Inflation Pressure in Side Branch during Modified Jailed Balloon Technique Does Not Affect Side Branch Outcomes

Objectives

This study aimed to investigate the optimal jailed balloon inflation in the side branch during the modified jailed balloon technique for bifurcated lesions.

Background

The modified jailed balloon technique is one of the effective techniques to minimize the emergence of side branch (SB) compromise by preventing plaque or carina shifting during a single stent strategy in the main vessel with provisional SB treatment. However, there are no detailed studies on the method of optimal jailed balloon inflation.

Methods

We analyzed 51 consecutive patients who underwent percutaneous coronary intervention (PCI) for bifurcated lesions with a modified jailed balloon technique between September 2018 and December 2020. These 51 patients were divided into two groups according to the magnitude of inflation pressure of the jailed balloon: a higher pressure (HP) group and lower pressure (LP) group.

Results

No significant differences in procedural outcomes were observed between the two groups. The findings of SB compromise were relatively common with our procedure (30.0% in the HP group; 33.3% in the LP group). The patterns of SB compromise such as dissection or stenosis increase were observed at similar frequencies between them. In particular, SB dissection was noted in the SB lesion with some plaque burden, irrespective of the magnitude of the jailed balloon inflation pressure. Univariate analysis showed that calcification in the main vessel and SB lesion length was significantly associated with SB compromise. Finally, all PCI procedures were successfully completed without any provisional stent deployment in SB.

Conclusions

We speculate that lesion characteristics rather than the PCI procedural factors may be critical determinants to cause SB compromise.

Streamlined reverse wire technique for the treatment of complex bifurcated lesions

Inserting a guidewire into an extremely angulated side branch (SB) is difficult. Reverse wire technique (RWT) method was developed to specifically overcome this challenging situation, and it has become common among operators performing percutaneous coronary intervention. The first step of RWT involves the delivery of a reverse wire (RW) beyond the bifurcation, together with dual lumen catheter (DLC). This step is sometimes difficult, due to the stenosis proximal to bifurcation. Balloon dilatation of the stenosis is sometimes required to make space for the RW passage, but this lesion modification involves a potential risk of vessel damage, plaque shift, or carina shift, which results in the occlusion of the target SB. Streamlined RWT is a novel method we developed to facilitate RW delivery. It consists of the following three steps: (a) Advancing a DLC alone beyond the occlusion and inserting a preshaped RW into a non-target SB distal to the bifurcation. (b) Adjusting the position of the bending part of RW and the exit port of DLC together at the ostium of the non-target SB. (c) Advancing the RW and DLC simultaneously, while holding them both together. All procedures subsequent to the delivery of RW are the same as those required in conventional RWT. This technique enables us to deliver a RW through severe stenosis without the risk of either vessel injury or the occlusion of target SB. It also helps us to save time and effort in accomplishing SB access, even during the treatment of complex bifurcated lesions.

Percutaneous management of coronary bifurcation lesions: current perspective

PURPOSE OF REVIEW

Coronary artery disease affecting bifurcations poses a challenge for percutaneous intervention. Several techniques and strategies for percutaneous management of bifurcation lesions have been described in the literature with variable data available for outcomes. In this review, we provide an overview of the strategies and techniques used for percutaneous intervention of bifurcation lesions with an update of recent technical developments and clinical evidence.

RECENT FINDINGS

The coronary bifurcation lesions of both left main and other coronary segments are best treated with a provisional stenting strategy where main branch is treated with a stent placement and side branch intervention reserved for angiographically or physiologically determined hemodynamically significant residual stenosis despite application of a proximal stent optimization technique. When a provisional stent strategy is not likely to be successful due to anatomic or morphologic lesion characteristics and a large side branch or distal left main bifurcation is involved, an upfront bifurcation stenting strategy with double kissing crush technique may provide the optimum results. Coronary imaging and fractional flow determination may guide lesion specific management, facilitate device selection and improve clinical outcomes for percutaneous therapy for bifurcation lesions.

SUMMARY

Despite advances in technology and procedural techniques, percutaneous intervention of coronary bifurcation lesions remains challenging and associated with higher adverse outcomes compared to non bifurcation lesions. Among the several bifurcation strategies, a provisional stenting approach is preferred for technical simplicity and better long term outcomes. Double kissing crush technique provides superior clinical results and should be preferred when a two stent strategy is indicated. Use of coronary imaging and physiology assessment should be incorporated in the algorithm of bifurcation interventions for greater technical and clinical success.

