The impact of the extent of side branch disease on outcomes following bifurcation stenting

OBJECTIVES

To define the impact of side branch (SB) lesion length on clinical outcomes after percutaneous coronary intervention (PCI) on bifurcation lesions.

BACKGROUND

The role of the SB lesion length remains questionable in PCI planning and its implication on clinical outcome is controversial.

METHODS

Data from the retrospective multicenter EBC-P2BiTO registry were analyzed. The primary endpoint was the occurrence of major adverse cardiac events (MACE), defined as the composite of cardiac death, myocardial infarction excluding periprocedural, or stent thrombosis at 13 months median follow-up (IQR 11-28). By using propensity scores for inverse probability of treatment weighting (IPTW), the comparison of treatment groups was adjusted to correct for potential confounding.

RESULTS

Among 1,252 patients, SB was normal in 489 (39%), diseased in 763 (61%) cases. MACE occurred in 68 patients (5.4%). The optimal discriminant SB lesion length for MACE was ≥10 mm, with an area under the curve of 0.71 (p < .01). The incidence of MACE was higher among patients with SB lesions ≥10 mm (8%) than with normal SB (4.1%) (hazard ratio [HR], 2.8; 95% confidence interval [CI], 1.5-5.3; p = .001, IPTW-adjusted) or SB lesions <10 mm (5.1%) (HR, 1.5; 95% CI, 1.1-3.3; p = .048, IPTW-adjusted), being similar between these last two groups.

CONCLUSIONS

In bifurcation PCI, SB lesion length ≥ 10 mm identifies patients at higher risk of MACE than those with <10 mm SB lesions and those without SB disease, considering that no differences were observed among these last two groups. Careful planning is mandatory when approaching bifurcations with long SB lesions.

Impact of Kissing Balloon in Patients Treated With Ultrathin Stents for Left Main Lesions and Bifurcations

Background:

There are limited data regarding the impact of final kissing balloon (FKI) in patients treated with percutaneous coronary intervention using ultrathin stents in left main or bifurcations.

Methods:

All patients undergoing left main or bifurcations percutaneous coronary intervention enrolled in the RAIN registry (Very Thin Stents for Patients With MAIN or BiF in Real Life: The RAIN, a Multicenter Study) evaluating ultrathin stents were included. Major adverse cardiac event (a composite of all-cause death, myocardial infarction, target lesion revascularization, and stent thrombosis) was the primary end point, while its components, along with target vessel revascularization, were the secondary end points. The main analysis was performed comparing patients with and without FKI after adjustment with inverse probability of treatment weighting. Subgroup analyses were performed according to FKI (short [<3 mm] versus long overlap), strategy (provisional versus 2-stent), routine versus bail-out FKI, and the use of imaging and proximal optimization technique.

Results:

Two thousand seven hundred forty-two patients were included. At 16 months (8–20) follow-up, inverse probability of treatment weighting adjusted rates of major adverse cardiac event were similar between FKI and no-FKI group (15.1% versus 15.5%; P =0.967), this result did not change with use of imaging, proximal optimization technique, or routine versus bail-out FKI. In the 2-stent subgroup, FKI was associated with lower rates of target vessel revascularization (7.8% versus 15.9%; P =0.030) and target lesion revascularization (7.3% versus 15.2%; P =0.032). Short overlap FKI was associated with a lower rate of target lesion revascularization compared with no FKI (2.6% versus 5.4%; P =0.034), while long overlap was not (6.8% versus 5.4%; P =0.567).

Conclusions:

In patients with bifurcations or unprotected left main treated with ultrathin stents, short overlap FKI is associated with less restenosis. In a 2-stent strategy, FKI was associated with less target vessel revascularization and restenosis.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03544294.

