Treatment of bifurcation lesions with two stents: one year angiographic and clinical follow up of crush versus T stenting

Nano-crush technique in narrow angle (<70˚) bifurcation - bench test, computed tomographic reconstruction, fluid dynamics, and clinical outcomes

BACKGROUND

Bifurcation stenting techniques are still refining and under testing. Nano-crush is a novel technique which allow minimum protrusion of side branch struts at the ostium. To demonstrate the efficacy of Nano-crush technique in narrow-angle bifurcation (<70˚) using bench test model, 3D reconstruction of the stent structure, computational fluid dynamics study and a clinical follow-up.

METHODS

This was a retrospective observational single-centre study which included 40 patients who underwent angioplasty using Nano-crush technique for de-novo complex coronary bifurcation lesions with narrow bifurcation angle(<70˚) between April-2016 to March-2019. The in-vitro bench test and computational fluid dynamics analysis were performed using a bifurcation model designed. The clinical primary endpoint was major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction, and target lesion revascularization (TLR) at one-year angiographic follow-up.

RESULTS

The reconstructed results of in-vitro bench test showed minimum length of stent struts moving away from the rounded side branch ostium. The mean age of patients was 62.8 ± 7.98 years (32 male) and presented 100% procedural success. The mean bifurcation angle was 47.3˚ ± 9.2˚. The MACE was reported in 4 (10%) patients which included 1 (2.5%) death and 3 (7.5%) TLR at the mean follow-up of 35.54 ± 12.31 months. No significant correlation between occurrence of MACE and gender, age, comorbidities and bifurcation angle was reported.

CONCLUSIONS

The Nano-crush technique demonstrated least metal load around carina and abnormal flow dynamics in narrow angle (<70˚) bifurcation lesions and also reported favorable long-term clinical outcomes.

A novel &ldquo;nano-crush&rdquo; technique for the management of coronary bifurcation lesions: in vitro bench test analysis and preliminary report on real-world clinical evaluation in patients with one-year angiographic follow-up

Aims

Although provisional stenting with a single drug-eluting stent has proven clinical efficacy in the treatment of bifurcation stenosis, some patients may require two stents. We propose a novel technique, called "nano-crush", which is easy to perform and can be used in all bifurcation angles.

Methods and results

The feasibility of the nano-crush technique was confirmed in an in vitro bench test and intravascular ultrasound (IVUS) study. Subsequently, 42 patients with de novo coronary bifurcation stenosis were treated by this novel procedure using drug-eluting stents at our centre between January 2008 and December 2015. We experienced procedural success in all (100%) patients without any complications. The primary efficacy endpoint of the one-year incidence of major adverse cardiac events (MACE) was noted in three (7.14%) patients, comprising one case of cardiac death at nine months post procedure and two cases of repeat revascularisation due to in-stent restenosis. There were no cases of periprocedural myocardial infarction or stent thrombosis. Angiographic follow-up at one year indicated intact stent patency in the remaining patients.

Conclusions

Initial experience with the nano-crush technique demonstrates that it can be performed easily without any procedural complications. Further, the angiographic and clinical follow-up indicates that the nano-crush technique is associated with acceptable clinical outcomes in a real-world scenario.

Treatment strategies for coronary bifurcation lesions made easy in the current era by introduction of the BIFURCAID app

Coronary bifurcation lesions account for 15-20% of all percutaneous coronary interventions. Percutaneous revascularization of these lesions is technically challenging and results in lower success rates than nonbifurcation lesions. There are unique procedural considerations and techniques that are employed in the percutaneous revascularization of these lesions. Our objective is to define the procedural complexities of treating coronary bifurcation lesions and describe the leading provisional and dedicated two stent techniques used to optimize procedural and clinical results, as described in the BIFURCAID app.

Final kissing balloon inflation for coronary bifurcation lesions treated with single-stent technique : A meta-analysis

BACKGROUND

The efficacy of final kissing balloon (FKB) inflation in one-stent techniques for bifurcation lesions is controversial. The goal of the present study was to investigate the impact of FKB on long-term clinical outcomes in one-stent strategies.

METHODS

A literature search of the PubMed, Embase, and Cochrane Library databases was undertaken through August 2017. The primary outcome was major adverse cardiac events (MACE), defined as the composite of cardiac death, myocardial infarction, and target lesion revascularization. Overall hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using the random-effects model.