Clinical outcomes of coronary artery bifurcation disease patients underwent Culotte two-stent technique: a single center experience

Background

Percutaneous coronary intervention for coronary artery bifurcation disease (CABD) remains challenging. In patients of CABD with situations that two-stent strategy is needed, the culotte technique is a widely used method and also as the majority at out institution. We sought to take a look of the clinical outcomes of our culotte stenting patients.

Methods

This retrospective study analyzed 238 consecutive CABD patients who underwent culotte two-stent technique at a tertiary medical center between July 2008 and November 2015.

Results

Culotte technique was used in 238 lesions in 238 patients. Of these patients, all DES were implanted for culotte two-stent technique. Most of these patients were elderly, male gender, ACS on admission and multiple vessel disease. The bifurcation lesions were mostly located at left coronary artery (51.3%), categorized as true bifurcation lesion (92%) and calculated less than 70 degree of bifurcation angle (74.4%). During a medium 3.27-year follow up, the angle of bifurcation lesion ≥70° and body mass index were positively independent predictors for target lesion failure (TLF), diabetes mellitus was an independent predictor of target vessel revascularization, and statin therapy for hyperlipidemia, hemoglobin and EF were negatively independent factors associated to total mortality. The rates of in-hospital and total mortalities were 4.2 and 17.6%.

Conclusion

In this cohort of CABD patients with most left main and left anterior descending artery lesions treated by culotte stenting, the procedural success rate was high and the intermediate clinical outcomes were acceptable. (Reviewer #1, Comment #1) Bifurcation angle (≥ 70°) is an inherently independent predictor of TLF and other two-stent strategy replaced needed to be considered in this situation.

Feasibility and safety of jailed-pressure wire technique using durable optical fiber pressure wire for intervention of coronary bifurcation lesions

OBJECTIVES

The objective was to evaluate the safety, feasibility, and accuracy of the jailed-pressure wire technique using a durable optical fiber-based pressure wire with high-pressure dilatation using a non-compliant balloon after main vessel stenting.

BACKGROUND

Fractional flow reserve (FFR) information can help interventionists determine whether they should treat a jailed-side branch (SB). However, re-crossing a pressure wire into a jailed-SB is sometimes technically difficult.

METHODS

Fifty-one consecutive lesions from 48 patients who underwent the jailed-pressure wire technique were retrospectively investigated. The primary endpoint was complication rate and secondary endpoints included success rate of FFR measurement, incidence of wire disruption, and final drift rate. The usability of FFR for percutaneous coronary intervention of coronary bifurcation lesion was also evaluated.

RESULTS

Median age of the patients was 69 years and 80.4% were men. The most frequent underlying disease was stable angina (70.6%) and 68.6% were type B2 lesions. Our main findings were: the procedure was performed successfully in all cases without any complications or wire disruption, FFR could be measured without significant final drift in 95.9% of cases, and FFR measurements helped interventionists determine whether to perform a final kissing balloon dilatation in 49.0% cases.

CONCLUSIONS

The jailed-pressure wire technique using a durable optical fiber-based pressure wire with high-pressure post-dilatation maneuver was safe, feasible, and accurate.

The EBC TWO Study (European Bifurcation Coronary TWO): A Randomized Comparison of Provisional T-Stenting Versus a Systematic 2 Stent Culotte Strategy in Large Caliber True Bifurcations

BACKGROUND

For the treatment of coronary bifurcation lesions, a provisional strategy is superior to systematic 2-stent techniques for the most bifurcation lesions. However, complex anatomies with large side branches (SBs) with significant ostial disease length are considered by expert consensus to warrant a 2-stent technique upfront. This consensus view has not been scientifically assessed.

METHODS AND RESULTS

Symptomatic patients with large caliber true bifurcation lesions (SB diameter ≥2.5 mm) and significant ostial disease length (≥5 mm) were randomized to either a provisional T-stent strategy or a dual stent culotte technique. Two hundred patients aged 64±10 years, 82% male, were randomized in 20 European centers. The clinical presentations were stable coronary disease (69%) and acute coronary syndromes (31%). SB stent diameter (2.67±0.27 mm) and length (20.30±5.89 mm) confirmed the extent of SB disease. Procedural success (provisional 97%, culotte 94%) and kissing balloon inflation (provisional 95%, culotte 98%) were high. Sixteen percent of patients in the provisional group underwent T-stenting. The primary end point (a composite of death, myocardial infarction, and target vessel revascularization at 12 months) occurred in 7.7% of the provisional T-stent group versus 10.3% of the culotte group (hazard ratio, 1.02; 95% confidence interval, 0.78-1.34; P=0.53). Procedure time, x-ray dose, and cost all favored the simpler procedure.

