of scientists with a particular interest in clinical, technical and fundamental aspects of the management of coronary artery bifurcation disease. Bifurcations account for 15-20% of all percutaneous coronary interventions (PCI) and remain one of the most challenging lesions in interventional cardiology in terms of procedural success rate as well as long-term cardiac events. The optimal management is, despite a fast growing scientific literature, still the subject of considerable debate, one of the main concerns being the potential increased risk of late stent thrombosis associated with treatment complexity. The EBC was initiated in 2004 and aims to facilitate an exchange of ideas on management of bifurcation disease. The EBC hosts an annual, compact meeting dedicated to bifurcations which brings together physicians, engineers, biologists, physicists, epidemiologists and statisticians for detailed discussions. Every meeting is finalised with a consensus statement which reflects the unique opportunity of combining the opinion of interventional cardiologists with the opinion of a large variety of other scientists on bifurcation management. This year the EBC celebrates its 10-year anniversary. This consensus document represents the summary of the consensus from the last ten years of the annual EBC meetings.

Assessment of side branch predilation before a provisional T-stent strategy for bifurcation lesions. A randomized trial

BACKGROUND

A simple approach is the predominant strategy for the percutaneous coronary intervention of bifurcation lesions. Performing side branch (SB) predilation in this context is currently a matter of controversy. In this study, we assess the efficacy of SB predilatation before a provisional T-stent strategy for bifurcation lesions.

METHODS

Between February 2009 and November 2012, 372 patients with true bifurcation lesions were randomized to either predilation of the SB (n = 187) or no predilatation (n = 185) before main branch (MB) stent implantation and a subsequent SB provisional stent strategy.

RESULTS

There were no significant differences between the patient groups regarding the baseline characteristics. After MB stent implantation, the TIMI flow of the SB was higher in the patients with SB predilation: TIMI flow 0 to 1; 2 (1%) versus 18 (10%), P < .001; and TIMI flow III; 179 (96%) versus 152 (82%), P < .001. Side branch stenting rates were 4% versus 3%, P = not significant. In addition, 60 patients (32%) from the SB predilation group presented SB residual stenosis by visual inspection <50%, and TIMI flow ≥III did not require any additional treatment. The failure rate of SB rewiring, the time of rewiring, the number of wires used, and the incidence of major events were similar in both groups of patients.

CONCLUSIONS

Predilation of the SB resulted in improved TIMI flow after MB stenting and less indication to subsequently treat the SB. If rewiring of the SB is required, predilation did not hinder this maneuver.

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.

Technical Aspects of Provisional Stenting in Percutaneous Treatment of Complex Bifurcation Lesions

Drug-eluting stent (DES) implantation using the 'provisional' approach is the gold standard for percutaneous treatment of patients with unselected bifurcated lesions. Nevertheless, many operators still consider the provisional approach unsuitable for coronary patients with complex bifurcation anatomies. Yet, the provisional approach may be so differently carried out that its procedural outcome is often unpredictable. Some technical refinements may help to anticipate or manage procedural difficulties, which may occur during the management of complex patients. We sought to overview the issues related with DES selection as well as some technical points, which may increase the effectiveness of provisional stenting. In particular, the DES characteristics influencing bifurcation interventions and the technical refinements, which may be considered during a provisional stenting procedure are discussed. Indeed, main vessel stent sizing, proximal optimisation, side branch protection modality, side branch rewiring, kissing balloon and side branch rescue techniques are all pivotal to increase the safety and efficacy of the provisional strategy especially in the setting of complex anatomies and patients.

The Glider registry

BACKGROUND

Provisional stenting of the side-branch (SB) is the universally accepted gold standard while there is still controversy on the usefulness of routine dilatation of the SB ostium. Recrossing the struts of a previously deployed stent with a wire and a balloon can prove challenging and is occasionally unsuccessful, mainly because the balloon tip hits a stent strut. This prospective multicenter international registry tested the crossing ability procedural results of a new-dedicated ultrashort balloon specifically designed for side branch dilatation (Glider, TriReme Medical, Pleasanton, CA, USA).

