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

Advancements in Coronary Bifurcation Stenting Techniques: Insights From Computational and Bench Testing Studies

Coronary bifurcation lesions present complex challenges in interventional cardiology, necessitating effective stenting techniques to achieve optimal results. This literature review comprehensively examines the application of computational and bench testing methods in coronary bifurcation stenting, offering insights into procedural aspects, stent design considerations, and patient-specific characteristics. Structural mechanics finite element analysis, computational fluid dynamics, and multi-objective optimization are valuable tools for evaluating stenting strategies, including provisional side branch stenting and two-stenting techniques. We highlight the impact of procedural factors, such as balloon positioning and rewiring techniques, and stent design features on the outcome of percutaneous coronary interventions with stents. We discuss the importance of patient-specific characteristics in deployment strategies, such as bifurcation angle and plaque properties. This understanding informs present and future research and clinical practice on bifurcation stenting. Computational simulations are a continuously maturing advance that has significantly enhanced stenting devices and techniques for coronary bifurcation lesions over the years. However, the accurate account of patient-specific vessel and lesion characteristics, both in terms of anatomical and accurate physiological behavior, and their large variation between patients, remains a significant challenge in the field. In this context, advancements in multi-objective optimization offer significant opportunities for refining stent design and procedural practices.

Assessment of fractal ratio of vessel diameters in coronary bifurcation lesions by angiography and intravascular ultrasound

Physiological coronary branching at the bifurcation has a constant fractal ratio (FR) of the diameter of the mother vessel to the sum of daughter vessels on quantitative coronary angiography (QCA). We sought to investigate the FR of diseased coronary bifurcations using QCA and intravascular ultrasound (IVUS) and its impact on late lumen loss after percutaneous coronary intervention (PCI). In multicentre prospective studies of the J-REVERSE and 3D OCT Bifurcation Registry, 402 and 109 bifurcations treated with stenting that completed QCAs and IVUS examinations, respectively were analysed. FR was investigated at the reference sites pre-PCI and the minimum lumen diameter (MLD) post-PCI. In the QCA analysis, constant FR was observed in the pre-PCI reference (0.62 ± 0.08) and in the post-PCI MLD site (0.74 ± 0.10), which was greater (p < 0.05). In the IVUS analysis, the constant FR in the post-PCI MLD site (0.67 ± 0.06) was similar to that in the pre-PCI reference (0.66 ± 0.06) and close to the physiological FR value (0.678). The fourth quintile of pre-PCI reference FR in the IVUS analysis showed numerically least late lumen loss in proximal main vessel (MV) (0.16 ± 0.22 mm) and distal MV (0.13 ± 0.32 mm) and significantly less in the side branch compared to higher FR quintile (- 0.14 ± 0.27 mm vs. 0.10 ± 0.19 mm, p = 0.004), while no relationship was found in the QCA analysis. FR in the diseased coronary bifurcation was more accurately assessed on IVUS than on QCA, and the accomplishment of physiological FR might lead to less late lumen loss after bifurcation PCI.

Evaluation of Small Vessel Bifurcation Stenting Using the Double-Kissing Culotte and Culotte Technique in Acute Coronary Syndrome: 12-Month Clinical Outcomes

INTRODUCTION

Patients with small vessels who undergo percutaneous coronary intervention (PCI) with subsequent multiple implantation of drug-eluting stents remain at a higher risk of unfavorable outcomes. In complex cases where maintaining flow to all side branches is part of contemporary practice, using two-stent techniques may be appropriate. This study aims to evaluate the efficacy of double-kissing (DK) culotte technique in comparison to culotte technique in the context of small-vessel therapy in patients with acute coronary syndrome (ACS).

METHODS

This substudy of the Lower Silesia culotte Bifurcation Registry retrospectively analyzed patients who underwent ACS-PCI using DK culotte or culotte technique for bifurcation lesions in small vessels, defined as having at least one branch with a diameter of 2.75 mm or less. The primary endpoint was target lesion failure (TLF), a composite of cardiovascular death, target vessel myocardial infarction, or clinically driven target lesion revascularization (TLR) at 1-year follow-up. The secondary endpoint included major adverse cardiac events (MACE).

RESULTS

The DK culotte group (n = 49) and the culotte group (n = 52) were compared, with 12-month follow-up showing lower TLF in the DK culotte group (8.2% vs. 19.2%, p = 0.082). Similar results were observed for TLR (6.1% vs. 13.5%; p = 0.161), stent restenosis (4.1% vs. 9.6%; p = 0.203), and MACE (18.4% vs. 25%; p = 0.344).

CONCLUSION

For bifurcation lesions with a small-diameter artery, the DK culotte technique may reduce TLF and MACE compared to the culotte technique. However, given the limited sample size and the absence of statistical significance, these findings remain preliminary and require further investigation.

One year results of coronary bifurcation revascularization with the re-POT provisional sequential technique. The CABRIOLET registry

BACKGROUND

Re-POT (proximal optimization technique (POT)) is a simple provisional sequential technique for percutaneous coronary bifurcation revascularization with better arterial geometry respect compared to classical techniques. Re-POT has demonstrated excellent mechanical and short-term clinical results. The multicenter CABRIOLET registry (NCT03550196) evaluate the long-term clinical benefit of the re-POT sequence in non-selected patients.

METHODS

All consecutive patients presenting a coronary bifurcation lesion for which provisional stenting was indicated were included in 5 european centers. Re-POT strategy was systematically attempted. The primary endpoint was target lesion failure (TLF), comprising cardiac death, myocardial infarction, stent thrombosis and target lesion revascularization (TLR) at 12 months' follow-up. The secondary endpoints were the individual components of the primary endpoint, all-cause death, target vessel failure (TVF) and target vessel revascularization (TVR). Complex bifurcation was defined as Medina 0.1.1 or 1.1.1.

RESULTS

A total of 500 patients aged 67.7 ± 11.7 years, 78.4% male, were included from 2015 to 2019, 174 of whom (34.8%) were considered having complex bifurcation lesions. Bifurcations involved the left main in 35.2% of cases. The full re-POT sequence was systematically performed in all cases. At 1 year, TLF was 2.0% (1.7% in complex vs. 2.1% in non-complex bifurcation; p = NS), and TLR was 1.6%, (1.1% vs. 1.8% respectively; p = NS). TVF and TVR rates were 3.2% and 2.8%. On multivariate analysis, only multivessel disease was predictive of TLF at 1 year (OR = 1.66 (1.09-2.53), p = 0.02).

CONCLUSIONS

In this large prospective all-comer registry, provisional stenting with re-POT technique appeared safe and effective at 1 year, without anatomical bifurcation restriction.

Prognostic Impact of a Routine Six-Month Exercise Stress Test after Complex Left Main Bifurcation Percutaneous Intervention

The prognostic value of exercise stress test after complex left main (LM) coronary artery bifurcation (LM) stenting has been poorly investigated. To partially fill this gap in knowledge, we retrospectively analyzed the procedural and medical data of consecutive patients referred to our center for complex LM bifurcation disease between January 2008 and May 2018 who were treated using either single- or dual-stenting techniques. The prognostic impact of an exercise stress test, performed 6 months after the coronary intervention, was evaluated in 502 patients (316 males, mean age 70.3 ± 12.8 years, mean Syntax score 31.6 ± 6.3). At follow up after a mean of 37.1 ± 10.8 months (range 22.1-47.3 months), the target lesion failure (TLF) rate was 10.1% while stent thrombosis and cardiovascular mortality were 1.2 and 3.6%, respectively. A positive exercise stress test was detected at 6-month follow up in 42 out of 502 patients (8.4%); the incidence of a significant restenosis was 7.6% (n = 38). Patients with a negative exercise stress test at 6-month follow up had higher freedom from TLF and improved survival compared to those with a positive exercise stress test.

Longitudinal outcomes of final kissing balloon inflation in coronary bifurcation lesions treated with a single stent

Background

Final kissing balloon inflation (FKBI) is a percutaneous coronary intervention (PCI) technique that is considered mandatory to improve outcomes in two-stent strategies, but its use in single-stent bifurcation PCI remains controversial.

Methods

In this retrospective cohort study, we identified patients with coronary bifurcation lesions treated with one stent from January 2012 to March 2021 at a single academic medical center. Incidence rates per 1,000 patient-years (IR1000) were calculated for the outcomes of all-cause mortality, myocardial infarction (MI), stent thrombosis (ST), target lesion revascularization (TLR), coronary artery bypass graft (CABG), and cardiac readmission between patients who received FKBI and those who did not over a median follow up of 2.3 years. Studied outcomes were adjusted for all baseline clinical and procedural characteristics.