CONCLUSIONS

When treating complex coronary bifurcation lesions with large stenosed SBs, there is no difference between a provisional T-stent strategy and a systematic 2-stent culotte strategy in a composite end point of death, myocardial infarction, and target vessel revascularization at 12 months.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT 01560455.

A randomised comparison of Conventional versus Intentional straTegy in patients with high Risk prEdiction of Side branch OccLusion in coronary bifurcation interVEntion: rationale and design of the CIT-RESOLVE trial

INTRODUCTION

The intentional strategy (aggressive side branch (SB) protection strategy: elective two-stent strategy or jailed balloon technique) is thought to be associated with lower SB occlusion rate than conventional strategy (provisional two-stent strategy or jailed wire technique). However, most previous studies showed comparable outcomes between the two strategies, probably due to no risk classification of SB occlusion when enrolling patients. There is still no randomised trial compared the intentional and conventional strategy when treating bifurcation lesions with high risk of SB occlusion. We aim to investigate if intentional strategy is associated with significant reduction of SB occlusion rate compared with conventional strategy in high-risk patients.

METHODS AND ANALYSIS

The Conventional versus Intentional straTegy in patients with high Risk prEdiction of Side branch OccLusion in coronary bifurcation interVEntion (CIT-RESOLVE) is a prospective, randomised, single-blind, multicentre clinical trial comparing the rate of SB occlusion between the intentional strategy group and the conventional strategy group (positive control group) in a consecutive cohort of patients with high risk of side branch occlusion defined by V-RESOLVE score, which is a validated angiographic scoring system to evaluate the risk of SB occlusion in bifurcation intervention and used as one of the inclusion criteria to select patients with high SB occlusion risk (V-RESOLVE score ≥12). A total of 21 hospitals from 10 provinces in China participated in the present study. 566 patients meeting all inclusion/exclusion criteria are randomised to either intentional strategy group or conventional strategy group. The primary endpoint is SB occlusion (defined as any decrease in thrombolysis in myocardial infarction flow grade or absence of flow in SB after main vessel stenting). All patients are followed up for 12-month postdischarge.

ETHICS AND DISSEMINATION

The protocol has been approved by all local ethics committee. The ethics committee have approved the study protocol, evaluated the risk to benefit ratio, allowed operators with a minimum annual volume of 200 cases to participate in the percutaneous coronary intervention procedure and permitted them to perform both conventional and intentional strategies. Written informed consent would be acquired from all participants. The findings of the trial will be shared by the participant hospitals and disseminated through peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02644434; Pre-results.

Successful bailout stenting strategy against lethal coronary dissection involving left main bifurcation

Catheter‐induced coronary dissection involving left main bifurcation is a rare complication during cardiac catheterization but can become lethal unless it is treated appropriately. Interventional cardiologists always have to pay attention to the risk of complications related to cardiac catheterization and prepare for determining the best bailout strategy for the situation.

Tips of the dual-lumen microcatheter-facilitated reverse wire technique in percutaneous coronary interventions for markedly angulated bifurcated lesions

In practical settings of percutaneous coronary intervention (PCI), we sometimes encounter difficulty in introducing a guidewire (GW) to the markedly angulated side branch (SB), and the reverse wire technique is considered as a last resort to overcome such a situation. We analyzed 12 cases that underwent PCI with dual-lumen microcatheter-facilitated reverse wire technique between January 2013 and July 2016. We retrospectively investigated the lesion's characteristics and the details of the PCI procedures, and discussed tips about the use of this technique. The SB that exhibits both a smaller take-off angle and a larger carina angle is considered to be the most suitable candidate for this technique. The first step of this technique involves the delivery of the reverse wire system to the target bifurcation. However, most cases exhibit significant stenosis proximal to the bifurcation, which often hampers the delivery of the reverse wire system. Because the sharply curved reverse wire system is easier to pass the stenosis as compared to the roundly curved system, we recommend a sharp curve should be adopted for this technique. On the other hand, it is sure that device delivery is much easier on the GW with a round curve as compared to that with a sharp curve. Therefore, it is important to modify the details of this procedure on a case-by-case basis according to the lesion's characteristics.

Practical Usefulness of Dual Lumen Catheter-Facilitated Reverse Wire Technique for Markedly Angulated Bifurcated Lesions

OBJECTIVES

This study aimed to investigate the practical usefulness of dual lumen catheter-facilitated reverse wire technique.

BACKGROUND

We sometimes encounter difficulty in introducing a guidewire to the highly angulated side branch. In those cases, the reverse wire technique is considered as a last resort to overcome the situation.