METHODS

One hundred and twenty five patients (for a total of 131 bifurcation lesions) were enrolled in the registry between January 2009 and May 2012. The Glider was used as first choice in alternative to conventional balloon (group I, 72%) or as bail-out after unsuccessful previous attempt at crossing with small conventional low-profile balloons (group II, 28%). Postprocedural coronary artery dissections and in-hospital MACE (death, myocardial infarction and repeat revascularization) were assessed. Technical success was defined as the ability of the Glider to recross the struts of a previously deployed stent while procedural success was defined as less of residual 50% diameter stenosis at the origin of the SB with a final TIMI 3 and/or freedom from in-hospital MACE.

RESULTS

Technical success was achieved, respectively, in 92% (group I), and 83% (group II). Clinical and angiographic procedural success was achieved in 98% of the lesions. In Group II, no other balloon of the same size could cross in cases where Glider could not. A total of 13 complications were observed, including nine ostial SB dissection four of which needed a second stent on the SB, one stent loss, two severe coronary spasms, and two by thrombus formation.

CONCLUSION

The unique possibility offered by this short dedicated balloon to orientate its beveled tip provides an effective strategy for recrossing stent struts when conventional low profile balloons fail achieving greater SB ostial expansion thus reducing the incidence of strut malapposition during provisional treatment of bifurcational lesions. © 2016 Wiley Periodicals, Inc.

Placement of Tryton Side Branch Stent only; a new treatment strategy for Medina 0,0,1 coronary bifurcation lesions

OBJECTIVES

We propose a new treatment strategy of Medina 0,0,1 bifurcation lesions using a dedicated side branch stent alone (Tryton Side Branch Stent™) without additional main branch stenting, with the advantage of an optimal ostial side branch coverage without the disadvantage of an excessive amount of metal in the main branch.

BACKGROUND

Medina 0,0,1 lesions are relatively rare and there is no consensus on treatment strategy. Several previous techniques have been described, all with considerable disadvantages.

METHODS

Between October 2009 and November 2011, 12 patients with Medina 0,0,1 lesions treated with Tryton alone were included. Clinical outcomes were reported as all-cause mortality, recurrent myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), and target vessel failure (TVF; defined as the composite of all-cause mortality, MI, and TVR). Procedural success was defined as successful stent placement with residual stenosis <30%, postprocedural TIMI 3 flow, and no in-hospital TVF.

RESULTS

Mean age was 64 years. Median side branch reference vessel diameter was 2.6 [2.5-3.0] mm (median stenosis 75%). Procedural success was 100%. Median clinical follow-up duration was 868 [470-906] days with just one of the patients suffering from a late adverse clinical outcome: TLR at 427 days, resulting in TVF, TVR, and TLR rates of 8.3%.

CONCLUSION

Treatment of Medina 0,0,1 lesions with the Tryton stent alone was associated with a 100% procedural success and only one late clinical adverse event (median follow-up of 868 days). These first positive results need to be confirmed in larger prospective randomized studies.

Maximal expansion capacity with current DES platforms: a critical factor for stent selection in the treatment of left main bifurcations?

AIMS

Left main stenting is increasingly performed and often involves deployment of a single stent across vessels with marked disparity in diameters. Knowing stent expansion capacity is critical to ensure adequate strut apposition after post-dilatation of the stent has been performed. Coronary stents are usually manufactured in only two or three different model designs with each design having a different maximal expansion capacity. Information about the different workhorse designs and their maximal achievable diameter is not commonly provided by manufacturers but, in the absence of this critically important information, stents implanted in segments with major changes in vessel diameter have the potential to become grossly overstretched and to remain incompletely apposed.