Results

This study included 893 consecutive patients of which 256 received FKBI and 637 did not. The IR1000 for MI were 51.1 and 27.6 for patients who received FKBI and patients who did not, respectively (adjusted HR = 2.44, p = 0.001). The IR1000 for death were 31.2 and 52.3 for patients who received FKBI and patients who did not, respectively (adjusted HR = 0.68, p = 0.141). The incidence rates of ST, TLR, CABG, and cardiac readmissions were similar between patients who received FKBI and those who did not.

Conclusions

These results suggest that performing FKBI in a one-stent technique was associated with higher rates of myocardial infarction, particularly in the first 6 months, and no difference in death, ST, TLR, CABG, and cardiac readmission rates.

Clinical outcomes following different stenting techniques for coronary bifurcation lesions: a systematic review and network meta-analysis of randomised controlled trials

BACKGROUND

Controversy still exists regarding the optimal treatment of coronary bifurcation lesions.

AIMS

We aimed to analyse the evidence from randomised controlled trials (RCTs) to compare outcomes following different bifurcation stenting techniques.

METHODS

We systematically searched for RCTs comparing different techniques published up to July 2022. We then conducted a pairwise meta-analysis to compare outcomes between provisional stenting (PS) versus upfront 2-stent techniques. Moreover, we performed a network meta-analysis (NMA) to compare all strategies with each other. The primary endpoint was major adverse cardiac events (MACE).

RESULTS

Twenty-four RCTs (6,890 patients) analysed PS, T-stenting, double-kissing (DK)-crush, crush, or culotte stenting. The pairwise meta-analysis did not reveal a significant difference between the PS and 2-stent techniques. However, the prespecified sensitivity analysis, which included RCTs exclusively enrolling patients with true bifurcation lesions, showed a lower rate of MACE following 2-stent techniques, and meta-regression indicated that a longer side branch lesion was associated with a greater benefit from the 2-stent strategy, which was the most apparent in RCTs with a mean lesion length >11 mm. NMA revealed that DK-crush was associated with the lowest MACE rate (odds ratio 0.47, 95% confidence interval: 0.36-0.62; p<0.01; PS as a reference).

CONCLUSIONS

Overall, 2-stent techniques were not significantly better than PS in terms of clinical outcomes. However, the results of the sensitivity analysis suggested that there might be a benefit of a 2-stent approach in selected patients with true bifurcation lesions, especially in the case of long side branch lesions. An NMA revealed that DK-crush was associated with the lowest event rates when compared with other techniques.

Impact of coronary bifurcation angle on stent malapposition in a randomized comparison between proximal optimization technique followed by side branch dilatation and kissing balloon inflation

Background

The impact of coronary bifurcation angle (BA) on incomplete stent apposition (ISA) after crossover stenting followed by side branch (SB) intervention has not been established.

Methods

A total of 100 crossover stentings randomly treated with proximal optimization technique followed by short balloon dilation in the SB (POT-SBD group, 48 patients) and final kissing balloon technique (KBT group, 52 patients) were analyzed in the PROPOT trial. Major ISA with maximum distance > 400 μm and its location was determined using optical coherence tomography before SB intervention and at the final procedure. The BA was defined as the angle between the distal main vessel and SB. Optimal POT was determined when the difference in stent volume index between the proximal and distal bifurcation was greater than the median value (0.86 mm3/mm) before SB intervention.

Result

Major ISA was more frequently observed in the POT-SBD than in the KBT group (35% versus 17%, p < 0.05). In the POT-SBD group, worsening ISA after SBD was prominent at the distal bifurcation. The BA was an independent predictor of major ISA (odds ratio 1.04, 95% confidence interval 1.00-1.07, p < 0.05) with a cut-off value of 59.5° (p < 0.05). However, the cases treated with optimal POT in the short BA (<60°) indicated the lowest incidence of major ISA. In the KBT group, BA had no significant impact.

Conclusion

A wide BA has a potential risk for the occurrence of major ISA after POT followed by SBD in coronary bifurcation stenting.

Success rate and influencing factors of a balloon-push technique: A new technique to remove side branch-jailed struts under three-dimensional optical coherence tomography guidance

BACKGROUND

Kissing balloon inflation with distal guide wire recross can cause severe stent deformation depending on the stent link location with respect to the carina. The balloon-push technique, by which an inflated balloon is forced into the SB from the proximal main vessel (MV), is a feasible way to remove jailed struts without causing severe stent deformation.

AIMS

We investigated the procedural success rate, patterns of jailed strut removal at side branch (SB) orifices, factors related to failure of jailed strut removal, and follow-up angiogram results of the balloon-push technique.

METHODS

Between September 2015 and December 2020, 51 bifurcation stenting cases in which the balloon-push technique was used were enrolled. Based on three-dimensional optical coherence tomography images, strut removal with 1 stent crown length was defined as successful. Strut removal patterns were classified into two types: parallel-slide type (stent struts shifted distally into the MV lumen without inversion) and under-carina type (stent struts shifted distally under the carina with strut inversion or strut slide).

RESULTS

Procedural success was attained in 39 cases (success rate: 76.5%). Parallel-slide type and under-carina type occurred in 43% and 33% of cases, respectively. Factors related to failure were trifurcation lesions and a smaller pushed balloon-SB artery ratio compared with those in success cases (0.95 ± 0.18 vs. 1.10 ± 0.22, p = 0.032). Follow-up angiography was performed in 37 cases, and 2 cases had binary in-stent restenosis.

CONCLUSIONS

Removal of jailed struts with the balloon-push technique was feasible, without severe stent deformation, in bifurcation stentings.

Meta-Analysis of Provisional Versus Systematic Double-Stenting Strategy for Left Main Bifurcation Lesions

OBJECTIVE

We sought to compare the clinical outcomes with provisional versus double-stenting strategy for left main (LM) bifurcation percutaneous coronary intervention (PCI).

BACKGROUND

Despite two recent randomized controlled trials (RCTs) and several observational reports, the optimal LM bifurcation PCI technique remains controversial.

METHODS

PubMed, Cochrane Central Register of Controlled-Trials (CENTRAL), Clinicaltrials.gov, International Clinical Trial Registry Platform were leveraged for studies comparing PCI bifurcation techniques for LM coronary lesions using second-generation drug eluting stents (DES). The primary outcome was major adverse cardiovascular events (MACE). Secondary outcomes of interest were all-cause mortality, cardiovascular mortality, myocardial infarction (MI), target vessel or lesion revascularization, and stent thrombosis.

RESULTS

Two RCTs and 10 observational studies with 7105 patients were included. Median follow-up duration was 42 months (IQR: 25.7). Double stenting was associated with a trend towards higher incidence of MACE (odds ratio [OR] 1.20; 95 % confidence interval [CI] 0.94 to 1.53) compared with provisional stenting. This was mainly driven by higher rates of target lesion revascularization (TLR) (OR 1.50; 95 % CI 1.07 to 2.11). There were no statistically significant differences in the incidence of all-cause mortality, cardiovascular mortality, MI, or stent thrombosis. On subgroup analysis according to the study type, provisional stenting was associated with lower MACE and TLR in observational studies, but not in RCTs.

CONCLUSION

For LM bifurcation PCI using second-generation DES, a provisional stenting strategy was associated with a trend towards lower incidence of MACE driven by statistically significant lower rates of TLR, compared with systematic double stenting. These differences were primarily driven by observational studies. Further RCTs are warranted to confirm these findings.

Technical Complications of Coronary Bifurcation Percutaneous Interventions

Coronary bifurcation percutaneous interventions (PCI) comprise a challenging subset of patients with coronary artery disease. Beyond the well-known debate about single versus double stent strategies, which have different outcomes on mid- and long-term follow up, both strategies may be subject, although rarely, to several different technical complications, rarely reported in clinical trials, which need to be defined, classified, and understood by cardiovascular professionals involved in the management of patients with coronary bifurcation disease. The present paper aims to broaden the knowledge of the range of intraprocedural complications and relative treatment during PCI of coronary bifurcations.

Provisional or 2-Stent Technique for Bifurcation Lesions in the Second-Generation Drug-Eluting Stent Era

Background

For bifurcating coronary lesions, a provisional stent technique is recommended compared with a routine 2-stent strategy. However, much of these data are from trials involving first-generation drug-eluting stents (DES) or bare-metal stents where the risk of restenosis with the 2-stent technique is higher. We investigated the efficacy of various 2-stent techniques versus a provisional stent technique for bifurcation lesions with newer-generation DES.

Methods

PubMed and Embase were searched through May 2022 for randomized control trials investigating bifurcation percutaneous coronary intervention techniques using newer-generation DES, and a meta-analysis was conducted. The primary end point was major adverse cardiovascular events (MACE) at the longest reported follow-up time.