METHODS

Between January 2013 and June 2015, we performed the reverse wire technique for guidewire crossing into an extremely angulated side branch in consecutive seven cases with true bifurcated lesions. We retrospectively evaluated patients' backgrounds, lesion characteristics, and details of the percutaneous coronary intervention (PCI) procedures.

RESULTS

Three interventional cardiologists with various levels of experience in coronary intervention performed this technique. A polymer-jacket hydrophilic-coated guidewire was used for the reverse wire system excluding in one case, and we adopted a sharp curve for the tip shape in all cases. After crossing the reverse wire into a highly angulated side branch, we usually deliver a flexible micro catheter over the guidewire for the purpose of guidewire exchange. We deployed a stent in the side branch in three cases. We successfully performed all PCI procedures without any complications and no major adverse cardiac event was observed during hospitalization.

CONCLUSIONS

We could safely and effectively perform the reverse wire technique for guidewire crossing into a markedly angulated side branch. We recommend a polymer-jacket hydrophilic-coated guidewire with a sharp curve in the tip shape for this technique. All interventional cardiologists should acquire knowledge and skills regarding this guidewire manipulation technique.

Coronary bifurcation lesions treated with simple or complex stenting: 5-year survival from patient-level pooled analysis of the Nordic Bifurcation Study and the British Bifurcation Coronary Study

AIMS

Randomized trials of coronary bifurcation stenting have shown better outcomes from a simple (provisional) strategy rather than a complex (planned two-stent) strategy in terms of short-term efficacy and safety. Here, we report the 5-year all-cause mortality based on pooled patient-level data from two large bifurcation coronary stenting trials with similar methodology: the Nordic Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study: old, new, and evolving strategies (BBC ONE).

METHODS AND RESULTS

Both multicentre randomized trials compared simple (provisional T-stenting) vs. complex (culotte, crush, and T-stenting) techniques, using drug-eluting stents. We analysed all-cause death at 5 years. Data were collected from phone follow-up, hospital records, and national mortality tracking. Follow-up was complete for 890 out of 913 patients (97%). Both Simple and Complex groups were similar in terms of patient and lesion characteristics. Five-year mortality was lower among patients who underwent a simple strategy rather than a complex strategy [17 patients (3.8%) vs. 31 patients (7.0%); P = 0.04].

CONCLUSION

For coronary bifurcation lesions, a provisional single-stent approach appears to be associated with lower long-term mortality than a systematic dual stenting technique.

A Novel Tram Stent Method in the Treatment of Coronary Bifurcation Lesions - Finite Element Study

A novel stent was designed for the treatment of coronary bifurcation lesion, and it was investigated for its performance by finite element analysis. This study was performed in search of a novel method of treatment of bifurcation lesion with provisional stenting. A bifurcation model was created with the proximal vessel of 3.2 mm diameter, and the distal vessel after the side branch (2.3 mm) was 2.7 mm. A novel stent was designed with connection links that had a profile of a tram. Laser cutting and shape setting of the stent was performed, and thereafter it was crimped and deployed over a balloon. The contact pressure, stresses on the arterial wall, stresses on the stent, the maximal principal log strain of the main artery and the side-branch were studied. The study was performed in Abaqus, Simulia. The stresses on the main branch and the distal branch were minimally increased after deployment of this novel stent. The side branch was preserved, and the stresses on the side branch were lesser; and at the confluence of bifurcation on either side of the side branch origin the von-Mises stress was marginally increased. The stresses and strain at the bifurcation were significantly lesser than the stresses and strain of the currently existing techniques used in the treatment of bifurcation lesions though the study was primarily focused only on the utility of the new technology. There is a potential for a novel Tram-stent method in the treatment of coronary bifurcation lesions.

A Novel-Modified Provisional Bifurcation Stenting Technique: Jailed Semi-Inflated Balloon Technique

OBJECTIVE

We proposed a new technique for the treatment of coronary bifurcation lesions, called jailed semi-inflated balloon technique (JSBT).

BACKGROUND

Currently, provisional approach is recommended to treat most of coronary bifurcation lesions. However, it is associated with the risk of side branch (SB) occlusion after main vessel (MV) stenting due to plaque or carina shift into the SB. The SB occlusion may cause peri-procedural myonecrosis or hemodynamic compromise. Therefore, strategies are needed to reduce the SB occlusion during provisional approach.