METHODS AND RESULTS

We examined the differences in workhorse designs of six commercially available drug-eluting stents (DES): the PROMUS Element, Taxus Liberté, XIENCE Prime, Resolute Integrity, BioMatrix Flex and Cypher Select stents. Using micro-computed tomography, we tested oversizing capabilities above nominal pressures for the different workhorse designs of the six DES using 4.0, 5.0 and 6.0 mm post-dilatation balloons inflated to 14 atmospheres. MLD could be increased significantly in all stents, only restricted by workhorse design limitations. Minimal inner lumen diameter (MLD) achieved after two successive 6.0 mm post-dilatations of the largest design (4.0 mm stent) was 5.7 mm for the Element, 5.6 mm for the XIENCE Prime, 6.0 mm for the Taxus, 5.4 mm for the Resolute Integrity, 5.9 mm for the BioMatrix and 5.8 mm for the Cypher stent. Significant deformations were observed during stent oversizing with large changes in terms of cell opening and crowns expansion. These are affected by design structure and reveal important differences among all stents tested. Such extensive deformations may alter the functional ability of an individual stent to scaffold a lesion and prevent restenosis.

CONCLUSIONS

Stent selection based on stent model design may be critical, particularly for treatment of large artery and left main bifurcations where overexpansion is normally required to optimise results and ensure full expansion of the stent.

An intravascular ultrasound comparison of left anterior descending artery/first diagonal branch versus distal left main coronary artery bifurcation lesions

AIMS

We report the intravascular ultrasound (IVUS) analysis of plaque distribution in left anterior descending (LAD) artery/first diagonal (D1) and distal left main coronary artery (LMCA) bifurcation lesion location.

METHODS AND RESULTS

We reviewed 58 angiograms of LAD/D1 bifurcation lesions with pre-intervention IVUS of both the LAD and D1 and compared these data to a corresponding cohort (n=81) of LMCA bifurcations, dividing each bifurcation into three segments: MV (main vessel), MB (main branch distal to the carina), and SB (side branch). In the LAD/D1 cohort, D1 (SB) had less calcium and a smaller plaque burden compared to the other two segments. Continuous plaque from the LAD proximal to the carina (MV) into the LAD distal to the carina (MB) was seen in 90%, from the MV into the SB in 72%, and from the MV into both the MB and SB in 62%. In the LMCA cohort, ostial left circumflex (LCX) (SB) had less calcium and a smaller plaque burden compared to the distal LMCA (MV) and ostial LAD (MB). Continuous plaque from MV to MB was seen in 96%, from MV to the SB in 78%, and from MV to both branches in 74%.

CONCLUSIONS

The IVUS analysis of the LAD/D1 and LMCA bifurcations revealed that most lesions had diffuse plaques extending from the MV into the MB with the SB having the least amount of calcium and the smallest plaque burden, regardless of location.

Optical coherence tomography for guidance of distal cell recrossing in bifurcation stenting: choosing the right cell matters

AIMS

The aim of this study was to assess the ability of optical coherence tomography (OCT) to guide recrossing during percutaneous coronary interventions in bifurcations and to reduce strut malapposition.

METHODS AND RESULTS

Fifty-two patients undergoing elective treatment of bifurcation lesions using provisional stenting as default strategy were included in the study. Patients were divided into two groups: OCT-guided stent recrossing (group 1, n=12), and angiography-guided recrossing (group 2, n=40). Malapposition in the various bifurcation segments was compared in the two groups, using propensity score analysis to correct for confounders. In 4/12 patients (33%) of the OCT-guided group after the first attempt to recross the stent towards the SB the wire was found to have crossed in a proximal cell, requiring a second and in one case a third attempt to successfully cross through a distal cell. Patients who were treated using OCT-guided recrossing had a significantly lower number of malapposed stent struts, especially in the quadrants towards the SB ostium (9.5%[7.5-17.4%] vs 42.3%[31.2-54.7%] in the angiography-guided group, p<0.0001).

CONCLUSIONS

The rate of strut malapposition was significantly reduced when OCT was used to confirm that wire recrossing was performed in a distal cell of the SB ostium.