Histopathologic and physiologic effect of bifurcation stenting: current status and future prospects

Introduction: Coronary bifurcation lesions are involved in up to 20% of all percutaneous coronary interventions (PCI). However, bifurcation lesion intervention is associated with a high complication rate, and optimal treatment of coronary bifurcation is an ongoing debate.Areas covered: Both different stenting techniques and a variety of devices have been suggested for bifurcation treatment, including the use of conventional coronary stents, bioresorbable vascular scaffolds (BVS), drug-eluting balloons (DEB), and stents dedicated to bifurcations. This review will summarize different therapeutic approaches with their advantages and shortcomings, with special emphasis on histopathologic and physiologic effects of each treatment strategy.Expert opinion: Histopathology and clinical data have shown that a more simple treatment strategy is beneficial in bifurcation lesions, achieving superior results. Bifurcation interventions through balloon angioplasty or placement of stents can importantly alter the bifurcation's geometry and accordingly modify local flow conditions. Computational fluid dynamics (CFD) studies have shown that the outcome of bifurcation interventions is governed by local hemodynamic shear conditions. Minimizing detrimental flow conditions as much as possible should be the ultimate strategy to achieve long-term success of bifurcation interventions.

The efficacy of modified jailed balloon technique for true bifurcation lesions

OBJECTIVE

To evaluate the short-, long-term clinical and angiographic outcomes after treatment of true bifurcation lesions using a modified jailed balloon technique (MJBT).

BACKGROUND

Percutaneous coronary intervention (PCI) for true bifurcation lesions has high risk for adverse events. Side branch (SB) occlusion is one of the most serious complications. Therefore, novel strategies to avoid SB occlusion during main branch stenting and to keep its patency are important.

METHODS AND RESULTS

Between February 2015 and February 2018, 328 patients with 349 true bifurcation lesions underwent PCI using MJBT. True bifurcation lesions were defined as Medina classifications (1.1.1), (1.0.1) or (0.1.1) lesions. We investigated the procedural and long-term clinical outcomes. Furthermore, angiographic outcomes were assessed at follow-up diagnostic angiography. The mean age of patients was 71.6 ± 9.9 years. Procedural success was achieved in all patients; postoperative SB occlusion was noted in only one patient (0.3%). The cumulative incidence of all-cause death was 23 patients (7.0%) in the follow-up period (median 717 days). Target lesion revascularization was performed in 19 patients (5.8%) with 23 lesions (6.6%), and 0.6% of myocardial infarction and 0% of definite stent thrombosis were observed. Angiographic follow-up was performed in 243 patients (74.1%); the percent diameter stenosis in SB was not significantly different between after the index procedure and follow-up angiography.

CONCLUSIONS

This MJBT is safe and effective in preserving SB patency for true bifurcation lesions. Furthermore, long-term clinical and angiographic outcomes after MJBT are feasible.

Critical aspects of balloon position during final proximal optimization technique (POT) in coronary bifurcation stenting

OBJECTIVES

In a coronary bifurcation bench model, to determine the effects of side branch (SB) wire crossing position and balloon position on the stent scaffolding after the final proximal optimization technique (POT).

BACKGROUND

POT performed as a final step after SB dilatation or kissing balloon inflation (KBI) has been widely advocated despite limited evidence.

METHODS

Thirty-one stent implantations in bifurcation phantoms were performed using a one-stent provisional technique with (KBI) (n = 13), with POT-side-POT technique (n = 12) or with the two-stent culotte technique (n = 6). SB wiring was performed through either a proximal or a distal stent cell and confirmed by optical coherence tomography. Final POT was performed with the balloon positioned either across or proximal to the SB takeoff. The area of the opened stent cell in front of the SB was assessed by 3D reconstructed microcomputation tomography scans performed before and after Final POT.

RESULTS

In cases with metallic carina, final POT across the SB takeoff caused SB rejailing. Regardless of stent technique and wire position, a Final POT across the SB takeoff reduced the SB cell opening area by 43% [32%;58%] (n = 15). The largest reduction (54-70%) was found after the POT-side-POT technique in procedures with a proximal wiring. Final POT performed proximal to the SB takeoff caused limited or no SB cell opening area reduction (4% [0.6%;6%] [n = 16]).

