Stenting strategy for coronary artery bifurcation with drug-eluting stents: a meta-analysis of nine randomised trials and systematic review

Comparison of Provisional 1-Stent Strategy With Drug-Eluting Balloon Versus Planned 2-Stent Strategy in Patients With Non-LM Coronary True-Bifurcation Lesions (PROVISION-DEB)

Percutaneous coronary intervention (PCI) for bifurcation lesions presents several difficulties and often results in suboptimal procedural, postprocedural clinical outcomes. While the provisional 1-stent strategy is generally favored for its simplicity and favorable outcomes, a few studies suggest no significant difference between 1-stent and 2-stent techniques for true bifurcation lesions. Drug-eluting balloons (DEBs) have demonstrated potential in small vessel disease, including bifurcation side branches. However, no studies have compared the 2-stent strategy with the provisional 1-stent plus DEB strategy in non-LM true bifurcation lesions. Our study aims to address this gap by comparing these strategies, with a focus on real-world practice and detailed endpoint analysis. The PROVISION-DEB study is an open-label, randomized, multicenter clinical trial designed to investigate noninferiority and compare a 1-stent strategy with a drug-eluting balloon and a planned 2-stent strategy at non-LM coronary true-bifurcation lesions. A total of 750 patients with de novo non-LM coronary bifurcation lesions undergoing coronary interventions will be randomized 1:1 to either a provisional 1-stent plus DEB strategy or a 2-stent strategy with stratified Diabetes. The primary endpoint is a target lesion failure, composite outcome of cardiac death, target vessel myocardial infarction, or target lesion revascularization at the anticipated 3 years follow-up (6, 12, and 36 months). In conclusion, PROVISION-DEB study is a randomized, multicenter, noninferior clinical trial and will compare a 1-setnt strategy with a drug-eluting balloon and a planned 2-stent strategy at non-LM coronary true-bifurcation.

Immediate, Short-Term, Intermediate, and Long-Term Clinical Outcomes of True Bifurcation Stenting

INTRODUCTION

Coronary artery bifurcation lesion is an epicardial stenosis that, when compared to non-bifurcation lesions, poses a greater risk of adverse events and can compromise prognosis. This study aims to investigate the clinical efficacy of different stenting techniques, particularly in terms of their immediate, short-term, intermediate, and long-term outcomes in patients with true bifurcation lesions.

METHODOLOGY

This retrospective observational cohort study was conducted in a tertiary cardiac hospital in Islamabad, from February 1, 2015, to February 28, 2021. A total of 172 patients who met the inclusion criteria and underwent percutaneous coronary intervention were selected using a consecutive sampling technique. Follow-up was maintained for three years to assess procedural outcomes.

RESULTS

Of the 172 participants, the majority were males (69%) and only 4% were above 75 years of age. A significant relation between major adverse cardiac events (MACEs) with acute coronary syndrome (ACS) and previous percutaneous coronary intervention (PCI) (p < 0.000) was observed. Procedural success was good in all patients using the drug-eluting stent. The MAC rate was 6.9% and the final kissing balloon inflation, stenting technique, and bifurcation involvement were significantly associated with MACE occurrence (p < 0.01), and mortality was reported in two patients (1.16%). MACEs were associated with mortality; previous PCI and hypertension increased the risk of mortality.

CONCLUSION

The two-stent strategy can be used with good long-term outcomes and low complication rates.

Early effect of different bifurcation techniques on left ventricular mechanics in elective percutaneous coronary intervention

BACKGROUND

Bifurcation lesions are prevalent amongst patients with symptomatic coronary artery disease subjected to percutaneous coronary intervention (PCI). Recent consensus commends a conservative (provisional) approach when managing the side branch. Here, the aim was to explore the immediate impact of different bifurcation techniques (one stent and two stent strategies) on left ventricular LV) myocardial functions using speckle tracking echocardiography in patients subjected to elective PCI. Sixty two consecutive patients diagnosed with coronary bifurcation lesion (CBL) were enrolled. Patients were categorized into: one-stent strategy (Provisional group, n = 44) and a two-stent strategy (TAP, DK crush, or Culotte technique, n = 18), based on the coronary bifurcation site, angle, side branch diameter and Medina classification. LVEF%, regional and global longitudinal strain (GLS), and E/E' were measured before and within 24 h post PCI.

RESULTS

In both provisional and 2- stent technique, the mitral inflow velocities and mitral annular velocities showed improvement with significant reduction in E/e' (P < 0.03 and P < 0.001) respectively while LVEF% did not change. There were no significant changes in any other echo parameters post PCI. In provisional group, there were significant improvements in LAD (P < 0.001), RCA (P < 0.01) territories and GLS (P < 0.01). Δ LAD was expressively higher (34.5%) compared with Δ LCX (9.6%) and ΔRCA (25.4%), P < 0.001, P < 0.01 respectively. In the 2-stent technique group, there were significant improvements in peak longitudinal strain of LAD territory (P < 0.01), RCA territory (P < 0.01) and GLS (P < 0.01) respectively. Δ LAD territory was significantly higher in provisional group in comparison with the 2- stent technique group. Δ GLS was correlated inversely to Gensini score in provisional group and to the number of vessel diseased in 2-stent technique group.

CONCLUSION

PCI of the bifurcation lesion positively impact myocardial function. Both bifurcation techniques improve LV mechanical properties using 2D strain imaging while LV EF% remains unchanged.