Results

Our study identified 13 randomized control trials including 4041 patients. Compared with the provisional technique, 2-stent techniques significantly decreased MACE (hazard ratio [HR], 0.76; 95% CI, 0.59-0.97; P = .03), target vessel myocardial infarction (HR, 0.38; 95% CI, 0.20-0.71; P = .002), and target vessel revascularization (HR, 0.66; 95% CI, 0.47-0.93; P = .02). There were no significant differences in all-cause mortality (HR, 0.94; 95% CI, 0.62-1.45; P = .79), cardiovascular mortality (HR, 0.82; 95% CI, 0.49-1.38; P = .45), myocardial infarction (HR, 1.00; 95% CI, 0.73-1.37; P = .99), and stent thrombosis (HR, 0.86; 95% CI, 0.52-1.44; P = .58). Of the 2-stent techniques, the double kissing crush technique significantly decreased MACE and target lesion revascularization than other 2-stent techniques.

Conclusions

In this era of newer-generation DES, a 2-stent approach, especially the double kissing crush technique, is superior to a provisional stenting technique for a bifurcation lesion, with a significant reduction in MACE, target vessel myocardial infarction, and revascularization.

Physiological Approach for Coronary Artery Bifurcation Disease: Position Statement by Korean, Japanese, and European Bifurcation Clubs

Coronary artery bifurcation lesions are frequently encountered in cardiac catheterization laboratories and are associated with more complex procedures and worse clinical outcomes than nonbifurcation lesions. Therefore, anatomical and physiological assessment of bifurcation lesions before, during, and after percutaneous coronary intervention is of paramount clinical importance. Physiological assessment can help interventionalists appreciate the hemodynamic significance of coronary artery disease and guide ischemia-directed revascularization. However, it is important to understand that the physiological approach for bifurcation disease is more important than simply using physiological indexes for its assessment. This joint consensus document by the Korean, Japanese, and European bifurcation clubs presents the concept of a physiological approach for coronary bifurcation lesions, as well as current knowledge, practical tips, pitfalls, and future directions of applying physiological indexes in bifurcation percutaneous coronary intervention. This document aims to guide interventionalists in performing appropriate physiology-based assessments and treatment decisions for coronary bifurcation lesions.

Single versus Double Stenting in NSTEMI Patients with Complex Left Main Bifurcation Disease

Background: Among patients with non-ST-segment elevation myocardial infarction (NSTEMI) the presence of a bifurcation left main (LM) disease represents a particular subset graved by both clinical and technical challenges. We sought to assess the long-term outcomes of patients with NSTEMI treated either by single or double stent strategy, having an LM bifurcation culprit lesion. Methods: We retrospectively analyzed the procedural and medical data of consecutive patients referred to our center for NSTEMI due to complex LM bifurcation disease as the culprit lesion, treated using either single or dual stenting (provisional stenting, T or T-and-Protrusion (TAP), Culotte, and Nano-inverted-T (NIT)) techniques between January 2008 and May 2018. Target lesion failure (TLF) was defined as the composite of cardiovascular death, target-vessel myocardial infarction (MI), and clinically driven target lesion revascularization (TLR). Results: Four hundred and forty-five patients (54.1% males, mean age 70.3 ± 12.8 years, mean Syntax score 31.6 ± 6.3) were evaluated. Of these, 155 patients (34.8%) were treated using a single stent while the remaining were treated with a double stent strategy. After a mean follow-up of 37.1 months (IQR 22.1-39.3), TLF rate was 8.7% (n = 39): 5/155 (3.2%) in the crossover group; 10/53 (18.8%) in T/TAP group, 14/89 (15.7%) in the culotte group, and 10/148 (6.7%) in the NIT group of patients. Cardiovascular mortality rate was 2.9% (n = 13) while stent thrombosis was 0.89% (n = 4). On multivariate analysis dyslipidemia, Syntax score > 25, triple vessel disease, additional LM ostial, or LM body lesions and the use of Rotablator, were independent predictors of TLF. Conclusions: Either a single or double stent strategy resulted in low rates of TLF, cardiovascular death, and stent thrombosis in the long-term period in NSTEMI LM patients with contraindications or refusal of surgery. A single stent strategy appeared to have a slightly better outcome compared to a 2-stent strategy.

Systematic Review and Network Meta-Analysis Comparing Bifurcation Techniques for Percutaneous Coronary Intervention

Background Bifurcation lesions account for 20% of all percutaneous coronary interventions and represent a complex subset which are associated with lower procedural success and higher rates of restenosis. The ideal bifurcation technique, however, remains elusive. Methods and Results Extensive search of the literature was performed to pull data from randomized clinical trials that met predetermined inclusion criteria. Conventional meta-analysis produced pooled relative risk (RR) and 95% CI of 2-stent technique versus provisional stent on prespecified outcomes. Both frequentist and Bayesian network meta-analyses were performed to compare bifurcation techniques. A total of 8318 patients were included from 29 randomized clinical trials. Conventional meta-analysis showed no significant differences in all-cause mortality, cardiac death, major adverse cardiac events, myocardial infarction, stent thrombosis, target lesion revascularization, and target vessel revascularization between 2-stent techniques and provisional stenting. Frequentist network meta-analysis revealed that double kissing crush was associated with lower cardiac death (RR, 0.57; 95% CI, 0.38-0.84), major adverse cardiac events (RR, 0.50; 95% CI, 0.39-0.64), myocardial infarction (RR, 0.60; 95% CI, 0.39-0.90), stent thrombosis (RR, 0.50; 95% CI, 0.28-0.88), target lesion revascularization, and target vessel revascularization when compared with provisional stenting. Double kissing crush was also superior to other 2-stent techniques, including T-stent or T and protrusion, dedicated bifurcation stent, and culotte. Conclusions Double kissing crush was associated with lower risk of cardiac death, major adverse cardiac events, myocardial infarction, stent thrombosis, target lesion revascularization, and target vessel revascularization compared with provisional stenting and was superior to other 2-stent techniques. Superiority of 2-stent strategy over provisional stenting was observed in subgroup meta-analysis stratified to side branch lesion length ≥10 mm.

Vascular healing after kissing balloon inflation: Nine-month 3D optical coherence tomography analysis in corelab

Background

The jailing strut configuration with link-free and distal guidewire recrossing (LFD) at the side branch orifice (SBO) reduces incomplete stent apposition (ISA) after kissing balloon technique (KBT) in crossover stenting of coronary bifurcation lesions (CBLs). However, data regarding vascular healing after KBT are lacking. We investigated vascular healing 9 months after crossover stenting followed by KBT with optical coherence tomography (OCT) guidance in a prospective multicenter registry.

Methods

Fifty-nine patients with CBLs (LFD, 35 patients; non-LFD, 24 patients) were studied. The jailing configuration of the SB and the wire-recrossing position, incidence of ISA and uncovered struts, and neointima unevenness score (NUS) in the main vessel (MV) after 9 months were determined by off-line 3D-OCT in the core laboratory.

Results

The ISA rate was significantly higher at the SB ostium and distal MV after KBT in the non-LFD group, compared to the LFD group. After 9 months, incidence of ISA (18.3 ± 18.2 vs. 6.0 ± 8.7%, p < 0.01) and uncovered struts (8.7 ± 9.9 vs. 4.7 ± 7.3 %, p = 0.08) were higher at the SB ostium with higher SB restenosis in the non-LFD group. In distal MV, NUS was significantly higher (3.1 ± 1.1 vs. 2.5 ± 0.6, p < 0.05). In true-CBLs, an increase in uncovered struts and ISA rate was prominent in the proximal MV and opposite SB. No differences were observed in the 9-month clinical outcomes.

Conclusion

Visualization of the wire recrossing point and the SB-jailing strut pattern by OCT plays an important role to optimize the KBT in CBL stenting, resulting in favorable mid-term vascular healing.

Impact of Left Ventricular Ejection Fraction on Procedural and Long-Term Outcomes of Bifurcation Percutaneous Coronary Intervention

The association of left ventricular ejection fraction (LVEF) with procedural and long-term outcomes after state-of-the-art percutaneous coronary intervention (PCI) of bifurcation lesions remains unsettled. A total of 5,333 patients who underwent contemporary coronary bifurcation PCI were included in the intercontinental retrospective combined insights from the unified RAIN (veRy thin stents for patients with left mAIn or bifurcatioN in real life) and COBIS (COronary BIfurcation Stenting) III bifurcation registries. Of 5,003 patients (93.8%) with known baseline LVEF, 244 (4.9%) had LVEF <40% (bifurcation with reduced ejection fraction [BIFrEF] group), 430 (8.6%) had LVEF 40% to 49% (bifurcation with mildly reduced ejection fraction [BIFmEF] group) and 4,329 (86.5%) had ejection fraction (EF) ≥50% (bifurcation with preserved ejection fraction [BIFpEF] group). The primary end point was the Kaplan-Meier estimate of major adverse cardiac events (MACEs) (a composite of all-cause death, myocardial infarction, and target vessel revascularization). Patients with BIFrEF had a more complex clinical profile and coronary anatomy. No difference in procedural (30 days) MACE was observed across EF categories, also after adjustment for in-study outcome predictors (BIFrEF vs BIFmEF: adjusted hazard ratio [adj-HR] 1.39, 95% confidence interval [CI] 0.37 to 5.21, p = 0.626; BIFrEF vs BIFpEF: adj-HR 1.11, 95% CI 0.25 to 2.87, p = 0.883; BIFmEF vs BIFpEF: adj-HR 0.81, 95% CI 0.29 to 2.27, p = 0.683). BIFrEF was independently associated with long-term MACE (median follow-up 21 months, interquartile range 10 to 21 months) than both BIFmEF (adj-HR 2.20, 95% CI 1.41 to 3.41, p <0.001) and BIFpEF (adj-HR 1.91, 95% CI 1.41 to 2.60, p <0.001) groups, although no difference was observed between BIFmEF and BIFpEF groups (adj-HR 0.87, 95% CI 0.61 to 1.24, p = 0.449). In conclusion, in patients who underwent PCI of a coronary bifurcation lesion according to contemporary clinical practice, reduced LVEF (<40%), although a strong predictor of long-term MACEs, does not affect procedural outcomes.