METHODS

Between September 2014 and April 2015, we selected 137 patients (104 male, 33 female; mean age 63.6 ± 11.7 years) with 148 distinct coronary bifurcation lesions underwent percutaneous coronary intervention using JSBT. All patients were followed with hospital visits or telephone contact up to 1 month.

RESULTS

The majority of the patients had acute coronary syndrome (64.2%) and Medina 1.1.1. bifurcation lesions (62.8%). The lesion localization was distal left main (LM) coronary artery in 28 patients. After the MV stenting, thrombolysis in myocardial infarction (TIMI) 3 flow was established in 100% of both MV and SB. There was no SB occlusion in any patient. There was no major adverse cardiac event during in-hospital stay and 1 month follow-up.

CONCLUSIONS

The JSBT technique can be successfully performed in both LM and non-LM bifurcation lesion. This technique provides high rate of procedural success, excellent SB protection during MV stenting and excellent immediate clinical outcome.

A Y-shaped bifurcation-dedicated stent for the treatment of de novo coronary bifurcation lesions: an IVUS analysis from the BRANCH trial

AIMS

The aim of this IVUS substudy was to assess the efficacy of the Y-shaped Medtronic bifurcation-dedicated stent (BDS) for the treatment of de novo coronary bifurcated lesions.

METHODS AND RESULTS

In the BRANCH trial, post-procedure IVUS was performed in 45 patients. IVUS was available in both branches in 19 lesions and only the main branch (MB) in 26 lesions. IVUS analysis included four distinct locations: proximal MB, bifurcation site, distal MB, and side branch (SB). Lumen symmetry was calculated as minimum/maximum lumen diameters. The quantity of isolated stent struts across the SB ostium was used to assess inadequate strut apposition to the carina resulting in partial jailing of the SB orifice. A minimum stent area (MSA) <4 mm2 was found in 0% of proximal and distal MB, and in 15.4% of SB. In SB, MSA was located mainly at mid or distal segments (84.6%), rather than at the SB ostium. Eccentric stent expansion and edge dissection were seen primarily at proximal MB. Isolated struts were seen in only 20.9% of SB ostia with a minimum length of 0.7±0.4 mm.

CONCLUSIONS

Implantation of BDS resulted in adequate stent dimensions and strut apposition at the carina and SB ostium. ClinicalTrials.gov Identifier: NCT00607321.

Clinical outcome after crush versus culotte stenting of coronary artery bifurcation lesions: the Nordic Stent Technique Study 36-month follow-up results

OBJECTIVES

The aim of the study was to compare long-term follow-up results of crush versus culotte stent techniques in coronary bifurcation lesions.

BACKGROUND

The randomized Nordic Stent Technique Study showed similar 6-month clinical and 8-month angiographic results with the crush and culotte stent techniques of de novo coronary artery bifurcation lesions using sirolimus-eluting stents. Here, we report the 36-month efficacy and safety of the Nordic Stent Technique Study.

METHODS

A total of 424 patients with a bifurcation lesion were randomized to stenting of both main vessel and side branch with the crush or the culotte technique and followed for 36 months. Major adverse cardiac events-the composite of cardiac death, myocardial infarction, stent thrombosis, or target vessel revascularization-were the primary endpoint.

RESULTS

Follow-up was complete for all patients. At 36 months, the rates of the primary endpoint were 20.6% versus 16.7% (p = 0.32), index lesion restenosis 11.5% versus 6.5% (p = 0.09), and definite stent thrombosis 1.4% versus 4.7% (p = 0.09) in the crush and the culotte groups, respectively.

CONCLUSIONS

At 36-month follow-up, the clinical outcomes were similar for patients with coronary bifurcation lesions treated with the culotte or the crush stent technique. (Nordic Bifurcation Study. How to Use Drug Eluting Stents [DES] in Bifurcation Lesions? NCT00376571).

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.

New strategies in the treatment of coronary bifurcations

Despite major improvements in stent technology (i.e., drug-eluting stents, DES), treatment of coronary bifurcations is an ever occurring problem of the interventional cardiology. While stenting the main branch with provisional side branch stenting seems to be the prevailing approach, in the era of DES various two-stent techniques emerged (crush) or were re-introduced (V or simultaneous kissing stents, crush, T, culottes, etc.) to allow stenting in the side branch when needed. New techniques in imaging like optical coherence tomography help in better understanding bifurcation anatomy and, thus, have the potential to help us better treat this challenging subset of lesions. In addition, new dedicated bifurcation stents have been proposed in an attempt to overcome limitations associated with current approaches, and they showed promising results in early studies; however, the safety and the efficacy of these devices remain to be seen in the ongoing and upcoming trials. This review focuses on the current approaches and the development of new techniques employed for the treatment of bifurcation disease.