Outcomes of Provisional Stenting With Versus Without Side Branch Intervention in Patients With Bifurcation Lesion-Related ST-Segment Elevation Myocardial Infarction

To date, the best approach to coronary bifurcation lesion remains unsettled, and the parameters to guide side branch ballooning or stenting are not yet defined. This study aimed to compare the survival outcomes after provisional stenting with versus without side branch intervention. A cohort was conducted on 132 patients who underwent coronary angiography at Toulouse University Hospital for ST-segment elevation myocardial infarction with large culprit nonleft main coronary bifurcation lesion. Study participants were divided into 2 groups depending on the performance or not of a side branch intervention. We observed the living status at 1-year after hospital discharge. Side branch intervention by balloon inflation or final balloon kissing technique was performed in 34.1% of study participants. At 1-year follow-up, the incidence of all-cause mortality was 7.8 per 100 person-years (95% confidence interval [CI] 4.1 to 15), and although it seemed higher in the side branch intervention group (10 per 100 person-years [95% CI 3.8 to 26.7] vs 6.6 per 100 persons-years [95% CI 2.8 to 15.9]), the survival analyses showed no differences in survival outcomes (hazard ratio side branch intervention 1.55 [0.42 to 5.78], p = 0.513). In conclusion, in the setting of a coronary bifurcation causing ST-segment elevation myocardial infarction, simple provisional stenting without side branch intervention showed a low mortality rate and no differences in the 1-year survival outcomes.

A novel hybrid strategy of drug coated balloon and stent for coronary bifurcation lesions

Background. Provisional side branch (SB) stenting strategy is the default approach for the majority of bifurcation lesions, but outcomes of SB is suboptimal. Though drug coated balloon (DCB) improving SB outcomes attracts an increasing attention, sequence of DCB hasn't yet been determined. We presented a novel hybrid strategy of DCB and stent for bifurcation lesions. Methods. With lesion preparation, DCB was persistently inflated in SB kissing with main branch (MB) stent deployment and balloon post-dilation of the bifurcation core. Proximal optimization technique was performed strictly not exceeding the bifurcation. Procedural and clinical adverse events were evaluated. Canadian Cardiovascular Society (CCS) angina classification was assessed at baseline and clinical follow-up. Results. Fourteen patients undergoing the hybrid technique from August 2020 to July 2021 were enrolled. The technique was successfully performed in all patients without rewiring or SB compromise. Minimal lumen diameter of SB increased from 0.60 ± 0.40 mm to 2.1 ± 0.2 mm while the percent stenosis decreased from 72.4 ± 17.9% to 19.6 ± 4.7%. In addition, intravascular ultrasound indicated comparable stent symmetry index and incomplete stent apposition between proximal and distal segments of stent. No further intervention was performed, and mean fractional flow reserve of SB (n = 12) was 0.88 ± 0.05. No major adverse cardiac events was noted in hospital and 12-month follow up. The mean CCS angina score was reduced by 84% (2.2 vs 0.4, p < .001). Conclusion. The hybrid strategy facilitates treatment of DCB and stent for bifurcation lesions, which appears to be feasible and acceptable in a short-term follow-up.

An observational study assessing the use of Sirolimus-eluting balloons for side-branch treatment in the provisional stenting of coronary bifurcations

Background

Drug eluting balloons (DEB) are a feasible method of rapid delivery of drug to a coronary vessel wall. Their efficacy has been established for the treatment of in-stent restenosis and small vessel disease but there is limited data for their use in bifurcation lesions.

Objective

The aim of this study was to assess the effectiveness of provisional upfront side-branch DEB use in bifurcation lesions compared to a simple balloon (POBA) or upfront 2 stent bifurcation strategy.

Methods

We conducted an observational study of 625 patients undergoing PCI to bifurcation lesions. All the patients had a DES deployed in the main vessel (MV). Decision on revascularization option for the side branch (SB) was made by the operator. The primary endpoint was target vessel failure. Secondary endpoints were target vessel myocardial infarction and all-cause mortality.

Results

311 patients had upfront DEB to the SB whilst the remaining were treated with either DES (188) or POBA (126). Baseline characteristics were similar aside from history of previous MI, which were higher in patients treated with DES or POBA, p = 0.009 whereas patients with previous CABG were likely to undergo DEB treatment (p = 0.004). TVF was more likely to occur in the POBA group (7.5 %) compared to the DEB (3.3 %) and DES (3.3 %) groups (p = 0.0019). There was no significant difference in TV-MI (p = 0.62) or death (p = 0.98) between the groups.

Conclusion

This study suggests that provisional bifurcation stenting with upfront Sirolimus DEB use in the SB is an effective treatment for non-LMS bifurcation PCI.

Reasons and frequency of transition to a double-stent technique when correcting bifurcation lesions of the coronary arteries in patients with acute coronary syndrome

The objective was to estimate the risk and predictors of intraoperative transition from a single-stent technique of correction of bifurcation lesions of the coronary arteries to a double-stent technique.