Meta-Analysis Comparing Outcomes With Bifurcation Percutaneous Coronary Intervention Techniques

There have been mixed results regarding the efficacy and safety of various percutaneous coronary intervention bifurcation techniques. An electronic search of Medline, Scopus, and Cochrane databases was performed for randomized controlled trials that compared the outcomes of any bifurcation techniques. We conducted a pairwise meta-analysis comparing the 1-stent versus 2-stent bifurcation approach, and a network meta-analysis comparing the different bifurcation techniques. The primary outcome was major adverse cardiac events (MACEs). The analysis included 22 randomized trials with 6,359 patients. At a weighted follow-up of 25.9 months, there was no difference in MACE between 1-stent versus 2-stent approaches (risk ratio [RR] 1.20, 95% confidence interval [CI] 0.92 to 1.56). Exploratory analysis suggested a higher risk of MACE with a 1-stent approach in studies using second-generation drug-eluting stents, if side branch lesion length ≥10 mm, and when final kissing balloon was used. There was no difference between 1-stent versus 2-stent approaches in all-cause mortality (RR 0.95, 95% CI 0.69 to 1.30), cardiovascular mortality (RR 1.07, 95% CI 0.68 to 1.68), target vessel revascularization (TVR) (RR 1.22, 95% CI 0.90 to 1.65), myocardial infarction (MI) (RR 1.04, 95% CI 0.69 to 1.56) or stent thrombosis (RR 1.10, 95% CI 0.68 to 1.78). Network meta-analysis demonstrated that double kissing crush technique was associated with lower MACE, MI, TVR, and target lesion revascularization, whereas culotte technique was associated with higher rates of stent thrombosis. In this meta-analysis of randomized trials, we found no difference between 1-stent versus 2-stent bifurcation percutaneous coronary intervention approaches in the risk of MACE during long-term follow-up. Among the various bifurcation techniques, double kissing crush technique was associated with lower rates of MACE, target lesion revascularization, TVR, and MI.

Impact of directional coronary atherectomy followed by drug-coated balloon strategy to avoid the complex stenting for bifurcation lesions

Although the simple single stenting rather than complex double stenting is recommended on percutaneous coronary intervention (PCI) for bifurcation lesions, double stenting cannot always be avoided. We investigated the impact of directional coronary atherectomy (DCA), followed by drug-coated balloon (DCB) treatment to reduce the number of stents and avoid complex stenting in PCI for bifurcation lesions and short-term patency. DCA treatment without stents was attempted for 27 bifurcation lesions in 25 patients, of those, 26 bifurcation lesions in 24 patients were successfully treated and 3-month follow-up angiography and optical coherence tomography (OCT) were performed. Sixteen lesions (59.3%) were related to left main trunk distal bifurcations, and 7 (25.9%) were true bifurcation lesions. Among the true bifurcation lesions, 4 lesions (57.1%) needed 1 stent, and the other 3 lesions (42.9%) needed no stents. Among the non-true bifurcation lesions, 1 lesion (5.0%) needed bailout stent and other lesions (95.0%) needed no stents. According to DCA followed by DCB treatment, the angiographic mean diameter stenosis improved from 65.5 ± 15.0% to 7.8 ± 9.8%, and the mean plaque area in intravascular ultrasound improved from 80.4 ± 10.5% to 39.0 ± 11.5%, respectively. Angiographic and OCT late lumen loss values were 0.2 ± 0.6 mm and 1.4 ± 1.9 mm, respectively. No patient had in-hospital major adverse cardiac events (MACE) and 3-month MACE. In conclusion, compared with standard provisional side branch stenting strategy, DCA followed by DCB treatment might reduce the number of stents, avoid complex stenting for major bifurcation lesions and provide good short-term outcomes.

Evolution of the Crush Technique for Bifurcation Stenting

Bifurcation lesions are frequently encountered, associated with greater procedural complexity and consequently are at higher risk for restenosis and stent thrombosis. Early trials in bifurcation percutaneous coronary intervention favored a provisional stenting approach, but contemporary randomized trials have highlighted potentially superior outcomes using a double-kiss crush technique in unprotected distal left main stem bifurcation lesions. Although the evidence is greatest for double-kiss crush, many operators favor a mini-crush or nano-crush single-kiss approach. In this review, the authors describe the iterations of the crush technique and the evidence for each and review general principles for bifurcation percutaneous coronary intervention.

Proximal optimisation technique versus final kissing balloon inflation in coronary bifurcation lesions: the randomised, multicentre PROPOT trial

BACKGROUND

Clinical implications of the proximal optimisation technique (POT) for bifurcation lesions have not been investigated in a randomised controlled trial.

AIMS

This study aimed to investigate whether POT is superior in terms of stent apposition compared with the conventional kissing balloon technique (KBT) in real-life bifurcation lesions using optical coherence tomography (OCT).

METHODS

A total of 120 patients from 15 centres were randomised into two groups - POT followed by side branch dilation or KBT. Finally, 57 and 58 patients in the POT and KBT groups, respectively, were analysed. OCT was performed at baseline, immediately after wire recrossing to the side branch, and at the final procedure.

RESULTS

The primary endpoint was the rate of malapposed struts assessed by the final OCT. The rate of malapposed struts did not differ between the POT and KBT groups (in-stent proximal site: 10.4% vs 7.7%, p=0.33; bifurcation core: 1.4% vs 1.1%, p=0.67; core's distal edge: 6.2% vs 5.3%, p=0.59). More additional treatments were required among the POT group (40.4% vs 6.9%, p<0.01). At one-year follow-up, only one patient in each group underwent target lesion revascularisation (2.0% vs 1.9%).

CONCLUSIONS

POT followed by side branch dilation did not show any advantages over conventional KBT in terms of stent apposition; however, excellent midterm clinical outcomes were observed in both strategies.

Feasibility and efficacy of an ultra-short side branch-dedicated balloon in coronary bifurcation stenting

BACKGROUND

Side branch (SB) dilation with an ultra-short balloon after main vessel (MV) stenting may minimise stent failure in coronary bifurcation lesions.

AIMS

We sought to investigate the feasibility and efficacy of the Glider balloon (GB), a side branch (SB)-dedicated balloon 4 mm in length, in coronary bifurcation stenting.

METHODS

In bench testing, stent configuration was examined with micro-focus computed tomography after crossover stenting followed by GB dilation or kissing balloon inflation (KBI). In the clinical study we performed GB dilatation after MV stenting for 207 lesions in 194 patients. Failure of the GB dilation and additional procedures due to inducible stent failure were investigated as well as adverse cardiac events at 1-year follow-up.

RESULTS

In bench testing GB dilation maintained cross-sectional stent area without significant deformation and presented effective jailed strut removal in a high-angled bifurcation model. In the clinical study the cohort included left main, true bifurcation lesion, and two-stent treatment in 42.0%, 45.9%, and 14.0%, respectively. The proximal optimisation technique (POT) or POT-like inflation was performed in 82.1%. GB crossing failure, SB stenting due to dissection, and stent deformation requiring correction by KBI or MV dilation occurred in 8.7%, 1.4%, and 5.8%, respectively. Finally, simple GB dilation without KBI was completed in 91.8% for SB dilation. At one-year follow-up, target lesion revascularisation, cardiac death, myocardial infarction, and stent thrombosis were found in 7.2%, 2.1%, 2.1%, and 1.0%, respectively.

CONCLUSIONS

Simple GB dilation after adequate expansion of the proximal MV stent provided acceptable acute and long-term results as an alternative to KBI.

5-Year Outcome of Simple Crossover Stenting in Coronary Bifurcation Lesions Compared With Side Branch Opening

Background

The optimal side branch (SB) treatment strategy after simple crossover stenting in bifurcation lesions is still controversial.