RESULTS

Ten studies comprising 7364 patients treated with a one-stent technique were included in the analysis. Overall, FKB did not demonstrate a significant reduction in MACE compared with non-FKB in both randomized trials (HR: 1.13; 95% CI: 0.65-1.98) and observational studies (HR: 0.86; 95% CI: 0.61-1.20). The risk of cardiac death (HR: 0.89; 95% CI: 0.53-1.49), myocardial infarction (HR: 0.76; 95% CI: 0.53-1.09), and target lesion revascularization (HR: 0.96; 95% CI: 0.74-1.23) was also similar in both groups.

CONCLUSION

FKB may not be mandatory and a selective FKB strategy might be more justified in one-stent techniques for bifurcation lesions.

Impact of very high pressure stent deployment on angiographic and long-term clinical outcomes in true coronary bifurcation lesions treated by the mini-crush stent technique: A single center experience

Background

Percutaneous coronary intervention (PCI) for bifurcation lesions (BL) using 2 stents technique is known to be associated with high rates of procedural failure especially on the side branch (SB) mainly due to stent incomplete apposition. Stent deployment at very high pressure (SDHP) may lead to better stent expansion and apposition. However, SDHP may also be at the origin of deeper wall injury resulting into major cardiac adverse events. No data are available on evaluation of SDHP in BL treated by a mini-crush stent technique.

Methods

One hundred and thirteen consecutive patients underwent PCI for BL (Medina 1, 1, 1) using a mini-crush stent technique with SDHP defined as ≥20 atm. An angiographic follow-up was performed at 6 month and clinical follow-up was obtained at a median of 3 years.

Results

Stent deployment mean pressures were 20 ± 1.4 atm (range 20–25) in the main vessel (MV) and 20 ± 1.5 atm (range 20–25) in SB. Simultaneous final kissing balloon was used in 92% of cases. PCI was successful in 100%. Angiographic follow-up was obtained in 83% of patients. Restenosis rate was 13% (12% restenosis in the SB) with only one case (0.8%) of SB probable thrombosis. Another case of late stent thrombosis occurred at a 3 years clinical follow-up.

Conclusion

Compared with previously published studies in which stents were deployed at lower pressure, SDHP does not increase the restenosis rate in BL using mini-crush stent technique but seems to reduce the rate of stent thrombosis.

Randomized Comparisons Between Different Stenting Approaches for Bifurcation Coronary Lesions With or Without Side Branch Stenosis

OBJECTIVES

This study sought to evaluate the optimal percutaneous coronary intervention techniques using drug-eluting stents for bifurcation coronary lesions.

BACKGROUND

The optimal bifurcation stenting technique needs to be evaluated.

METHODS

The trial included 2 randomization studies separated by the presence of side branch (SB) stenosis for patients having non-left main bifurcation lesions. For 306 patients without SB stenosis, the routine final kissing balloon or leave-alone approaches were compared. Another randomization study compared the crush or single-stent approaches for 419 patients with SB stenosis.

RESULTS

Between the routine final kissing balloon and leave-alone groups for nondiseased SB lesions, angiographic restenosis occurred in 17.9% versus 9.3% (p=0.064), comprising 15.1% versus 3.7% for the main branch (p=0.004) and 2.8% versus 5.6% for the SB (p=0.50) from 214 patients (69.9%) receiving 8-month angiographic follow-up. Incidence of major adverse cardiac events including death, myocardial infarction, or target vessel revascularization over 1 year was 14.0% versus 11.6% between the routine final kissing balloon and leave-alone groups (p=0.57). In another randomization study for diseased SB lesions, 28.2% in the single-stent group received SB stents. From 300 patients (71.6%) receiving angiographic follow-up, between the crush and single-stent groups, angiographic restenosis rate was 8.4% versus 11.0% (p=0.44), comprising 5.2% versus 4.8% for the main branch (p=0.90) and 3.9% versus 8.3% for the SB (p=0.12). One-year major adverse cardiac events rate between the crush and single-stent groups was 17.9% versus 18.5% (p=0.84).

CONCLUSIONS

Angiographic and clinical outcomes were excellent after percutaneous coronary intervention using drug-eluting stents with any stent technique for non-left main bifurcation lesions once the procedure was performed successfully.