CONCLUSION

Final POT with balloon positioned across the SB takeoff in a narrow angle bifurcation reduces largest stent cell area in front of the SB ostium and may cause SB rejailing in cases with metallic carina.

Local fluid dynamics in patients with bifurcated coronary lesions undergoing percutaneous coronary interventions

Although the coronary arteries are uniformly exposed to systemic cardiovascular risk factors, atherosclerosis development has a non-random distribution, which follows the local mechanical stresses including flow-related hemodynamic forces. Among these, wall shear stress plays an essential role and it represents the major flow-related factor affecting the distribution of atherosclerosis in coronary bifurcations. Furthermore, an emerging body of evidence suggests that hemodynamic factors such as low and oscillating wall shear stress may facilitate the development of in-stent restenosis and stent thrombosis after successful drug-eluting stent implantation. Drug-eluting stent implantation represents the gold standard for bifurcation interventions. In this specific setting of interventions on bifurcated lesions, the impact of fluid dynamics is expected to play a major role and constitutes substantial opportunity for future technical improvement. In the present review, available data is summarized regarding the role of local fluid dynamics in the clinical outcome of patients with bifurcated lesions.

Angiographic Restenosis in Coronary Bifurcations Treatment with Regular Drug Eluting Stents and Dedicated Bifurcation Drug-Eluting BiOSS Stents: Analysis Based on Randomized POLBOS I and POLBOS II Studies

Aim

The marked variation in bifurcation anatomy has brought about an ongoing search for stents specifically constructed for coronary bifurcations. This study aimed to analyze the angiographic restenosis prevalence and patterns and predictors of different patterns in dedicated bifurcation BiOSS® vs. current generation drug-eluting stents implanted in coronary bifurcation lesions based on data from two clinical trials POLBOS I and II.

Methods

Dedicated bifurcation BiOSS® stents were compared with drug-eluting stents (DES) in patients with stable coronary artery disease (CAD) or nonST elevation acute coronary syndrome (NSTE-ACS) (POLBOS I: paclitaxel eluting BiOSS® Expert vs. DES; POLBOS II: sirolimus eluting BiOSS® LIM vs. DES). Provisional T-stenting was the default treatment. Morphological pattern of in-stent restenosis according to the modified Mehran classification adopted for bifurcation lesions was assessed with bifurcation dedicated quantitative coronary angiographic software (CAAS 5.11, Pie Medical Imaging BV, the Netherlands).

Results

In total, 445 patients (222 patients in BiOSS group and 223 patients in DES group) were included into the analysis. In BiOSS group 24 cases of angiographic restenosis (10.8%) were recorded, and in DES group-17 cases (7.6%) at 12 months follow-up (angiographic control rate at follow-up-90.3%). In the BiOSS group most frequent medina classification in restenotic cases was 0.0.1 (25%), whereas in DES-0.0.1 and 0.1.1 (23.5% each). In multivariate regression analysis proximal optimization technique was associated with the lowest chance for restenosis (OR 0.15, 95% CI 0.06-0.33), whereas diabetes on insulin was associated with the highest risk of restenosis (OR 4.21, 95% CI 1.48-11.44).

Conclusions

The angiographic restenosis pattern and rate was similar between BiOSS stents and DES in coronary bifurcation lesions.

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

Background

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

Methods

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

Results

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

Conclusion

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

Trial registration number

NCT01496638.

Optimal Site for Proximal Optimization Technique in Complex Coronary Bifurcation Stenting: A Computational Fluid Dynamics Study

BACKGROUND/PURPOSE

The optimal position of the balloon distal radio-opaque marker during the post optimization technique (POT) remains debated. We analyzed three potential different balloon positions for the final POT in two different two-stenting techniques, to compare the hemodynamic effects in terms of wall shear stress (WSS) in patients with complex left main (LM) coronary bifurcation.