Objectives

The purpose of this study was to compare the long-term outcomes of a 1-stent strategy with simple crossover alone versus with an additional SB–opening procedure in patients with left main (LM) and non-LM coronary bifurcation lesions.

Methods

Patients who underwent percutaneous coronary intervention with a 1-stent strategy for bifurcation lesions including LM were selected from the COBIS (Coronary Bifurcation Stenting) III registry and divided into the simple crossover–alone group and SB-opening group. Clinical outcomes were assessed by the 5-year rate of target lesion failure (a composite of cardiac death, target vessel myocardial infarction, and target lesion repeat revascularization).

Results

Among 2,194 patients who underwent the 1-stent strategy, 1,685 (76.8%) patients were treated with simple crossover alone, and 509 (23.2%) patients were treated with an additional SB-opening procedure. Although the baseline SB angiographic disease was more severe in the SB-opening group, the final lumen diameter of the SB was larger. The 5-year observed target lesion failure rate was similar between the 2 groups (7.0% in the simple crossover vs. 6.7% in SB-opening group; hazard ratio: 0.99; 95% confidence interval: 0.66 to 1.48; p = 0.947), even in the subgroup analyses including LM (9.5% vs. 11.3%; p = 0.442) and true bifurcation (5.3% vs. 7.8%; p = 0.362). The results were not changed after an inverse probability of treatment weighting adjustment. There was no difference in the overall and SB-related target lesion revascularization rate in both groups.

Conclusions

The long-term clinical outcome of the 1-stent strategy with simple crossover alone for coronary bifurcation lesions was acceptable compared to those of additional SB-opening procedures. (Korean Coronary Bifurcation Stenting [COBIS] Registry III [COBIS III]; NCT03068494)

Feasibility, safety and long-term outcomes of complex left main bifurcation treatment using the nano-inverted-t stenting: a multicentre prospective registry

The role of double stenting techniques in distal bifurcation left main (LM) disease has gaining interest over the latest years. We present the 3-year multicentre registry outcomes of dual stenting using ultra-thin strut stents and the Nano-Inverted-T (NIT) technique in complex unprotected true LM bifurcation disease. We analysed the procedural and medical data of consecutive patients enrolled between 1st January 2014 and 1st December 2019 in a multicentre registry for complex LM bifurcation disease treated with the double stenting technique called NIT due contraindications and/ or refusal to surgical treatment. Target lesion failure (TLF) was defined as the composite of cardiovascular death, target-vessel MI (TVMI) and clinically driven target lesion revascularization (TLR). Among two hundred-ninety-five patients (138 males, mean age 70.3 ± 12.8 years), post-operative success was achieved in 100% of cases. Contrast volume, procedural time, and radiation exposure were 139.2 ± 23.4 ml, 15.3 ± 4.9 min, and 1080 ± 1034 cGy/m2, respectively. At a mean follow-up of 39.5 ± 0.6 months TLF rate was 6.1% (n = 18) while TLR and cardiovascular mortality rates were 3.0 (n = 9) and 2.6% (n = 8), respectively. Clinically-driven angiographic follow-up was available in 26.4% of patients at a mean time from the procedure of 7.5 ± 0.4 months. Clinically restenosis rate was 3.3%.Revascularization of complex LM bifurcation disease using the NIT double stenting technique resulted feasible and safe with a low incidence of TLF, excellent survival rate and no stent thrombosis.

Stenting techniques for coronary bifurcation lesions: Evidence from a network meta-analysis of randomized clinical trials

OBJECTIVES

We conducted a systematic review and network meta-analysis of available randomized clinical trials (RCTs) to compare cardiovascular outcomes involving stenting techniques in coronary bifurcation lesions.

BACKGROUND

Although provisional stenting of the main branch and balloon angioplasty of the side branch is considered the standard approach, the use of two stents is often pursued with a wide variety of bifurcation stenting techniques available.

METHODS

We searched PubMed, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and Clinicaltrials.gov from inception to December 2018. We performed a frequentist network meta-analysis to estimate relative risks (RR) of death, major adverse cardiovascular events (MACE), target vessel revascularization (TVR), target lesion revascularization (TLR), and stent thrombosis (ST) among different two stent bifurcation techniques.

RESULTS

We identified 14 studies, yielding data on 4,285 patients. Double Kissing (DK) Crush and Mini-crush were associated with significant reductions in MACE, TVR, and TLR when compared with the Provisional stenting (RR 0.31-0.55 [all p < .01] and RR 0.42-0.45 [all p < .02], respectively) and with the remaining bifurcation techniques (RR 0.44-0.55 [all p < .05] for DK Crush and RR 0.37-0.45 [all p < .05] for Mini-crush). In addition, Culotte and Crush were associated with an increased risk for ST compared to Provisional stenting (RR 3.25-4.27 [both p < .05]) and to DK crush (RR 3.02-3.99 [both p < .05]).

CONCLUSIONS

DK crush and mini-crush were found to be associated with fewer events and complications compared to the other techniques reviewed, including the Provisional approach. Further, Culotte and Crush were associated with an increased risk of stent thrombosis when compared to the Provisional approach.

Association of Side-Branch Treatment and Patient Factors in Left Anterior Descending Artery True Bifurcation Lesions: Analysis from the GRAND-DES Pooled Registry

Methods

Patients undergoing PCI to left anterior descending (LAD) bifurcation lesions with contemporary DES were analyzed from a nationwide registry. Baseline risk was assessed using the Age, Creatinine, and Ejection Fraction (ACEF) score. Target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, and target lesion revascularization, was assessed at 3 years.

Results

Among 1,089 patients with LAD bifurcation lesions, 548 (50.3%) patients underwent SB treatment. The SB treatment group showed a nonsignificant, but numerically lower rate of 3-year TLF (6.6% vs. 9.2%, HR 0.75, 95%CI 0.44–1.28, p = 0.29). In patients with low pretreatment risk (ACEF<1.22), SB treatment was associated with a lower rate of 3-year TLF (HR 0.43, 95%CI 0.19–0.96, p = 0.04), while no significant difference was observed in patients with high risk (ACEF≥1.22). The difference in the low risk group was mostly driven by target lesion revascularization (HR 0.24, 95%CI 0.08–0.75, p = 0.01).

Conclusions

SB treatment for LAD bifurcation lesions showed favorable long-term outcomes compared with main-branch-only intervention, especially in patients with low pretreatment risk.

A Randomized Trial Evaluating Online 3-Dimensional Optical Frequency Domain Imaging-Guided Percutaneous Coronary Intervention in Bifurcation Lesions

Supplemental Digital Content is available in the text.

Background:

Clinical implications of online 3-dimensional optical frequency domain imaging (3D-OFDI)-guided stenting for bifurcation lesions have not been investigated in the randomized controlled trials. The purpose of this study was to determine whether online 3D-OFDI-guided stenting is superior to angiography-guided percutaneous coronary intervention (PCI) in terms of incomplete stent apposition at the bifurcation segment.

Methods:

The OPTIMUM trial (Online 3-Dimensional Optical Frequency Domain Imaging to Optimize Bifurcation Stenting Using UltiMaster Stent) was a randomized, multicenter clinical trial. Eligible patients had an angiographically significant stenosis in the bifurcation lesion treated with a provisional single stent strategy using the Ultimaster sirolimus eluting stent. Patients were randomly allocated to either online 3D-OFDI-guided or angiography-guided PCI. Patients randomized to 3D-OFDI guidance underwent online 3D-OFDI assessment after rewiring into the jailed side branch after stenting and proximal optimization technique, while in the angiography guidance arm, rewiring was performed using conventional fluoroscopic/angiographic guidance. The primary end point of this trial was the postprocedural average percentage of malapposed struts per lesion assessed by OFDI in the confluence zone of the main and side branches.

Results:

Between June 8, 2017 and September 26, 2018, 110 patients with 111 bifurcation lesions were randomized at 4 Japanese centers. Of these, 56 patients with 57 lesions were treated with 3D-OFDI-guided PCI, whereas 54 patients with 54 lesions were treated with angiography-guided PCI. In the 3D-OFDI guidance arm, the feasibility of online 3D-OFDI was 98.2%. The average percentage of incomplete stent apposition per lesion at bifurcation was lower in the 3D-OFDI guidance arm than that in the angiography guidance arm (19.5±15.8% versus 27.5±14.2%, P=0.008). The superiority of the 3D-OFDI guidance arm was also confirmed in the strut level analysis (odds ratio: 0.54 [95% CI, 0.36–0.81]; P=0.003).

Conclusions:

Online 3D-OFDI-guided bifurcation PCI was superior to angiography-guided bifurcation PCI in terms of acute incomplete stent apposition at bifurcation.

Registration:

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02972489.