Optimal kissing balloon inflation after single-stent deployment in a coronary bifurcation model

AIMS

To define the optimal kissing balloon inflation (KBI) after single-stent deployment in a coronary bifurcation model.

METHODS AND RESULTS

We deployed stents in main vessels (MV) followed by KBI in various conditions and compared the stent configurations. A) KBI at the operator's discretion vs. under the guidelines of minimal balloon overlapping (MBO). Various stent configurations were observed after the former option, whereas similar maximal dilation points were observed under the MBO guidelines. B) Long balloon overlapping (LBO) vs. MBO with proximal MV dilated by a large balloon. The proximal MV was dilated to an ideal round shape with MBO versus an oval shape with LBO. C) Two-link vs. 3-link stents. Although the 2-link stent was advantageous to open the side branch, it incurred a risk of overdilatation of the proximal struts, whereas the 3-link stent preserved its structure. Computed simulations of coronary flow were analysed in the following left main coronary models: circle with a diameter of 4 and 5.5 mm, ellipse with longitudinal direction and tilt position. They revealed that the overdilated side was exposed to low shear stress regardless of its shape.

CONCLUSIONS

Optimal KBI can be achieved with MBO and proximal dilatation by an optimally sized balloon.

Usefulness of Corsair microcatheter to cross stent struts in bifurcation lesions

Side branch compromise after stenting in bifurcation lesions is a matter of concern. It may happen that even low-profile balloon catheters do not cross stent struts after rewiring. The Corsair catheter is a hybrid catheter that has features of a microcatheter and a support catheter. The present study evaluated usefulness of the Corsair catheter to facilitate advancing a low-profile balloon catheter through stent struts in bifurcation lesions. After rewiring, low-profile balloon catheters failed to cross stent struts of 29 bifurcation lesions. The Corsair microcatheter successfully crossed stent struts in all lesions except one (97 %) where a stent was implanted to treat in-stent restenosis (stent-in-stent). Low-profile balloon catheters were able to advance into the side branch of all bifurcation lesions where the Corsair microcatheter crossed stent struts. In conclusion, the Corsair microcatheter may be utilized if low-profile balloon catheters are unable to cross stent struts in bifurcation lesions.

Incidence, correlates, and significance of abnormal cardiac enzyme rises in patients treated with surgical or percutaneous based revascularisation: a substudy from the Synergy between Percutaneous Coronary Interventions with Taxus and Cardiac Surgery (SYNTAX) Trial

AIMS

The aim of the present investigation was to determine the long-term prognostic association of post-procedural cardiac enzyme elevation within the randomised Synergy between Percutaneous Coronary Intervention (PCI) with TAXUS and Cardiac Surgery (SYNTAX) Trial.

METHODS

1800 patients with unprotected left main or de novo three-vessel coronary artery disease were randomised to undergo coronary artery bypass graft (CABG) surgery or PCI. Per protocol patients underwent post-procedural blood sampling with creatine kinase (CK), and the cardiac specific MB iso-enzyme (CK-MB) only if the preceding CK ratio was ≥ 2 × the upper limit of normal (ULN). An independent chemistry laboratory evaluated all collected blood samples.

RESULTS

Post-procedural CK sampling was available in 1629 of 1800 patients (90.5%). As per protocol, CK-MB analyses were undertaken in 474 of 491 patients (96.5%) in the CABG arm, and 53 of 61 patients (86.9%) in the PCI arm. Within the CABG arm, despite the limitations of incomplete data, a post-procedural CK-MB ratio <3/≥3 ULN separated 4-year mortality into low- and high-risk groups (2.3% vs. 9.5%, p=0.03). Additionally, in the CABG arm, a post-procedural CK-MB ratio ≥3 ULN was associated with an increased frequency of a high SYNTAX Score (≥33) tertile (high [≥33] SYNTAX Score: 39.5%, intermediate [23-32] SYNTAX Score 31.0%, low [≤22] SYNTAX Score 29.5%, p=0.02). Within the PCI arm, a post-procedural CK ratio of <2 or ≥2 ULN separated 4-year mortality into low- and high-risk groups (10.8% vs. 23.3%, p=0.001). Notably, there was an early (within 6 months) and late (after 2 years) peak in mortality in patients with a post-PCI CK ratio of ≥2 ULN. Lack of pre-procedural thienopyridine, carotid artery disease, type 1 diabetes, and presence of coronary bifurcations were independent correlates of a CK ratio ≥2 ULN post-PCI.