Delayed Coverage in Malapposed and Side-Branch Struts With Respect to Well-Apposed Struts in Drug-Eluting Stents

Background—

Pathology studies on fatal cases of very late stent thrombosis have described incomplete neointimal coverage as common substrate, in some cases appearing at side-branch struts. Intravascular ultrasound studies have described the association between incomplete stent apposition (ISA) and stent thrombosis, but the mechanism explaining this association remains unclear. Whether the neointimal coverage of nonapposed side-branch and ISA struts is delayed with respect to well-apposed struts is unknown.

Methods and Results—

Optical coherence tomography studies from 178 stents implanted in 99 patients from 2 randomized trials were analyzed at 9 to 13 months of follow-up. The sample included 38 sirolimus-eluting, 33 biolimus-eluting, 57 everolimus-eluting, and 50 zotarolimus-eluting stents. Optical coherence tomography coverage of nonapposed side-branch and ISA struts was compared with well-apposed struts of the same stent by statistical pooled analysis with a random-effects model. A total of 34 120 struts were analyzed. The risk ratio of delayed coverage was 9.00 (95% confidence interval, 6.58 to 12.32) for nonapposed side-branch versus well-apposed struts, 9.10 (95% confidence interval, 7.34 to 11.28) for ISA versus well-apposed struts, and 1.73 (95% confidence interval, 1.34 to 2.23) for ISA versus nonapposed side-branch struts. Heterogeneity of the effect was observed in the comparison of ISA versus well-apposed struts (H=1.27; I 2 =38.40) but not in the other comparisons.

Conclusions—

Coverage of ISA and nonapposed side-branch struts is delayed with respect to well-apposed struts in drug-eluting stents, as assessed by optical coherence tomography.

Clinical Trial Registration—

http://www.clinicaltrials.gov . Unique identifier: NCT00389220, NCT00617084.

The outcome of bifurcation lesion stenting using a biolimus-eluting stent with a bio-degradable polymer compared to a sirolimus-eluting stent with a durable polymer

AIMS

This study investigated the differences in clinical outcomes between patients with bifurcation lesions (BL) treated with a biolimus-eluting stent (BES) with a biodegradable polymer, and a sirolimus-eluting stent (SES) with a durable polymer.

METHODS AND RESULTS

The clinical outcomes were assessed in the 497 patients (BES 258, SES 239) enrolled in the multicentre, randomised LEADERS trial who underwent treatment of ≥1 BL (total=534 BL). At 12-months follow-up there was no significant difference in the primary endpoint of MACE, a composite of cardiac death, myocardial infarction and clinically indicated target vessel revascularisation (BES 12.8% vs. SES 16.3%, p=0.31). Patients treated with BES had comparable rates of cardiac death (BES 2.7% vs. SES 2.9%, p=1.00), numerically higher rates of myocardial infarction (BES 8.9% vs. SES 5.4%, p=0.17), and significantly lower rates of clinically indicated target vessel revascularisation (4.3% vs. 11.3%, p=0.004) when compared to those treated with SES. The rate of stent thrombosis at 12-months was 4.3% and 3.8% for BES and SES, respectively (p=0.82).

CONCLUSIONS

In the treatment of BL the use of BES lead to superior efficacy and comparable safety compared to SES.

Six-month clinical follow-up of the Tryton side branch stent for the treatment of bifurcation lesions: a two center registry analysis

BACKGROUND

Treatment of bifurcation lesions with the Tryton Sidebranch stent has been shown to be feasible with an acceptable clinical outcome and low side branch late loss in the first in man trial.

OBJECTIVE

To report acute procedural and six month clinical follow-up after the use of the Tryton Sidebranch stent in an "all comer" registry.

METHODS

The first 100 coronary bifurcation lesions assigned for treatment with the Tryton stent were included in a prospective registry. Procedural and angiographic success rates were determined from patient charts and pre- and postprocedural quantitative coronary angiography.

RESULTS

Totally, 96 patients with 100 lesions were included in the study. Seventy-two percent presented with stable angina, 25% with unstable angina/NSTEMI, and 3% STEMI. The bifurcation was located in the left main in 8%. Two lesions were chronic total occlusions. Sixty-nine percent were true bifurcation lesions. One failure of stent delivery occurred. Acute gain in SB was 0.76 ± 0.64 mm and three patients had residual stenosis of >30%. Angiographic success rate was 95%; procedural success rate reached 94%. Peri-procedural MI occurred in two and there was one cardiac death during hospitalization. At a median six months follow-up, TLR rate was 4%, MI 3%, and cardiac death 1%. The percentage MACE-free survival at six months was 94%. No cases of definite stent thrombosis occurred.