METHODS AND MATHERIALS. The study included 49 patients (35 men – 71.4 % and 14 women – 28.6 %) with acute coronary syndrome, whose coronary angiography revealed non-stem bifurcation lesions of the coronary arteries. The patients were operated with single- (Provisional) and double- (Culotte and TAR) stent techniques. Three patients had two bifurcation lesions at once. Thus, 52 bifurcations were included in the study. The average age of patients was 62±8 years. The lateral branch was affected in 34.6 % of cases. A blood clot in the bifurcation area was visualized in 15.4 % of cases. The study is a prospective analytical one. Statistical data processing was carried out using the chi-square test. The statistically significant value was considered p<0.05.

RESULTS. In Y-type bifurcation, kissing dilation was performed in 50% of cases, and stent implantation into the lateral branch - in 23.8% of cases (47.6% of cases where kissing dilation was performed). In T-type bifurcation, kissing dilation was required in 33.3% of cases, and the transition to double-stent technique was required in 11.1% of cases (33.3% of cases where kissing dilation was performed (p=0.610)). With the initially affected lateral branch, kissing dilation was required in 88.2 % of cases, and stenting of the lateral branch was required in 47.1 % of cases (53.3% of cases where kissing dilation was performed). With an intact lateral branch, kissing dilation was required in 26.5 % of cases, the second stent was needed in 8.8 % of cases (33.3% of cases where kissing dilation was performed (p<0.001)). In the presence of a blood clot in the bifurcation area, the need for kissing dilation appeared in 75% of cases, and the need for double-stent technique – in 12.5% of cases (20% of cases where kissing dilation was performed).

CONCLUSIONS. When using the Provisional techniques, the kissing dilation was required in 47.1 % of cases. Expansion of the scope of surgical intervention to double-stent technique was required in 21.6 % of cases.

Coronary Bifurcation Stenting: Review of Current Techniques and Evidence

BACKGROUND

Coronary bifurcation stenting constitutes 20% of all PCI performed. Given the extensive prevalence of bifurcation lesions, various techniques have sought to optimally stent the bifurcation to improve revascularization while also decreasing rates of stent thrombosis and lesion recurrence. Advanced techniques, such as planned two-stent approaches, have been shown to have improved outcomes but also require fluoroscopy and procedure time, posing an economic argument as well as a patient-outcome one.

OBJECTIVE

Because of the many strategies posited in the literature, it becomes essential to objectively evaluate evidence from randomized controlled trials and meta-analyses to help determine the optimal stenting strategy.

METHODS

We reviewed the clinical evidence on the efficacy of coronary bifurcation stenting.

RESULTS

In this paper, we review the most recent randomized controlled trials and meta-analyses on the efficacy of various stenting techniques and advances in stenting technologies published to gauge the current state of understanding and chart where the field is heading.

CONCLUSION

Bifurcation stenting is a maturing problem in the field of interventional cardiology that is adapting to the needs of the patients and advances in technology.

The importance of side branch preservation in the treatment of chronic total occlusions with bifurcation lesions

OBJECTIVES

The aim of this study was to identify the predictive factors for suboptimal result in side branch (SB) in chronic total occlusion (CTO) bifurcation lesions and clinical outcomes of patients with suboptimal result in SB.

BACKGROUND

There is little evidence on the optimal strategy for bifurcation lesions in CTO.

METHODS

We retrospectively reviewed 314 consecutive bifurcation lesions in CTO with SB ≥ 2.5 mm in 3 hospitals from March 2010 to June 2018. Patients were divided into the two groups based on the suboptimal SB treatment (SST) and optimal SB treatment (OST) groups. The baseline characteristics, procedural and clinical outcomes were compared between the two groups. This study also evaluated the predictors of suboptimal result in SB.

RESULTS

Suboptimal result in SB occurred in 47 cases. Presence of stenosis in SB, bifurcations located within the occluded segment and sub-intimal tracking at SB ostium was an independent predictor of suboptimal result in SB. The cumulative incidence of target lesion revascularization (TLR) in all lesions was not significantly different between the two groups, however, TLR in right coronary artery (RCA) was significantly higher in the SST group. In the Cox regression analysis, suboptimal result in SB in RCA and sub-intimal tracking were independent predictors of TLR for MB. In patients with bifurcations located within the occluded segment, usage of two-stent technique was significantly lower in the SST group.

CONCLUSIONS

Meticulous procedures are required for SB preservation to improve not only SB prognosis but also MB, especially in RCA.

Predictors and complications of side branch occlusion after recanalization of chronic total occlusions complicated with bifurcation lesions

Data on risk factors and periprocedural complications associated with side branch (SB) occlusion after chronic coronary total occlusion (CTO) recanalization are limited. The aims of this study were to identify independent predictors of side branch (SB) occlusion after chronic total occlusion (CTO) recanalization and assess the relationship between SB occlusion and perioperative complications. 245 patients with CTO bifurcation lesions (BFLs) who underwent successful CTO recanalization were included in the study. In the occlusion group, most of the SB occlusions were observed after the implantation of the stents and lack of SB protection was more common. However, there was no significant between-group difference in the angles between the main vessel (MV) and SB. SB occlusion was associated with a higher risk of periprocedural myocardial infarction and a higher composite periprocedural complication rate. Identified as predictors of SB occlusion were no SB protection, use of a dissection-reentry strategy, ostial SB stenosis, and proximal MV stenosis of 50% or more.