CONCLUSION

Cardiac enzyme elevations post-CABG or post-PCI are associated with an adverse long-term mortality; the causes of which are multifactorial.

Magnetic navigation system assisted stenting of coronary bifurcation lesions

AIMS

Magnetic guidewire assisted percutaneous coronary interventions (MPCI) could have certain advantages in coronary bifurcation lesions. We aimed to report the angiographic characteristics of the bifurcation lesions, as well as the procedural and clinical outcomes of the MPCI patients.

METHODS AND RESULTS

The lesion characteristics and the treatment effect were assessed by performing diagnostic and quantitative coronary angiography with dedicated bifurcation software. A total of 76 patients (age 65 years, 78% male) were assigned to undergo MPCI, in which two-thirds of the lesions were located in LAD/D1. Fifty-seven out of 78 lesions (73%) had a diseased side branch and complex stenting techniques were used in the majority of the lesions (64%). All 59/78 (76%) fenestration attempts were successfully performed and only 13 dedicated bifurcation stents were implanted. The average acute gain in minimal luminal diameter was 1.08±0.81 mm, 0.80±0.70 mm and 0.59±0.56 mm for the proximal, distal and side branch, respectively. The procedural success was 69% with a procedure time of 107±43 minutes, fluoroscopy time of 34±24 minutes and contrast use of 338±136 ml. At a mean of 1.8-years follow-up, 15 patients (20%) had a cardiac event.

CONCLUSIONS

MPCI is associated with good angiographic, fenestration and procedural success rates in the treatment of coronary bifurcation lesions.

A simple method preventing tangling of the guidewires during percutaneous coronary intervention for bifurcation lesions

The aim was to examine the efficacy of the simple technique that reduces tangling of the guidewires by utilizing wet gauze during percutaneous coronary intervention with multiple guidewires. We defined "Critical tangle of the guidewires" as occurring when it became impossible to insert balloon catheters into the bifurcation lesion due to tangling of the guidewires without withdrawing and reinserting one of the guidewires. We compared the rate of the critical tangle of the guidewires between the group taking no special tangle precaution ("NP Group"), and the group taking the tangle precaution with the wet gauze ("Gauze Group"). Eighty-four patients were enrolled in the study and randomly assigned to either NP Group (n = 43) or Gauze Group (n = 41). The kissing balloon technique success was 42/43 (97.7%) versus 40/41 (97.6%), in NP Group and Gauze Group, respectively. The rate of critical tangle of the guidewires was significantly lower in Gauze Group (27.9 vs. 7.3%, p = 0.014). The manipulation of several guidewires utilizing gauze method will be a useful technique for reducing tangle of the guidewires during the procedure of kissing balloon technique.

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.

Long-term clinical results and predictors of adverse outcomes after drug-eluting stent implantation for bifurcation lesions in a real-world practice: the COBIS (Coronary Bifurcation Stenting) registry

BACKGROUND

Limited data exists regarding long-term clinical results and predictors of adverse outcomes after drug-eluting stents (DES) implantation for coronary bifurcation lesions in a real-world practice.

METHODS AND RESULTS

A total of 1,691 non-left main bifurcation lesions with side branches ≥2.0mm in 1,668 patients undergoing DES implantation between January 2004 and June 2006 from 16 centers in Korea were evaluated. True bifurcation was found in 69.2% of lesions and 82.7% of lesions were treated with 1-stent technique. During follow-up (median 22 months), cardiac death occurred in 0.9%, myocardial infarction (MI) in 1.2%, target lesion revascularization (TLR) in 4.7% and stent thrombosis in 0.7% of patients. There was no significant difference in major adverse cardiac events (MACE: composite of cardiac death, MI and TLR) between the 1-stent and the 2-stent groups (6.1% vs 7.5%, P=0.36). Stent length in the main vessel (hazard ratio (HR) 1.02, 95% confidence interval (CI) 1.001-1.03, P=0.03), paclitaxel-eluting stent (HR 1.98, 95%CI 1.34-2.92, P=0.001) and kissing ballooning (HR 2.01, 95%CI 1.29-3.13, P=0.002) were independent predictors of MACE. Kissing ballooning increased the risk of MACE especially in the 1-stent group, but not in the 2-stent group.