CONCLUSIONS

In a real world the use of the Tryton Sidebranch stent is associated with good procedural safety and angiographic success rate and acceptable outcome at six months of follow-up.

Simple or Complex Stenting for Bifurcation Coronary Lesions

Background—

Controversy persists regarding the correct strategy for bifurcation lesions. Therefore, we combined the patient-level data from 2 large trials with similar methodology: the NORDIC Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study (BBC ONE).

Methods and Results—

Both randomized trials compared simple (provisional T-stenting) versus complex techniques, using drug-eluting stents. In the simple group (n=457), 129 patients had final kissing balloon dilatation in addition to main vessel stenting, and 16 had T-stenting. In the complex group (n=456), 272 underwent crush, 118 culotte, and 59 T-stenting techniques. A composite end point at 9 months of all-cause death, myocardial infarction, and target vessel revascularization occurred in 10.1% of the simple versus 17.3% of the complex group (hazard ratio 1.84 [95% confidence interval 1.28 to 2.66], P =0.001). Procedure duration, contrast, and x-ray dose favored the simple approach. Subgroup analysis revealed similar composite end point results for true bifurcations (n=657, simple 9.2% versus complex 17.3%; hazard ratio 1.90 [95% confidence interval 1.22 to 2.94], P =0.004), wide-angled bifurcations >60 to 70° (n=217, simple 9.6% versus complex 15.7%; hazard ratio 1.67 [ 95% confidence interval 0.78 to 3.62], P =0.186), large (≥2.75 mm) diameter side branches (n=281, simple 10.4% versus complex 20.7%; hazard ratio 2.42 [ 95% confidence interval 1.22 to 4.80], P =0.011), longer length (>5 mm) ostial side branch lesions (n=464, simple 12.1% versus complex 19.1%; hazard ratio 1.71 [95% confidence interval 1.05 to 2.77], P =0.029), or equivalent sized vessels (side branch <0.25 mm smaller than main vessel) (n=108, simple 12.0% versus complex 15.5%; hazard ratio 1.35 [95% confidence interval 0.48 to 3.70], P =0.57).

Conclusions—

For bifurcation lesions, a provisional single-stent approach is superior to systematic dual stenting techniques in terms of safety and efficacy. A complex approach does not appear to be beneficial in more anatomically complicated lesions.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT 00376571 and NCT 00351260.

Coronary stents: looking forward

Despite all the benefits of drug-eluting stents (DES), concerns have been raised over their long-term safety, with particular reference to stent thrombosis. In an effort to address these concerns, newer stents have been developed that include: DES with biodegradable polymers, DES that are polymer free, stents with novel coatings, and completely biodegradable stents. Many of these stents are currently undergoing pre-clinical and clinical trials; however, early results seem promising. This paper reviews the current status of this new technology, together with other new coronary devices such as bifurcation stents and drug-eluting balloons, as efforts continue to design the ideal coronary stent.

Real-world outcome of coronary bifurcation lesions in the drug-eluting stent era: results from the 4,314-patient Italian Society of Invasive Cardiology (SICI-GISE) Italian Multicenter Registry on Bifurcations (I-BIGIS)

BACKGROUND

Drug-eluting stents (DESs) introduction has somewhat renewed the issues of strategy and stenting technique for treatment of bifurcation lesions. In particular, concerns remain on extensive use of DESs, especially in the side branch, and on time of dual antiplatelet therapy (DAT) discontinuation, reflecting lack of pertinent long-term data. This study aimed to evaluate clinical safety and efficacy of different strategies for bifurcations treatment in a large observational real-world registry.

METHODS

A multicenter, retrospective Italian study of consecutive patients undergoing bifurcation percutaneous coronary intervention between January 2002 and December 2006 was performed. The primary end point was the long-term rate of major adverse cardiac events (MACEs). The role of DAT length on outcome was also analyzed.

RESULTS

A total of 4,314 patients (4,487 lesions) were enrolled at 22 independent centers. In-hospital procedural success rate was 98.7%. After median follow-up of 24 months, MACEs occurred in 17.7%, with cardiac death in 3.4%, myocardial infarction in 4.0%, target lesion revascularization in 13.2%, and stent thrombosis in 2.9%. Extensive multivariable analysis showed that MACEs were independently predicted by age, diabetes, renal failure, systolic dysfunction, multivessel disease, myocardial infarction at admission, restenotic lesion, bare-metal stent implantation, complex stenting strategy, and short duration of DAT.