[Use of drug-coated balloons for interventions on bifurcation lesions of coronary arteries]

Interventions on bifurcation lesions of the coronary bed are one of the most complicated tasks of interventional cardiology. Recent trends are toward active study of using drug-eluting balloons for interventions in this type of lesions. Using such technique makes it possible to minimize the risks associated with implantation of stents in sites of coronary artery bifurcations with good angiographic results. This article is a review of the literature data concerning the use of drug-coated balloons in interventions on bifurcation lesions of the coronary bed, discussing peculiarities of the balloon catheter design, dynamics of delivery of an antiproliferative drug to the vascular wall. This is followed by considering the experience with using innovative sirolimus-coated balloon catheters, as well as future perspectives of these devices for interventions in coronary artery bifurcation lesions.

Coronary bifurcations treated with thin-strut drug-eluting stents: a prespecified analysis of the randomized BIO-RESORT trial

BACKGROUND

Treatment of a coronary bifurcation lesion is often required in routine clinical practice, but data on the performance of very thin-strut biodegradable polymer drug-eluting stents are scarce.

METHODS

Comparison of biodegradable polymer and durable polymer drug-eluting stents in an all comers population (BIO-RESORT) is a prospective, multicenter randomized clinical trial that included 3514 all-comer patients, who were randomized to very thin-strut biodegradable polymer-coated sirolimus- or everolimus-eluting stents, versus thin-strut durable polymer-coated zotarolimus-eluting stents. The approach of bifurcation stenting was left at the operator's discretion, and provisional stenting was generally preferred. This prespecified analysis assessed 3-year clinical outcome of all patients in whom treatment involved at least one bifurcation with a side-branch diameter ≥1.5 mm.

RESULTS

Of all BIO-RESORT trial participants, 1236 patients were treated in bifurcation lesions and analyzed. Single- and two-stent techniques were used in 85.8% and 14.2%, respectively. 'True' bifurcation lesions (main vessel and side-branch obstructed) were treated in 31.1%. Three-year follow-up was available in 1200/1236 (97.1%) patients. The main endpoint target vessel failure (composite of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization) occurred in sirolimus-eluting stents in 42/412 (10.3%) and in zotarolimus-eluting stents in 49/409 (12.1%) patients (P-logrank = 0.40). In everolimus-eluting stents, target vessel failure occurred in 40/415 (9.8%) patients (vs. zotarolimus-eluting stents: P-logrank = 0.26). There was no between-stent difference in individual components of target vessel failure. Findings were consistent in patients with single-vessel treatment and patients treated with a single-stent technique.

CONCLUSIONS

Three years after stenting all-comers with bifurcation lesions, clinical outcome was similar with the sirolimus-eluting and everolimus-eluting stents versus the zotarolimus-eluting stent.

Drug coated balloons and their role in bifurcation coronary angioplasty: appraisal of the current evidence and future directions

INTRODUCTION

Coronary Bifurcation lesions are technically more challenging and Bifurcation percutaneous coronary intervention (PCI) remains a challenge with unpredictable and sub-optimal clinical and angiographic results. Drug-Coated Balloons (DCB) are emerging devices in the field of coronary intervention with promising results that may overcome some of drug eluting stents limitations and may have potential advantages in complex bifurcation PCI.

AREAS COVERED

We have performed a re-appraisal about the issues with current bifurcation PCI techniques and the use of DCB in the treatment of Bifurcation lesions. Several studies performed utilizing DCB are described and critically appraised. Over the recent years, there have been tremendous developments in the DCB technology, lesion preparation, clinical experience, and clinical data during bifurcation PCI. The current review describes the advances in the DCB technology, pharmacokinetics, role of excipients, and optimization of the technique. Special emphasis in lesion preparation and potential pathway of using DCB in bifurcation PCI is proposed.

EXPERT OPINION

Although different proof of concept and pilot studies have shown promising results in treatment of bifurcation lesions with DCB, larger randomized trials and/or international consensus papers are required to enable worldwide translation of this idea to clinical practice.

Percutaneous management of coronary bifurcation lesions: current perspective

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Outcomes of the Tryton-dedicated bifurcation stent for the treatment of true coronary bifurcations: Individual-patient-data pooled analysis

OBJECTIVES

We aimed to evaluate the safety and efficacy of the dedicated Tryton side branch (SB) stent for the treatment of true bifurcations involving large SBs.

BACKGROUND

Bifurcation lesions are associated with lower procedural success and a higher risk of adverse cardiac events. Provisional stenting (PS) is currently the default approach for the treatment of bifurcation lesions. The Tryton stent is a dedicated bifurcation stent system for the treatment of true bifurcation lesions.

METHODS

We performed an individual-patient-data pooled post-hoc analysis of the Tryton Pivotal randomized controlled trial and post-approval Confirmatory Study. Only patients with true bifurcations involving a SB ≥ 2.25 mm in diameter were included. The primary endpoint was non-inferiority of Tryton compared with PS for target vessel failure (TVF) at 1 year.

RESULTS

Of the 411 patients meeting the criteria for enrolment, 287 patients were treated with the Tryton stent and 124 with PS. Procedural success was higher in the Tryton group (95.4 versus 82.3%, P < 0.0001). TVF at 1 year was 8.1% in the Tryton group and 9.7% in the PS group, meeting the pre-specified criteria for non-inferiority established for the randomized controlled trail (p_{non-inferiority} = 0.02). At 9-month angiographic follow-up, SB diameter stenosis was significantly lower in the Tryton group (29.3 ± 21.9 versus 41.1 ± 17.5, P = 0.0008) and in-segment binary restenosis (diameter stenosis ≥ 50%) was higher in the PS group (19.0 versus 34.2%, respectively, P = 0.052).