CONCLUSIONS

In this large real-world registry, overall outcomes after DES implantation in bifurcation lesions were favorable and similar between the 1-stent and 2-stent groups.

Crush stenting with drug-eluting stents: relevance of coronary bifurcation lesion location on angiographic and clinical outcomes

BACKGROUND

Data on the relevance of the location of coronary bifurcation lesions treated by crush stenting with outcomes were limited.

HYPOTHESIS

We hypothesized that the location of the bifurcation lesion correlated with clinical outcome.

METHOD

A total of 212 patients with 230 true bifurcation lesions treated by crush stenting with drug-eluting stents (DES) were assessed prospectively. Surveillance quantitative angiographies were indexed at 8 months after procedure. Primary endpoint was major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, and target lesion revascularization (TLR).

RESULTS

Patients in the distal right coronary artery (RCAd) group were characterized by higher proportions of prior myocardial infarction and very tortuous lesions. However, lesions in the RCAd group, compared to those of other groups, had the lowest late lumen loss, with resultant lowest incidence of MACE at a mean follow-up of 268±35 days. Independent predictors of MACE included unsatisfied kissing (KUS; hazard ratio [HR]: 12.14, 95% confidence interval [CI]: 4.01-12.10, P = .001) and non-RCA lesion (HR: 20.69, 95% CI: 5.05-22.38, P = .001), while those of TLR were KUS (HR: 10.21, 95% CI: 0.01-0.34, P = .002), bifurcation angle (HR: 4.728, 95% CI: 2.541-4.109, P = .001), and non-RCA lesion (HR: 16.05, 95%CI: 1.01-4.83, P = .001).

CONCLUSIONS

Classical crush stenting with drug-eluting stents is associated with significantly better outcomes in RCAd. Quality of kissing inflation is mandatory to improve outcome.

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.

Off-label use of drug-eluting versus bare metal stents: a lesion-specific systematic review of long-term outcomes

OBJECTIVE

The purpose of this systematic review was to evaluate differences in lesion-specific outcomes with the "off-label" use of drug-eluting stents (DES) versus bare metal stents (BMS).

METHODS

MEDLINE, PubMed, the Cochrane databases, and other Web were searched for studies evaluating off-label use of DES and BMS with the same characteristics. Of 1,258 abstracts or manuscripts reviewed, 112 studies were included (total N = 23,438). Studies were excluded if patients received both types of stent or no stent; lesion type was unknown; lesion-specific outcomes for ≥6 months were unavailable; or <25 patients were enrolled.

RESULTS

Overall mortality at 6-12 months was approximately 3% for BMS and DES for off-label use. Increase in mortality was greater from 6-12 months to 2 years with BMS than with DES (3.3%-9.1%; 2.8%-4.1%); however, rates were similar at 3 years (BMS: 18.8%; DES:15.3%). Myocardial Infarction rates were similar for both types at 6-12 months (BMS: 6.5%; DES: 6.0%). Overall rates of stent thrombosis were 1.8% and 1.7% for BMS and DES, respectively. Similar or slightly lower rates of stent thrombosis were seen for most lesion types, except higher rates for small vessels for BMS (5.2%) and true bifurcation for DES (3.3%). Rates of target lesion revascularization (TLR) were 7.5% for BMS and 19.6% for DES at 6-12 months. At 2-years TLR remained lower than DES. When the combined group was compared to registry data alone, similar values were seen.

CONCLUSIONS

Rates of mortality, myocardial infarction (MI), and stent thrombosis were similar in patients receiving BMS or DES, while TLR rates were lower in DES patients.

Stent thrombosis following 2 drug-eluting stent implantations for coronary bifurcation lesion: a single-center analysis

BACKGROUND

The incidence of stent thrombosis (ST) following 2 drug-eluting stent (DES) implantations for coronary bifurcation lesions needs to be identified.

METHODS

From April 2004 to April 2009, 705 consecutive patients with true bifurcation lesions who underwent a double stenting procedure with DES at the Fu Wai Hospital were analyzed.