Clinical outcomes following percutaneous coronary intervention for bifurcation lesions: kissing balloon inflation vs. sequential dilation

Percutaneous coronary intervention for bifurcation lesions remains challenging, with there being several debatable issues, including the requirement for kissing balloon inflation (KBI). The objective of this study was to assess the clinical outcomes following single crossover stent implantation with KBI or sequential dilation alone. Data were examined for 255 non-left main bifurcation lesions (246 patients) treated with single crossover stent implantation, followed by side branch (SB) strut dilation with KBI (n = 74 lesions) or sequential dilation (n = 181 lesions) in three hospitals. Target lesion revascularization (TLR) was the primary endpoint. There was no significant difference in the pre-procedural reference diameter of both the main vessel (MV) and SB between the KBI and sequential dilation groups. However, MV post-dilation balloon size was smaller with lower pressure and post-procedural minimal lumen diameter was significantly smaller in the KBI group. During the median follow-up period of approximately 3 years, TLR incidence was significantly higher in the KBI group than in the sequential dilation group; in particular, the TLR rate at the distal MV was higher in the former. For bifurcation lesions treated with single crossover stent implantation, the TLR rate was higher after KBI than after sequential dilation; this was mainly due to higher revascularization in the distal MV. For bifurcation lesions treated with KBI, MV post-dilation balloon diameter tended to be smaller with lower pressure, which might lead to poorer stent expansion and a higher TLR rate.

Asia Pacific consensus document on coronary bifurcation interventions

Coronary bifurcation intervention is common but complex. Progress in this field has been made in recent years with considerable contribution from the Asia Pacific (APAC) region. However, the standard of practice varies across the APAC region due to differences in culture, socioeconomic state and healthcare set-up. Practice may also differ from the rest of the world. Hence, a panel of experts was invited to discuss topics relevant to bifurcation intervention in order to make a concerted effort to achieve consensus that is applicable within the region and in line with available evidence.

Efficacy of coronary imaging on bifurcation intervention

During the coronary bifurcation intervention procedure, imaging including intravascular ultrasound and optical coherence tomography is essential to provide precise anatomy of the lesion and morphological information. This consensus document between the Korean Bifurcation Club and the Japanese Bifurcation Club summarizes practical guidelines and current evidences on lesion assessment, device selection, procedural guidance, and the optimization of bifurcation intervention by the imaging.

5-Year Outcomes According to FFR of Left Circumflex Coronary Artery After Left Main Crossover Stenting

OBJECTIVES

The aim of the current study was to evaluate the long-term clinical impact of fractional flow reserve (FFR) in jailed left circumflex coronary artery (LCx) after left main coronary artery (LM) simple crossover stenting.

BACKGROUND

Although the provisional side-branch intervention with FFR guidance has been validated for non-LM bifurcation lesions, the outcome of such a strategy in LM bifurcation disease is not well-known.

METHODS

Patients who underwent LM-to-left anterior descending coronary artery simple crossover stenting and who had FFR measurements in the LCx thereafter were enrolled. A low FFR was defined as ≤0.80. The clinical outcomes were assessed by the 5-year rate of target lesion failure (TLF) (a composite of cardiac death, target-vessel myocardial infarction, or target lesion revascularization).

RESULTS

In 83 patients, the mean FFR of the LCx after LM stenting was 0.87 ± 0.08, and 14 patients (16.9%) had a low FFR. There was no correlation between the FFR and angiographic % diameter stenosis in jailed LCx (R² = 0.039; p = 0.071) and there was no difference in the angiographic % diameter stenosis in the high and low FFR groups. At 5 years, the low FFR group had a significantly higher rate of TLF than the high FFR group (33.4% vs. 10.7%; hazard ratio: 4.09, 95% confidence interval: 1.15 to 14.52; p = 0.029). However, there was no difference in the clinical outcomes according to the angiographic % diameter stenosis. In a multivariate analysis, a low FFR was an independent predictor of the risk for a 5-year TLF (hazard ratio: 6.49; 95% confidence interval: 1.37 to 30.73; p = 0.018).

CONCLUSIONS

The patients with a high FFR in jailed LCx had better 5-year outcomes than those with a low FFR. The FFR measurement in jailed LCx can be helpful in selecting an adequate treatment strategy and may reduce unnecessary complex procedures.

A case of very late stent thrombosis on the protruded struts at the left main coronary bifurcation

A previous autopsy study has revealed that malapposed or protruded struts in the coronary bifurcation were a risk factor for very late stent thrombosis (VLST); however, a live clinical case has not yet been reported due to difficulty in observation at the VLST site. In this case, a 56-year-old male patient underwent a zotarolimus-eluting stent implantation in the proximal left anterior descending artery for acute myocardial infarction 3 years previously and had been treated with dual antiplatelet therapy. The patient experienced chest pain and suddenly collapsed due to acute coronary syndrome caused by a huge thrombus in the left main coronary bifurcation. After insertion of the intra-aortic balloon pump, kissing balloon inflation improved coronary flow and hemodynamics. Two weeks later, a 3-dimensional optical frequency domain imaging (3-D OFDI) revealed uncovered protruded struts on the ostium of the left circumflex artery (LCX). We removed the protruded struts using a double lumen catheter, for which the second wire was advanced to more distal cell along with the first wire located in the same LCX branch. 3-D OFDI clearly demonstrated that uncovered protruded struts at the LCX ostium were the cause of VLST and navigated optimal wiring with a double lumen catheter. Learning objective: Existence of protruded struts at the coronary bifurcated branch ostium is a risk factor for very late stent thrombosis. Three-dimensional optical frequency domain imaging clearly demonstrates the protruded strut configuration at the side branch of ostium and facilitates optimal guide wire re-crossing for kissing balloon inflation. Usage of double lumen catheter increases the possibility of optimal side branch wiring.

Szabo 2-stent technique for coronary bifurcation lesions: procedural and short-term outcomes

BACKGROUND

Provisional 1-stent technique is currently regarded as the default approach for the majority of bifurcation lesions. Nonetheless, 2-stent techniques may be required for complex bifurcations with high compromise risk or fatal consequences of side branch (SB) occlusion. Limitations exist in current approaches, as stents gap, multiple metal layers and stent malapposition caused by imprecise placement with fluoroscopic guide and intrinsic technical defects. This study was designed to investigate the effectiveness of the novel Szabo 2-stent technique for coronary bifurcation lesions.

METHODS

In the Szabo 2-stent technique, one stent is precisely implanted at the SB ostium with Szabo technique resulting in a single strut protruding into the main vessel (MV). After MV rewiring and SB guidewire withdrawal, another stent is implanted in MV followed by proximal optimization technique, SB rewiring, and final kissing inflation (FKI).

RESULTS

The technique tested successfully in silicone tubes (n = 9) with: procedure duration, 31.2 ± 6.8 min; MV and SB rewiring time, 26.8 ± 11.2 s and 33.3 ± 15 s; easy FKI; and 2.3 ± 0.5 balloons/procedure. Bifurcation lesions (n = 22) were treated with angiographic success in MV and SB, respectively: increased minimal lumen diameter (0.63 ± 0.32 mm to 3.20 ± 0.35 mm; 0.49 ± 0.37 mm to 2.67 ± 0.25 mm); low residual stenosis (12.4 ± 2.4%; 12.4 ± 2.3%); and intravascular ultrasound confirmed (n = 19) full coverage; minimal overlap and malapposition; minimal lumen area (2.4 ± 1.2 mm²; 2.1 ± 1.0 mm²); plaque burden (78.1 ± 11.3%; 71.6 ± 15.5%); and minimal stent area (9.1 ± 1.6 mm²; 6.1 ± 1.3 mm²). Periprocedural cardiac troponin increased in 1 asymptomatic patient without electrocardiographic change. There was no target lesion failure (cardiac death, myocardial infarction, target lesion revascularization) at 6-month follow-up.

CONCLUSIONS

The Szabo 2-stent technique for bifurcation lesions provided acceptable safety and efficacy at short-term follow-up.

Computational Simulations of Provisional Stenting of a Diseased Coronary Artery Bifurcation Model

Although stenting of non-branched arterial segments has acceptable clinical outcomes, in-stent restenosis (ISR) and stent thrombosis remain clinically significant issues for vascular bifurcations (15-28% restenosis). Local fluid and solid stresses appear to play an important role in restenosis and thrombosis. The combined role of wall shear stress (WSS) and circumferential wall stresses (CWS) is unclear in the case of stenting at vascular bifurcations. Using numerical simulations, we computed the fluid shear, solid stresses and the stress ratio at the the bifurcation region. Stenting of main vessel increased the maximum CWS in the the side branch (SB), resulting in a nearly two-fold increase of stress ratio in the SB compared to the MB (5.1 × 10⁵ vs. 9.2 × 10⁵). The existence of plaque decreased WSS and increased CWS near the carina, increasing the stress ratio at the SB. The changes of stress ratio were highly consistent with clinical data on bifurcation stenting. Fluid dynamics and solids mechanics should be considered in planning of stenting for a specific bifurcation, as their combined biomechanical effect may play an important role in stent restenosis and thrombosis.