CONCLUSIONS

In patients with true bifurcations involving a large SB, treatment with the Tryton SD Stent was clinically non-inferior to PS and showed favorable angiographic outcomes.

Contemporary techniques in percutaneous coronary intervention for bifurcation lesions

INTRODUCTION

Treatment of coronary bifurcation lesions with contemporary state-of-the-art percutaneous coronary intervention (PCI) is still associated with higher rate of adverse cardiovascular events compared to non-bifurcation lesions. Bench testing and virtual computer modeling have increased our understanding of bifurcation PCI guiding refinement in bifurcation techniques. New insights on bifurcation PCI have the potential to further improve clinical outcomes in patients presenting with bifurcation lesions. Areas covered: The present manuscript aims to review the methods for bifurcation lesion assessment and treatment strategy step by step supported on bench and clinical evidence. Expert commentary: Invasive pressure-wire evaluation is essential to determine the appropriateness of bifurcation PCI, particularly in intermediate coronary stenosis. Treatment strategy relies on four parameters: diameters of the three segments of the bifurcation; lesion length and plaque distribution; and bifurcation angle. The optimal technique for bifurcation PCI is still debated, an individualized approach with an initial provisional side branch stenting strategy seems to be suitable in the 75 to 95% of patients. For more complex bifurcations, two-stent techniques may be required with increasing evidence supporting the usefulness of the double kissing balloon crush (DK-crush) technique.

The Tryton® dedicated bifurcation stent: Five-year clinical outcomes

AIMS

We report the first 5 year clinical follow-up data for the Tryton® bifurcation stent.

METHODS AND RESULTS

Clinical outcomes at five years were collected from 8 centres. Non-hierarchical Major Adverse Cardiovascular Events (MACE) and Major Adverse Cerebrovascular and Cardiovascular Events (MACCE) were collected. Diabetic and non-diabetic populations were compared, along with small (≤2.5 mm) vs large (>2.5 mm) side branch size. 173 patients with a follow up rate of 98% at 5 years were analysed. Non-hierarchical MACE was low at 9.8%, consisting of cardiac death of 1.2% (n = 2) and MI of 1.7% (n = 3). Target lesion revascularization (TLR) rate was 6.9% (n = 12). Non-hierarchical MACCE was also low, with major bleeding in 2.3% (n = 4) and strokes in 1.7% (n = 3) of patients. There was only 1 case (0.6%) of stent thrombosis that was definite and occurred very late (782 days). All-cause mortality was low, with 8.7% combined cardiac and non-cardiac death (n = 15). Diabetic patients had significantly higher event rates, but there was no difference in events with lesion stratification by side branch size.

CONCLUSIONS

The Tryton® Side-Branch Stent has a non-hierarchical MACE of 9.8% and MACCE of 13.9% at 5 years. The TLR was 6.9% with only 1 case of stent thrombosis recorded.

Fractional flow reserve (FFR) as a guide to treat coronary artery disease

INTRODUCTION

The presence and extent of myocardial ischemia are the major determinants of prognosis in patients with coronary artery disease (CAD). Unlike coronary angiography alone, fractional flow reserve (FFR) has enabled interventional cardiologists to accurately determine whether coronary atherosclerotic plaques are responsible for myocardial ischemia, and therefore deserve to be revascularized. Areas covered: An overview on the role of FFR in the diagnosis and treatment of coronary artery disease, as well as the potential related controversies is provided. Authors describe the coronary physiology underneath this technique and all the procedural aspects in the catheterization laboratory. The landmark trials and the current applications in different coronary lesions and syndromes are also described and potential future research involving FFR and comparisons with other methodologies for the evaluation of coronary physiology are introduced. Expert commentary: FFR is still unsurpassed in diagnostic performance when compared to non-hyperemic indices and noninvasive techniques, and remains the gold standard for the detection of ischemia-inducing coronary stenoses. FFR-guided PCI has been demonstrated superior to an angiography-guided PCI and over medical therapy alone, and ongoing investigation will clarify whether it could perform better, or at least equalize the results of cardiac surgery in patients with severe multivessel disease.

Benefit of a new provisional stenting strategy, the re-proximal optimisation technique: the rePOT clinical study

AIMS

A new coronary bifurcation provisional stenting technique without kissing balloon, rePOT, associating the proximal optimisation technique (POT), side branch inflation and final POT, showed excellent mechanical results in a bench test. The present study sought to use optical coherence tomography (OCT) to quantify the mechanical results of rePOT in vivo in a large patient sample with complex coronary bifurcations.

METHODS AND RESULTS

A total of 106 patients with coronary bifurcations were included in a multicentre prospective registry (left main, 40.6%; true Medina bifurcation, 39.6%). Three OCT runs were performed, at baseline, just after stent implantation and after the complete rePOT sequence, quantifying global malapposition, side branch obstruction (SBO), and various geometric arterial criteria. RePOT was completed systematically. RePOT significantly reduced global strut malapposition from 18.9±13.4% just after stent implantation to 3.2±3.9% (p<0.05), residual SBO from 44.3±12.9% to 17.0±14.3% (p<0.05), and ellipticity index from 1.19±0.11 to 1.13±0.12 (p<0.05). Exhaustive six-month follow-up found only one mother-vessel target lesion revascularisation.