RESULTS

Six (0.85%) patients had a definite ST, all of them had an early (4 acute and 2 subacute) definite ST. Probable ST occurred in 4 patients; in all of these cases, the event occurred early and was adjudicated because of the occurrence of sudden death within 30 days of the procedure. Therefore, a total of 10/705 (1.42%) patients had a definite or probable ST. Possible stent thrombosis was adjudicated only in 1 patient 371 days after the initial PCI in whom the cause of death was unexplained. Compared to the patients without definite and probable ST, patients with definite and probable ST were older, had more unstable angina, lower LVEF, and more left main bifurcation lesions (63.2 +/- 8.9 vs. 56.8 +/- 10.9 yrs; P = 0.049, 100% vs. 64.7%; P = 0.018, 50.6 +/- 9.9 vs. 60.3 +/- 12.4%; P = 0.019 and 70.0% vs. 36.1%; P = 0.043). Logistic analysis results indicated that only LVEF (OR 0.92, 95% CI 0.87-0.93; P = 0.017) was associated with definite and probable ST.

CONCLUSIONS

The present study indicates that modern 2-DES technique for bifurcation lesions was comparatively safe with a low incidence of ST.

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.

Drug-Eluting Stents in Bifurcations

Background— The use of a drug-eluting stent (DES) has strongly limited the incidence of in-stent restenosis in bifurcation lesions; nevertheless, restenosis still remains a problem at the origin of the bifurcation side branch. The aim of this study is to analyze the consequences of the kissing postdilatation technique on 5 DESs, using microfocus x-ray computerized tomography and scanning electron microscopy.

Methods and Results— Five different DESs (Cypher, Cypher Select, Endeavor, Taxus Express, and Taxus Liberté) were deployed using kissing postdilatation protocols in a bench-top model. For all types of DES, microfocus x-ray computerized tomography analysis showed that (1) kissing postdilatation of the stent by 2 coaxial balloons caused elliptic deformation in the proximal segment and (2) kissing postdilatation technique reduced the ratio of potential metal to artery (manufacturer’s data/calculated ratio [%]: Cypher, 12.7/8.8; Cypher Select, 13.5/10.2; Endeavor, 19.0/13.3; Taxus Express, 20.5/4.7; Taxus Liberté, 17.9/12.5) and the potential drug application to area in the proximal segment, including the ostial struts (struts adjacent to and lying around the side branch ostium) (manufacturer’s data/calculated drug application [μg/mm 2 ]: Cypher, 1.4/1.0; Cypher Select, 1.4/1.1; Endeavor, 1.6/1.1; Taxus Express, 1.0/0.7; Taxus Liberté, 1.0/0.7). Scanning electron microscopy analysis showed a significantly greater coating damage to the ostial struts in all stents evaluated ( P <0.05).

Conclusions— Commercially available DESs subjected to simultaneous kissing balloon postdilatation in an unconstrained model may contribute to side branch ostial restenosis by proximal segment elliptic deformation and damage to the polymer coating.

Randomized trial of simple versus complex drug-eluting stenting for bifurcation lesions: the British Bifurcation Coronary Study: old, new, and evolving strategies

BACKGROUND

The optimal strategy for treating coronary bifurcation lesions remains a subject of debate. With bare-metal stents, single-stent approaches appear to be superior to systematic 2-stent strategies. Drug-eluting stents, however, have low rates of restenosis and might offer improved outcomes with complex stenting techniques.

METHODS AND RESULTS

Patients with significant coronary bifurcation lesions were randomized to either a simple or complex stenting strategy with drug-eluting stents. In the simple strategy, the main vessel was stented, followed by optional kissing balloon dilatation/T-stent. In the complex strategy, both vessels were systematically stented (culotte or crush techniques) with mandatory kissing balloon dilatation. Five hundred patients 64+/-10 years old were randomized; 77% were male. Eighty-two percent of lesions were true bifurcations (>50% narrowing in both vessels). In the simple group (n=250), 66 patients (26%) had kissing balloons in addition to main-vessel stenting, and 7 (3%) had T stenting. In the complex group (n=250), 89% of culotte (n=75) and 72% of crush (n=169) cases were completed successfully with final kissing balloon inflations. The primary end point (a composite at 9 months of death, myocardial infarction, and target-vessel failure) occurred in 8.0% of the simple group versus 15.2% of the complex group (hazard ratio 2.02, 95% confidence interval 1.17 to 3.47, P=0.009). Myocardial infarction occurred in 3.6% versus 11.2%, respectively (P=0.001), and in-hospital major adverse cardiovascular events occurred in 2.0% versus 8.0% (P=0.002), respectively. Procedure duration and x-ray dose favored the simple approach.