Toward a sequential provisional coronary bifurcation stenting technique. From kissing balloon to re-POT sequence

The specific anatomy of coronary bifurcations makes them prime sites of atherogenesis and complicates revascularization. Account must be taken of the systematic difference in diameter between the 3 constituent vessels so as to minimize final side-branch ostium obstruction and maintain the law of conservation of flow, while respecting the bifurcation angles. Kissing balloon inflation (KBI) was long recommended, but never clearly demonstrated clinical benefit in single-stent provisional stenting. The detrimental proximal overstretch induced by simultaneous inflation of balloons, observed clinically and confirmed experimentally, probably explains this inefficacy. Advances in knowledge of bifurcation pathophysiology and experimental bench studies gradually led to the development of a new purely sequential technique, re-POT, without balloon juxtaposition, comprising 3 successive steps: (1) initial "proximal optimization technique" (POT), (2) side-branch opening, and (3) final POT. In contrast to KBI, re-POT has been progressively assessed from bench to first clinical study. The aim of the present review is to present the pathophysiological specificities of coronary bifurcations, and some explanations for the failure of KBI which led to the development of a new purely sequential coronary bifurcation provisional stenting strategy, based on re-POT.

Cardiovascular outcomes associated with crush versus provisional stenting techniques for bifurcation lesions: a systematic review and meta-analysis

Background

Percutaneous coronary intervention (PCI) for bifurcation lesions has often been challenging for Interventionists. Application of the correct intra-procedural technique is vital to generate beneficial outcomes after PCI. We aimed to systematically compare the post interventional cardiovascular outcomes which were reported using crush versus provisional stenting techniques for bifurcation lesions.

Methods

A computerized search was carried out through Medical Literature Analysis and Retrieval System Online, EMBASE, the Cochrane Central and through www.ClinicalTrials.gov for English publications comparing crush versus the provisional stenting techniques for coronary bifurcation lesions during PCI. Major adverse cardiac events, all-cause mortality, cardiac death, myocardial infarction, stent thrombosis, target vessel and target lesion revascularizations were the endpoints in this analysis. Odds ratios (OR) and 95% confidence intervals (CI) were generated during statistical analysis to represent the data.

Results

Six studies consisting of a total number of 2220 participants (1085 participants were assigned to the crush stenting technique and 1135 participants were assigned to the provisional stenting technique) enrolled between years 2004 and 2016 were included in this analysis.

During a follow-up time period from six to sixty months, major adverse cardiac events (OR: 0.73, 95% CI: 0.59–0.91; P = 0.005), target vessel revascularization (OR: 0.62, 95% CI: 0.43–0.89; P = 0.01) and target lesion revascularization (OR: 0.62, 95% CI: 0.45–0.85; P = 0.003) were significantly lower in patients who were assigned to the crush stenting technique. However, all-cause mortality (OR: 0.90, 95% CI: 0.48–1.68; P = 0.74), cardiac death (OR: 0.56, 95% CI: 0.29–1.08; P = 0.08), myocardial infarction (OR: 0.89, 95% CI: 0.62–1.27; P = 0.53) and stent thrombosis (OR: 0.72, 95% CI: 0.36–1.42; P = 0.34) were not significantly different.

Conclusion

In patients with coronary bifurcation lesions undergoing PCI, crush stenting technique was associated with significantly lower major adverse cardiac events and repeated revascularization without any change in mortality, myocardial infarction and stent thrombosis when compared to the provisional technique showing a benefit of crush over the provisional stenting technique during PCI.

Efficacy of the proximal optimization technique on crossover stenting in coronary bifurcation lesions in the 3D-OCT bifurcation registry

AIM

We sought to investigate the efficacy of the proximal optimization technique (POT) on crossover stenting followed by side branch (SB) dilation under optical coherence tomography guidance in a multicenter registry study.

METHODS AND RESULTS

A total of 135 bifurcation lesions in 134 patients were divided into POT (n = 52) and non-POT groups (n = 83). The POT was performed before SB dilatation (pre-POT; n = 26), finally (final-POT; n = 12), at both timing (re-POT; n = 13), and uncertain (n = 1). There were no significant intergroup differences in the success rate of guide wire re-crossing (GWR) into the optimal cell (72% vs. 65%), incidence of the link-free type in the configuration of the SB jailed struts (51% vs. 49%), or incomplete strut apposition at the bifurcation (13 ± 11% vs. 10 ± 9%). However, insufficient stent expansion close to the carina in the proximal main vessel (MV) due to inappropriate POT was likely to induce greater incomplete strut apposition (ISA) around the bifurcation. Only re-POT provided more symmetric proximal MV expansion, while pre- and final-POT did not.

CONCLUSION

The POT did not provide the expected beneficial effects, such as reduction of ISA or more optimal GWR, under the OCT guidance. Wide stent expansion in the proximal MV induced by the POT increased the likelihood of achieving optimal GWR, whereas symmetric stent expansion was provided by re-POT.

Development and validation of a risk scoring system based on baseline angiographic results by visual estimation for risk prEdiction of side-branch OccLusion in coronary bifurcation InterVEntion: The baseline V-RESOLVE score

OBJECTIVE

We aimed to adapt the visual estimation for Risk prEdiction of side-branch OccLusion in coronary bifurcation interVEntion (V-RESOLVE) score to enable risk prediction for side-branch (SB) occlusion using only baseline coronary angiogram data.

BACKGROUND

The V-RESOLVE score, which comprises angiographic factors at baseline and after lesion preparation, is a validated tool for predicting SB occlusion risk in coronary bifurcation intervention.

METHODS

To develop and validate the new scoring system, we used data pertaining to 1,545 patients and another 1,286 consecutive patients. Baseline V-RESOLVE was derived from V-RESOLVE by replacing the two pre-stenting angiographic factors with the corresponding preprocedural characteristics, while maintaining the scoring standard itself. We evaluated the diagnostic performance of baseline V-RESOLVE for predicting SB occlusion and preformed risk stratification with characterization of non-high-risk and high-risk lesions.

RESULTS

The area under the receiver operating characteristic curves was similar between baseline V-RESOLVE and V-RESOLVE (0.735 vs 0.756, P = 0.191), with good calibration for baseline V-RESOLVE (Hosmer-Lemeshow P = 0.714). Upon categorization by the baseline V-RESOLVE score, high-risk lesions (score: 14-43) demonstrated significantly higher rate of SB occlusion than did non-high-risk lesions (score: 0-13) (17.31% vs 4.74%, P < 0.01). Considering the V-RESOLVE-based risk stratification as reference, baseline V-RESOLVE had an integrated discrimination index of -1.81% (P = 0.052), and net reclassification improvement of -3.34% (P = 0.509). Upon validation, baseline V-RESOLVE provided satisfactory diagnostic performance and risk stratification.

CONCLUSIONS

Baseline V-RESOLVE predicts SB occlusion in coronary bifurcation intervention based solely on the preprocedural angiographic results.

Long-Term Follow-Up After Treatment of Drug-Eluting Stent Restenosis and De Novo Lesions Using SeQuent Please Paclitaxel-Coated Balloons

Managing patients with in-stent restenosis (ISR) remains an important clinical challenge. In particular, large, randomized trials assessing the effect of drug-eluting balloons (DEB) in patients with de novo lesions are warranted. We investigated the effect of DEB on procedural complications, target lesion revascularization (TLR), and major adverse cardiac and cerebrovascular events in patients with drug-eluting stent ISR and de novo lesions. The clinical profiles of 238 consecutive patients treated for coronary ISR (n = 174) and de novo lesions (n = 64) using SeQuent Please paclitaxel-coated balloon were analyzed. Study end points were major adverse cardiac events (MACEs). At 1-year follow-up, TLR and MACEs occurred with acceptably low rates (5.0% and 6.3%, respectively). At 2.00 (0.74) years of follow-up, there was a significant difference in the rates of TLR between the ISR and the de novo lesions groups (14.4% [ISR] vs 3.1% [de novo], P = .028), and the occurrence of MACEs distinctly increased in the ISR group compared to the de novo lesions group (21.8% vs 6.2%, P = .009). The long-term outcomes of the ISR group were inferior to those of the de novo group (TLR, log-rank P = .019; MACEs, log-rank P = .010). Drug-eluting balloon for ISR and de novo lesions of small coronary vessels is effective and safe.

Application of the MADS classification system in a "mega mammoth" stent trial: Feasibility and preliminary clinical implications

OBJECTIVES AND BACKGROUND

We attempted to test the feasibility of application of the MADS classification system in the largest stent trial to date and evaluate the preliminary clinical implications of this approach.