CONCLUSIONS

This clinical study of a large sample of complex coronary bifurcations with OCT analysis showed the benefit of the rePOT sequence in provisional stenting, replicating in vivo the excellent in vitro geometric results previously reported, and confirming ease of implementation and medium-term safety.

Treatment effects of systematic two-stent and provisional stenting techniques in patients with complex coronary bifurcation lesions: rationale and design of a prospective, randomised and multicentre DEFINITION II trial

INTRODUCTION

Provisional stenting (PS) for simple coronary bifurcation lesions is the mainstay of treatment. A systematic two-stent approach is widely used for complex bifurcation lesions (CBLs). However, a randomised comparison of PS and two-stent techniques for CBLs has never been studied. Accordingly, the present study is designed to elucidate the benefits of two-stent treatment over PS in patients with CBLs.

METHODS AND ANALYSIS

This DEFINITION II study is a prospective, multinational, randomised, endpoint-driven trial to compare the benefits of the two-stent technique with PS for CBLs. A total of 660 patients with CBLs will be randomised in a 1:1 fashion to receive either PS or the two-stent technique. The primary endpoint is the rate of 12-month target lesion failure defined as the composite of cardiac death, target vessel myocardial infarction (MI) and clinically driven target lesion revascularisation. The major secondary endpoints include all causes of death, MI, target vessel revascularisation, in-stent restenosis, stroke and each individual component of the primary endpoints. The safety endpoint is the occurrence of definite or probable stent thrombosis.

ETHICS AND DISSEMINATION

The study protocol and informed consent have been approved by the Institutional Review Board of Nanjing First Hospital, and accepted by each participating centre. Written informed consent was obtained from all enrolled patients. Findings of the study will be published in a peer-reviewed journal and disseminated at conferences.

TRIAL REGISTRATION NUMBER

NCT02284750; Pre-results.

Novel bifurcation stents coated with bioabsorbable nanofibers with extended and controlled release of rosuvastatin and paclitaxel

A novel bifurcation stent coated with bioabsorbable nanofibers that deliver the extended and controlled release of rosuvastatin and paclitaxel was developed. Bioabsorbable bifurcation stents, consisting of a double-slit tubular main body and two spiral branches, were manufactured. Bi-layered poly (lactic-co-glycolic acid) nanofibers that contained rosuvastatin and paclitaxel were used for treating the stents. Various properties of the fabricated stents, including compression strengths, collapse pressure, water contact angle and flow properties within a circulation model, were quantified. In vitro nanofibrous elution chromatography assays from the drug-loading bifurcation stents were carried out for the release patterns of pharmaceuticals. The effectiveness of eluted rosuvastatin and paclitaxel in inhibiting the adhesion of platelets as well as the proliferation of smooth muscle cells (SMCs) were studied, respectively. The experimental results suggest that bioabsorbable nanofibrous bifurcation stents released high concentrations of rosuvastatin and paclitaxel for 27 and 70 days, respectively. The eluted drugs of rosuvastatin and paclitaxel effectively reduced adherent platelets and the proliferation of SMCs. The developed bioabsorbable nanofibrous bifurcation stents herein may provide a promising means of treating cardiovascular bifurcation lesions.

One Versus 2-stent Strategy for the Treatment of Bifurcation Lesions in the Context of a Coronary Chronic Total Occlusion. A Multicenter Registry

INTRODUCTION AND OBJECTIVES

There is little evidence on the optimal strategy for bifurcation lesions in the context of a coronary chronic total occlusion (CTO). This study compared the procedural and mid-term outcomes of patients with bifurcation lesions in CTO treated with provisional stenting vs 2-stent techniques in a multicenter registry.

METHODS

Between January 2012 and June 2016, 922 CTO were recanalized at the 4 participating centers. Of these, 238 (25.8%) with a bifurcation lesion (side branch ≥ 2mm located proximally, distally, or within the occluded segment) were treated by a simple approach (n=201) or complex strategy (n=37). Propensity score matching was performed to account for selection bias between the 2 groups. Major adverse cardiac events (MACE) consisted of a composite of cardiac death, myocardial infarction, and clinically-driven target lesion revascularization.

RESULTS

Angiographic and procedural success were similar in the simple and complex groups (94.5% vs 97.3%; P=.48 and 85.6% vs 81.1%; P=.49). However, contrast volume, radiation dose, and fluoroscopy time were lower with the simple approach. At follow-up (25 months), the MACE rate was 8% in the simple and 10.8% in the complex group (P=.58). There was a trend toward a lower MACE-free survival in the complex group (80.1% vs 69.8%; P=.08). After propensity analysis, there were no differences between the groups regarding immediate and follow-up results.

CONCLUSIONS

Bifurcation lesions in CTO can be approached similarly to regular bifurcation lesions, for which provisional stenting is considered the technique of choice. After propensity score matching, there were no differences in procedural or mid-term clinical outcomes between the simple and complex strategies.

Percutaneous coronary intervention of bifurcation lesions and platelet reactivity

BACKGROUND

Although bifurcation percutaneous coronary intervention (PCI) is associated with lower procedural success rates and higher risk of complications, there are little data regarding outcomes after successful bifurcation PCI with contemporary stents and techniques. Whether residual platelet reactivity (PR) affects outcomes differently after bifurcation versus non-bifurcation PCI is also unknown. We studied the association between bifurcation PCI, PR, and clinical outcomes among patients undergoing successful PCI with drug-eluting stents.