CONCLUSIONS

When coronary bifurcation lesions are treated, a systematic 2-stent technique results in higher rates of in-hospital and 9-month major adverse cardiovascular events. This difference is largely driven by periprocedural myocardial infarction. Procedure duration is longer, and x-ray dose is higher. The provisional technique should remain the preferred strategy in the majority of cases. Clinical Trial Registration Information- URL: http://www.clinicaltrials.gov. Unique identifier: NCT 00351260.

Coronary bifurcation lesions: innovative approaches and the future of bifurcation devices

Coronary bifurcation management is still a long way from an optimal solution with the current technologies. The long-lasting battle between the two-stent and provisional stenting strategies seems to have chosen the latter as winner, at least in most cases. However, with regard to other lesion subsets, interventions are often longer, more complex and charged with a worse outcome at both short- and medium-term follow-up. In the last decade, many dedicated devices have been developed to specifically address this condition. As in many similar cases, scientific commitment has returned few results, with these devices often being complex, time wasting and lacking evidence-based medicine. Here, we review the main technical features of this stent class and all the scientific data available.

Three-year outcome of drug-eluting stent implantation for coronary artery bifurcation lesions

OBJECTIVES

To compare the very long-term clinical outcomes of bifurcation lesions using the crush and the simultaneous kissing stent (SKS) techniques.

BACKGROUND

A variety of two-stent techniques have been used to treat coronary artery bifurcation lesions in the drug-eluting stent era, but the long-term clinical outcome of these approaches is not known.

METHODS

A total of 74 consecutive patients underwent bifurcation stenting using either the crush or SKS techniques. Mean patient age was 66.91 + or - 11.3 years; 26% were diabetic, and the left anterior descending/diagonal bifurcation was the most frequently treated lesion (68%).

RESULTS

In-hospital outcomes were not significantly different between groups. Over a median follow-up of 3.3 years, 1 patient in the SKS group and 3 patients in the crush group died (P = ns). Probable stent thrombosis leading to death according to the Academic Research Consortium definition occurred in 1 patient in the crush group. Mortality in the remaining 3 patients was noncardiac. Target lesion revascularization (TLR) occurred in 14 patients (40%) in the SKS group and 5 patients (12.8%) in the crush group (P = 0.015). Survival free from major adverse cardiac events (MACE) was significantly less in the SKS group and predominantly driven by TLR (60 vs. 88%, P = 0.001).

CONCLUSIONS

In conclusion, over a median of 3.3 years of follow-up, TLR and MACE are significantly lower in bifurcation lesions treated with the crush technique when compared with the SKS technique. Definite or probable stent thrombosis is rare with either technique.

Update on dedicated bifurcation stents

Coronary bifurcation lesions represent an area of ongoing challenge in interventional cardiology. Contemporary studies using drug-eluting stents report a reduction in main vessel (MV) restenosis; however, residual stenosis and restenosis at side-branch ostium remain an issue. Multiple two-stent bifurcation strategies exist, including T-stenting, V-stenting, simultaneous kissing stenting, culotte stenting, and crush stenting technique. Each strategy has its own advantages and disadvantages, but on the basis of results of numerous randomized trials, the provisional approach of implanting one stent on the main branch has became the default approach to most bifurcation lesions. Dedicated bifurcation stents have been designed to specifically address some of the shortcomings of the conventional percutaneous approach to bifurcation intervention. The majority of the devices are aimed at facilitating the provisional approach. Dedicated bifurcation stents should enable all operators to treat the side-branch ostium simultaneously with the main branch, preserving a safe, permanent access to side branch during the procedure. In the future, the use of these new devices will probably enhance the interaction between adequate mechanical scaffolding and accurate delivery of the appropriate dosage of any new antirestenosis drugs. There are currently 11 devices available that either have completed or are undergoing first-in-man trials. The development of further drug-eluting platforms and larger controlled studies should demonstrate their clinical applicability, efficacy, and safety before they are widely incorporated into daily practice.