METHODS

In the randomized GLOBAL LEADERS trial, testing two different antiplatelet strategies in patients undergoing PCI with bivalirudin and biolimus-eluting stents, the e-CRF was dedicated to bifurcation treatment according to the MADS classification. Based on this e-CRF, the techniques used for bifurcations treatment in GLOBAL LEADERS were described and compared with two large, all-comer registries of bifurcations treatment (I-BIGIS and COBIS), used as historical controls.

RESULTS

Among 15,991 patients enrolled in the trial, 22,921 lesions treated at the index and staged procedure were available for analysis and 2,757 of these lesions were bifurcations and 7 were trifurcation lesions. The e-CRF-based MADS classification was achieved in 2,757 of these lesions (100%). 80.3% of bifurcations were treated using a single stent, 18.9% using 2 stents and 0.7% using 3 stents. Overall, the "main across side first" approach (A) was used in 77.4% with the "side branch first" approach (S) being the second most frequently used technique (10.2%). A single stent was used in the majority of the "A" approach (87.9%). A reduction in the use of 2-stent techniques (from 33.9 to 18.9%) was observed between GLOBAL LEADERS and I-BIGIS. The "A" approach was the most frequently used technique in GLOBAL LEADERS, while in COBIS the "S" strategy was most frequently employed.

CONCLUSIONS

Application of the MADS classification through an e-CRF was feasible in the largest stent trial today and provided useful information about the trends observed overtime in the treatment of bifurcation lesions.

The modified balloon crush technique: A simplified approach to optimizing final kissing balloon inflation

This study aimed to investigate the feasibility and safety of the modified balloon crush technique.The conventional crush technique accompanies difficult and suboptimal final kissing balloon inflation (FKI)In a single-center percutaneous coronary intervention registry, 515 patients with 515 bifurcation lesions were treated with the modified balloon technique (n = 70) or the conventional crush technique (n = 445). In contrast to the conventional crush technique, where the implanted side branch (SB) stent is crushed by expansion of the main branch (MB) stent, the modified balloon crush technique uses balloon crushing and additional SB ballooning across the crushed SB stent before MB stenting to facilitate FKI. The primary outcome of interest was major adverse cardiovascular event (MACE), a composite of all-cause death, spontaneous myocardial infarction, and target vessel revascularization.Baseline clinical and angiographic characteristics were similar between the 2 treatment groups. FKI had comparable success rates in both groups (97.1% for the modified balloon group and 98.4% for the conventional crush group; P = .35). There were no differences in procedure time, fluoroscopic time, or contrast amount between the 2 groups. At 1-year follow up, the cumulative MACE incidences were comparable between the 2 groups (7.3% vs 8.8%; P = .73). The incidence of target lesion revascularization (TLR) was significantly lower after the modified balloon crush technique compared with the conventional crush technique (0% vs 5.6%; P = .048).The modified balloon crush technique appears to be a feasible and safe alternative to the conventional crush technique with the potential to reduce the revascularization rate.

Should kissing balloon inflation after main vessel stenting be routine in the one-stent approach? A systematic review and meta-analysis of randomized trials

The KBI (kissing balloon inflation) technique is considered the default strategy for the two-stent approach in real world practice. Studies comparing KBI and No-KBI in patients undergoing the one-stent approach have reported conflicting results. The meta-analysis was performed to compare the clinical outcomes of the KBI strategy and the No-KBI strategy for coronary bifurcation lesions in the one-stent approach. Five randomized studies were included, and a total of 1264 patients were involved in the meta-analysis. The primary outcome was cardiac death. The secondary end points were stent thrombosis, MI (myocardial infarction), target lesion revascularization (TLR), target vessel revascularization (TVR), and main vessel and side branch restenosis. Compared with the No-KBI strategy, the KBI strategy was associated with a significant reduction in side branch restenosis (OR: 0.44, 95% CI: 0.30–0.64, p<0.001). A high risk of main vessel restenosis was found in the KBI group (OR: 2.96, 95% CI: 1.74–5.01, p<0.001). There were no significant differences in rates of cardiac death (OR: 1.89, 95% CI: 0.60–5.95, p = 0.28), stent thrombosis (OR: 0.98, 95% CI: 0.19–4.94, p = 0.98), MI (OR: 0.68, 95% CI: 0.33–1.44, p = 0.30), TLR (OR 1.14, 95% CI 0.68–1.90, p = 0.62), or TVR (OR 1.27, 95% CI 0.75–2.16, p = 0.38). Compared with the No-KBI strategy, the KBI strategy reduced the incidence of side branch restenosis and increased the risk of main branch restenosis in the one-stent approach. However, the clinical outcomes were similar between the KBI and No-KBI groups.

Single- Versus 2-Stent Strategies for Coronary Bifurcation Lesions: A Systematic Review and Meta-Analysis of Randomized Trials With Long-Term Follow-up

Background

The majority of coronary bifurcation lesions are treated with a provisional single‐stent strategy rather than an up‐front 2‐stent strategy. This approach is supported by multiple randomized controlled clinical trials with short‐ to medium‐term follow‐up; however, long‐term follow‐up data is evolving from many data sets.

Methods and Results

Meta‐analysis of randomized controlled trials evaluating long‐term outcomes (≥1 year) according to treatment strategy for coronary bifurcation lesions. Nine randomized controlled trials with 3265 patients reported long‐term clinical outcomes at mean weighted follow‐up of 3.1±1.8 years. Provisional single stenting was associated with lower all‐cause mortality (2.94% versus 4.23%; risk ratio: 0.69; 95% confidence interval, 0.48–1.00; P=0.049; I²=0). There was no difference in major adverse cardiac events (15.8% versus 15.4%; P=0.79), myocardial infarction (4.8% versus 5.5%; P=0.51), target lesion revascularization (9.3% versus 7.6%; P=0.19), or stent thrombosis (1.8% versus 1.6%; P=0.28) between the groups. Prespecified sensitivity analysis of long‐term mortality at a mean of 4.7 years of follow‐up showed that the provisional single‐stent strategy was associated with reduced all‐cause mortality (3.9% versus 6.2%; risk ratio: 0.63; 95% confidence interval, 0.42–0.97; P=0.036; I²=0).

Conclusions

Coronary bifurcation percutaneous coronary intervention using a provisional single‐stent strategy is associated with a reduction in all‐cause mortality at long‐term follow‐up.

Prognostic impact of final kissing balloon technique after crossover stenting for the left main coronary artery: from the AOI-LMCA registry

It is still uncertain whether the final kissing balloon technique (FKBT) is mandatory after crossover stenting for the left main coronary artery (LMCA). Assessing Optimal Percutaneous Coronary Intervention for LMCA (AOI-LMCA) registry, a 6-center retrospective registry, enrolled 1809 consecutive patients for LMCA stenting in Japan. In the present analysis, 5-year clinical outcomes were compared between non-FKBT (n = 160) and FKBT (n = 578) groups in patients treated with crossover stenting with drug-eluting stents from the LMCA to the left anterior descending artery. Propensity score-matched analysis was also performed in 160 patient pairs. In the entire study population as well as in the propensity-matched population, the cumulative 5-year incidence of the primary outcome measure (target lesion revascularization: TLR) was not significantly different between the FKBT and non-FKBT groups (10.7 versus 14.3%, P = 0.49, and 11.8 versus 14.3%, P = 0.53, respectively). In the sensitivity analysis by the multivariable Cox proportional hazard model, the effect of FKBT relative to non-FKBT for TLR remained insignificant (adjusted HR 0.89, 95% CI 0.47–1.69, P = 0.72). Regarding the TLR location, there were no significant differences in the cumulative incidences of TLR for LMCA-only, for the main branch, and for the side branch between the 2 groups (2.2 versus 1.3%, P = 0.93, 11.8 versus 9.1%, P = 0.71, and 8.2 versus 7.6%, P = 0.82, respectively). FKBT after a 1-stent strategy for LMCA crossover stenting did not affect TLR and other clinical outcomes during 5-year follow-up.

Clinical Trial Registration: Assessing Optimal Percutaneous Coronary Intervention for Left Main Coronary Artery Stenting Registry (AOI LMCA Stenting Registry). http://www.umin.ac.jp/ctr/index/htm/. Unique Identifier: UMIN000014706.

Bench testing and coronary artery bifurcations: a consensus document from the European Bifurcation Club

This is a consensus document from the European Bifurcation Club concerning bench testing in coronary artery bifurcations. It is intended to provide guidelines for bench assessment of stents and other strategies in coronary bifurcation treatment where the United States Food and Drug Administration (FDA) or International Organization for Standardization (ISO) guidelines are limited or absent. These recommendations provide guidelines rather than a step-by-step manual. We provide data on the anatomy of bifurcations and elastic response of coronary arteries to aid model construction. We discuss testing apparatus, bench testing endpoints and bifurcation nomenclature.