METHODS

Patients in the prospective, multicenter ADAPT-DES study were stratified according to whether they underwent bifurcation PCI. Two-year outcomes were compared between groups using Cox proportional hazards models. Target vessel failure (TVF) was defined as the composite of all-cause death, myocardial infarction, and ischemia-driven target vessel revascularization.

RESULTS

Among the 8582 patients included in ADAPT-DES, 1276 (15%) had bifurcation PCI. Bifurcation PCI was independently associated with increased risk of TVF (adjusted hazard ratio [HR] 1.26, 95% confidence interval [CI] 1.08-1.46, p=0.003), driven by higher risk of myocardial infarction (5.9% vs. 4.6%, p=0.033) and ischemia-driven target vessel revascularization (13.0% vs. 9.2%, p<0.0001). There was no statistical interaction between PR and bifurcation PCI regarding TVF risk (adjusted p_interaction=0.87). Stenting of both bifurcation branches was associated with the highest risk of TVF (adjusted HR 1.91, 95% CI 1.48-2.46 versus non-bifurcation PCI; p_trend<0.001).

CONCLUSIONS

Bifurcation PCI is associated with a higher risk of 2-year adverse ischemic events than non-bifurcation PCI, a risk that is particularly high when both bifurcation branches are stented, and with HPR conferring similar risk for bifurcation and non-bifurcation PCI.

Evaluation of coronary flow conditions in complex coronary artery bifurcations stenting using computational fluid dynamics: Impact of final proximal optimization technique on different double-stent techniques

BACKGROUND/PURPOSE

Computational fluid dynamics (CFD) have been recently adopted in many fields of cardiovascular medicine and in interventional cardiology. Using CFD analysis we compared the use of different PCI procedures, with and without the utilization of a proximal optimization technique (POT), on a complex coronary artery bifurcation.

METHODS/MATERIALS

For the analysis, we considered a hypothetic model of a left anterior descending artery-diagonal Medina 1,1,1 bifurcation type with a diameter of the proximal main branch (MB) and the side branch (SB) set at 3.5mm and 2.5mm, respectively. The bifurcation angle has been set to 50°. For the stent simulation, we reconstructed a third-generation, ultra-thin strut everolimus-eluting stent (ORSIRO stent, Biotronik IC, Bulack, Switzerland).

RESULTS

The Nano-crush and the modified T techniques seem able to restore the most physiologic fluid dynamic profile. Conversely, the DK-crush and the culotte demonstrated an intermediate and worst effect, respectively. The addition of a final POT resulted favorably for both Nano-crush and reverse modified T techniques, whereas a neutral and lack of significant effects have been observed for the DK-crush and culotte technique, respectively.

CONCLUSION

Different double-stenting techniques (DST) have a different impact on coronary flow physiology. Both Nano-crush and modified T techniques achieved the most physiologic profile. The addition of a final POT appears to be a favourable step for both Nano-crush and modified T.

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

BACKGROUND

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

METHODS AND RESULTS

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

Percutaneous Coronary Intervention for Bifurcation: How Can We Outperform the Provisional Strategy?

In the era of drug-eluting stents, the provisional stenting strategy has been established as the default strategy in percutaneous coronary intervention for bifurcation lesions. However, emerging evidence shows that, in selected situations, the complex strategy of stenting both vessels regardless could reduce side-branch restenosis without penalty. In particular, the double kissing crush technique has been proven to outperform the provisional strategy and other complex strategies in randomized trials. In this review, we present the evidence comparing the 2 strategies and individual stenting techniques and discuss the roles of other optimization techniques such as final kissing balloon inflation, proximal optimization technique, intravascular ultrasonography, and optical coherence tomography. Finally, we suggest a practical approach for choosing the optimal strategy for intervention with coronary bifurcation lesions.

Comparative Analysis of Sequential Proximal Optimizing Technique Versus Kissing Balloon Inflation Technique in Provisional Bifurcation Stenting: Fractal Coronary Bifurcation Bench Test

OBJECTIVES

This study used a fractal bifurcation bench model to compare 6 optimization sequences for coronary bifurcation provisional stenting, including 1 novel sequence without kissing balloon inflation (KBI), comprising initial proximal optimizing technique (POT) + side-branch inflation (SBI) + final POT, called "re-POT."

BACKGROUND

In provisional bifurcation stenting, KBI fails to improve the rate of major adverse cardiac events. Proximal geometric deformation increases the rate of in-stent restenosis and target lesion revascularization.

METHODS

A bifurcation bench model was used to compare KBI alone, KBI after POT, KBI with asymmetric inflation pressure after POT, and 2 sequences without KBI: initial POT plus SBI, and initial POT plus SBI with final POT (called "re-POT"). For each protocol, 5 stents were tested using 2 different drug-eluting stent designs: that is, a total of 60 tests.