Long-term clinical and angiographic outcomes of the sleeve technique on non-left-main coronary bifurcation lesions

AIMS

The purpose of this study was to examine the long-term results of the sleeve technique, which is a modification of the crush technique and capable of increasing the success of final kissing balloon inflation (FKB) in the treatment of non-left-main coronary bifurcation lesions.

METHODS AND RESULTS

Forty-five patients with 45 non-left-main coronary bifurcation stenoses were treated with drug-eluting stents (DES) using the sleeve technique and prospectively evaluated. Follow-up angiography was performed on 41 patients (91%) at nine months. The mean age of patient was 65 years with predominance of male (73%); FKB was successfully performed in all patients. Post-procedure myocardial infarction was observed in four patients, leading to an in-hospital major adverse cardiac event (MACE) rate of 9%. At angiographic follow-up, the late loss in the main vessel and side-branch was 0.18+/-0.26 mm and 0.29+/-0.27 mm, respectively. Binary angiographic restenosis was seen in two patients (4.7%) at main vessel and one patient (2.4%) at side-branch. At 1-year follow-up, there were two non-cardiac deaths and three patients needed revascularisation.

CONCLUSIONS

The use of the sleeve technique and DES in the treatment of non-left-main coronary bifurcation lesions is associated with a low angiographic restenosis, particularly at side branch ostium, and long-term safety.

A novel buddy balloon technique to recross a T-stented bifurcation

The T technique is not uncommonly used to stent bifurcation lesions. It requires recrossing into the side branch with a guidewire and balloon to perform final Kissing Balloon dilations, but recrossing can be difficult. We describe a case of bifurcation stenting where balloon recrossing following guidewire placement into the side branch proved very challenging, and was finally achieved via a combination of forward pressure on a low-profile balloon with its tip wedged at the stent struts along with simultaneous low-pressure inflation of a larger parallel balloon. This altered the stent architecture and also allowed for a more favorable vector of force transmission to allow recrossing and hence successful completion of the procedure.

Bifurcation disease: what do we know, what should we do?

The percutaneous treatment of coronary bifurcations has moved past an important milestone in that the 1- versus 2-stent debate appears to have been resolved. The provisional approach of implanting one stent on the main branch should be the default approach in most bifurcations lesions. Selection of the most appropriate strategy for an individual bifurcation is important. Some bifurcations require 1 stent, whereas others require the stenting of both branches. Irrespective of whether a 1- or 2-stent strategy is chosen, the results after bifurcation percutaneous coronary intervention (PCI) have dramatically improved. Dedicated bifurcation stents are an exciting new technology that may further simplify the management of bifurcation PCI and change some of these concepts.

[Clinical and angiographic outcomes after implantation of drug-eluting stents in bifurcation lesions with the crush stent technique]

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 degrees 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.

Impact of Bifurcation Technique on 2-Year Clinical Outcomes in 773 Patients With Distal Unprotected Left Main Coronary Artery Stenosis Treated With Drug-Eluting Stents

Background— Distal unprotected left main coronary artery (ULMCA) stenosis represents a technical challenge for interventional cardiologists. In this study, we compared 2-year clinical outcomes of different stenting strategies in patients with distal ULMCA stenosis treated with drug-eluting stents.

Methods and Results— The survey promoted by the Italian Society of Invasive Cardiology on ULMCA stenosis was an observational study on patients with ULMCA stenosis treated with percutaneous coronary intervention. In this study, we selected patients with distal ULMCA stenosis treated with drug-eluting stents. Seven hundred seventy-three patients were eligible for this study: 456 were treated with 1 stent (group 1) and 317 with 2 stents (group 2). The primary end point of the study was the incidence of major adverse cardiac events (MACEs), defined as the occurrence of mortality, myocardial infarction, and target lesion revascularization. During a 2-year follow-up, risk-adjusted survival free from MACE was significantly higher in patients in group 1 than in patients in group 2. The propensity-adjusted hazard ratio for the risk of 2-year MACE in patients in group 1 versus group 2 was 0.53 (95% CI, 0.37 to 0.76). The propensity-adjusted hazard ratio for the risk of 2-year cardiac mortality and myocardial infarction in patients in group 1 versus group 2 was 0.38 (95% CI, 0.17 to 0.85).

Conclusions— Compared with the 2-stent technique, the 1-stent technique is associated with a better 2-year MACE-free survival. The stenting strategy is a prognostic factor that should be taken into account when deciding the optimal revascularization treatment.