CONCLUSIONS

This large study based on current clinical practice in an unselected patient population presenting with bifurcation disease and submitted to percutaneous coronary intervention demonstrated favorable long-term clinical results in this challenging patient setting, especially when DESs, simple stenting strategy, and DAT for at least 6 months are used.

Simple versus complex approaches to treating coronary bifurcation lesions: direct assessment of stent strut apposition by optical coherence tomography

INTRODUCTION AND OBJECTIVES

Stenting of coronary bifurcation lesions carries an increased risk of stent deformation and malapposition. Anatomical and pathological observations indicate that the high stent thrombosis rate in bifurcations is due to malapposition of stent struts.

METHODS

Strut apposition was assessed with optical coherence tomography (OCT) in bifurcation lesions treated either using the simple technique of stent implantation in the main vessel only or a complex technique (i.e. Culotte's). A strut was regarded as malapposed if the gap between its endoluminal surface and the vessel wall was greater than its thickness plus an OCT resolution error margin of 15 microm.

RESULTS

Simple and complex (i.e. Culotte's) approaches were used in 17 and 14 patients, respectively. Strut malapposition was significantly more frequent for the half of the bifurcation on same side as the vessel side branch (median, 46.1%; interquartile range [IQR], 35.3-62.5%) than for the half opposite the side branch (9.1%; IQR, 2.2-21.6%), the distal segment (7.5%; IQR, 2.3-20.2%) or the proximal segment (12.6%; IQR, 7.8-23.1%; P< .0001); the gap between strut and vessel wall in malapposed struts was significantly greater in the first segment than the others: 98 microm (IQR, 37-297 microm) vs. 31 microm (IQR, 13-74 microm), 49 microm (IQR, 20-100 microm) and 38 microm (IQR, 17-90 microm), respectively (P< .0001). Using the complex technique had no effect on the prevalence of strut malapposition in the four segments relative to the simple technique (P=.31) but was associated with a smaller gap in the proximal segment (47 microm vs. 60 microm; P=.0008).

CONCLUSIONS

In coronary bifurcation lesions, strut malapposition occurred most frequently and was most significant close to the side branch ostium. The use of Culotte's technique did not significantly increase the prevalence of strut malapposition compared with a simple technique.

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.

Long-term outcome of bifurcation stenting with drug-eluting stents

There are little long-term clinical data regarding the safety and efficacy of using 2 drug-eluting stents (DESs) to treat coronary bifurcation lesions. We obtained clinical follow-up for 124 consecutive patients who underwent bifurcation stenting with 2 DESs. Major adverse cardiac events (MACEs) were defined as cardiac death, acute myocardial infarction (AMI), and target vessel revascularization (TVR). Sixty-four (52%) patients underwent ''crush,'' 42 (34%) patients underwent T stent, and 18 (14%) patients underwent kissing stent. Major adverse cardiac events were observed in 19 patients (17%) at 1 year: 6 (5%) AMI, 13 (12%) TVR, and no deaths, and 29 patients (26 %) at a mean follow-up of 22 months: 7 (6%) AMI, 21 (19%) TVR, and 1 (1%) death. No statistically significant risk factors for long-term MACEs were identified. It appears that treating bifurcation lesions with 2 DESs when necessary can be performed with an acceptable MACE rate.

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 degrees , 50 degrees , 70 degrees , and 90 degrees . 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 cm(3)) 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.

Double versus single stenting for coronary bifurcation lesions: a meta-analysis

BACKGROUND

Several trials have addressed whether bifurcation lesions require stenting of both the main vessel and side branch, but uncertainty remains on the benefits of such double versus single stenting of the main vessel only.

METHODS AND RESULTS

We have conducted a meta-analysis of randomized trials including patients with coronary bifurcation lesions who were randomly selected to undergo percutaneous coronary intervention by either double or single stenting. Six studies (n=1642 patients) were eligible. There was increased risk of myocardial infarction with double stenting (risk ratio, 1.78; P=0.001 by fixed effects; risk ratio, 1.49 with Bayesian meta-analysis). The summary point estimate suggested also an increased risk of stent thrombosis with double stenting, but the difference was not nominally significant given the sparse data (risk ratio, 1.85; P=0.19). No obvious difference was seen for death (risk ratio, 0.81; P=0.66) and target lesion revascularization (risk ratio, 1.09; P=0.67).

CONCLUSIONS

Stenting of both the main vessel and side branch in bifurcation lesions may increase myocardial infarction and stent thrombosis risk compared with stenting of the main vessel only.