RESULTS

Compared with the classic KBI-only sequence and those associating POT with modified KBI, the re-POT sequence gave significantly (p < 0.05) better geometric results: it reduced SB ostium stent-strut obstruction from 23.2 ± 6.0% to 5.6 ± 8.3%, provided perfect proximal stent apposition with almost perfect circularity (ellipticity index reduced from 1.23 ± 0.02 to 1.04 ± 0.01), reduced proximal area overstretch from 24.2 ± 7.6% to 8.0 ± 0.4%, and reduced global strut malapposition from 40 ± 6.2% to 2.6 ± 1.4%.

CONCLUSIONS

In comparison with 5 other techniques, the re-POT sequence significantly optimized the final result of provisional coronary bifurcation stenting, maintaining circular geometry while significantly reducing SB ostium strut obstruction and global strut malapposition. These experimental findings confirm that provisional stenting may be optimized more effectively without KBI using re-POT.

Percutaneous Coronary Intervention for Bifurcation Lesions

This article summarizes treatment alternatives for coronary bifurcation lesions. It also reviews current definitions and classifications pertaining to bifurcation lesions and provides an overview of the impact of bifurcation lesions on clinical outcomes.

Plaque morphology predictors of side branch occlusion after provisional stenting in coronary bifurcation lesion: Results of optical coherence tomography bifurcation study (ORBID)

OBJECTIVES

The aim of this study was to identify the predictors of side branch (SB) ostial stenosis developed after provisional stenting of the main vessel (MV) using optical coherence tomography (OCT).

BACKGROUND

Provisional stenting remains the main approach to treatment of bifurcation lesions; however, it may result in the narrowing of SB ostium. There is little information about underlying plaque morphology of the MV lesion and its potential impact on the SB after provisional stenting.

METHODS

Patients with stable coronary disease with angiographic MV lesion not involving SB were included in a prospective single center study. The primary outcome was significant SB ostium stenosis (SBOS), defined as residual stenosis of >50% after MV stenting.

RESULTS

Thirty bifurcation lesions in 30 patients were analyzed in the study. Poststenting significant SBOS was observed in 30% of patients. The MV lesions with SBOS > 50% were characterized by a higher prevalence of lipid rich plaques (100 vs. 64%, p = 0.040) and spotty calcifications (60 vs. 0%, p = 0.005). Maximal lipid arcs were greater (257° vs. 132°, p = 0.001) and lipid volume index was higher (1380 vs. 574, p = 0.012) in the SBOS >50% group. Multivariate logistic regression analysis identified maximal lipid arc (odds ratio (OR): 1.014, p = 0.038) and the presence of lipid plaque contralateral to SB ostium (OR: 8.14, p = 0.046) before stenting as independent predictors of significant SBOS after PCI.

CONCLUSIONS

High lipid content of the MV lesion and a contralateral location of lipid in the bifurcation area may contribute to SBOS after provisional stenting. © 2016 Wiley Periodicals, Inc.

Stenting of coronary bifurcation lesions: a literature and technical review

Newer generation drug-eluting stents have improved outcomes in various subsets of coronary lesions including bifurcation lesions. This article reviews the current literature on various issues in bifurcation percutaneous coronary intervention (PCI). Generally, the provisional approach of placing one stent in the main vessel is the preferred first-line treatment for most bifurcation lesions. However, some lesions require 2-stenting. It is unknown whether 2nd-generation DES have improved outcomes with 2-stenting. The use of fractional flow reserve (FFR) for the assessment of functional significance of the jailed side branch can help avoid unnecessary stenting in complex lesions. Skilled techniques in every step of the 2-stenting process and meticulous use of imaging techniques including IVUS or OCT are warranted to obtain optimal angiographic and clinical results. Dedicated bifurcation stents are feasible treatment options and may change future concepts in bifurcation PCI, although larger trials with control groups are required in order to widely apply these techniques into daily routine practice.

Impact of side branch stenting on five-year long-term clinical outcome with the bifurcation-dedicated Axxess Biolimus A9-eluting stent system

AIMS

Our aim was to evaluate the five-year clinical impact of side branch (SB) stenting with a drug-eluting stent (DES) following Axxess stent implantation in coronary bifurcation lesions.

METHODS AND RESULTS

Four hundred patients treated with Axxess were pooled from the AXXESS Plus and DIVERGE five-year follow-up studies. We compared unadjusted and propensity-adjusted major adverse clinical events (MACE) between Axxess with no SB stenting ("Axxess provisional") versus Axxess with SB stenting ("Axxess additional"). "Axxess additional" had no impact on the MACE rate, with unadjusted and adjusted HR 1.59 (95% CI: 0.95-2.64) and 1.37 (95% CI: 0.88-2.13), respectively. No differences were seen in the individual components of death, myocardial infarction and ischaemia-driven target lesion revascularisation, respectively, both in unadjusted (HR 0.92 [95% CI: 0.38-2.19]; HR 1.73 [95% CI: 0.78-3.82]; HR 1.65 [95% CI: 0.84-3.26]) and adjusted analysis (HR 0.92 [95% CI: 0.41-2.09]; HR 1.13 [95% CI: 0.59-2.17]; HR 1.31 [95% CI: 0.74-2.31]). No differences in definite stent thrombosis were seen with unadjusted HR 2.1 (95% CI: 0.45-9.88) and adjusted HR 1.0 (95% CI: 0.32-3.1).

CONCLUSIONS

Stenting the SB following Axxess implantation does not impact on long-term clinical outcomes compared to MV stenting only. The Axxess stent system offers a safe and tailored alternative for the treatment of coronary bifurcation lesions.