METHODS/MATERIALS

We reconstructed the patient-specific coronary bifurcation anatomy using the coronary computed tomography angiography (CCTA) data of 8 consecutive patients (6 males, mean age 68.2± 18.6 years) affected by complex LM bifurcation disease. Subsequently a virtual bench test was performed in each patient using two different double stenting techniques represented by the DK and Nano crush using the reconstruction of Orsiro stents (Biotronik IC, Bulack, Switzerland).

RESULTS

A significant reduction in the mean WSS values in all the lesion's sites was observed when the final POT was performed 1 mm distally the carina cut plane in both techniques. Moreover, a significant improvement in the mean WSS values of the entire SB (e.g. LCX) was obtained performing the POT 1 mm distally to the carina cut plane. The proximal POT resulted in larger area of lower WSS values at the carina using both the Nano crush and the DK crush techniques.

CONCLUSIONS

In patients with complex LM bifurcation disease the use of a final POT performed 1 mm distally to the carina cut plane might results in more favorable WSS patterns (i.e. higher WSS values) along all stented segments and, especially, along the entire LCX lesions.

Accuracy of RESOLVE score derived from coronary computed tomography versus visual angiography to predict side branch occlusion in percutaneous bifurcation intervention

INTRODUCTION

Visually estimated angiographic V-RESOLVE score was developed as a simple and accurate prediction tool for side branch (SB) occlusion in patients undergoing coronary bifurcation intervention. Data on the use of coronary computed tomography angiography (coronary CTA) for guiding percutaneous coronary intervention in bifurcation lesions is scarce.

OBJECTIVES

We aimed to validate the ability of quantitative CTA-derived RESOLVE score for predicting SB occlusion in coronary bifurcation intervention and to compare its predictive value with that of the angiography-based V-RESOLVE score.

METHODS

We included 363 patients with 400 bifurcation lesions. Angiographic V-RESOLVE score and CTA-derived RESOLVE score were calculated utilizing the weights from the QCA-based RESOLVE score. The scoring systems were divided into quartiles, and classified as the non-high-risk group and the high-risk group. Accuracy was assessed using areas under the receiver-operator characteristic curve (AUC). SB occlusion was defined as any decrease in Thrombolysis in Myocardial Infarction flow grade (including the absence of flow) in the SB after main vessel stenting.

RESULTS

In total, 28 SB occlusions (7%) occurred. CTA-derived RESOLVE and V-RESOLVE scores achieved comparable predictive accuracy (0.709 vs. 0.752, respectively, p = 0.531) for predicting SB occlusion, and the analysis of AUC for each constituent element of the scores did not show any significant difference between CTA and visual angiography. The total net reclassification index was -18.6% (p = 0.194), and there were no significant differences in the rates of SB occlusion in the non-high-risk group (4.9% vs. 3.8%, p = 0.510) and the high-risk group (13.8% vs. 18.6%, p = 0.384) between CTA-derived RESOLVE and V-RESOLVE scores.

CONCLUSIONS

The quantitative CTA-derived RESOLVE score is an accurate and reliable alternative to the visually estimated angiographic V-RESOLVE score for prediction of SB occlusion in coronary bifurcation intervention.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT03709836.

Comparison of diagnostic performance in assessing the rewiring position into a jailed side branch between online 3D reconstruction systems version 1.1 and 1.2 derived from optical frequency domain imaging

The three-dimensional reconstruction of optical coherence tomography and optical frequency domain imaging (3D-OCT/OFDI) helps optimize bifurcation percutaneous coronary interventions (PCIs) with side branch (SB) dilatation by identifying the optimal rewiring position. 3D-OCT/OFDI’s diagnostic performance for assessing the rewiring position into a jailed SB is unknown. We retrospectively evaluated the diagnostic performances of a conventional (ver. 1.1) and a new (ver. 1.2) online 3D-OFDI reconstruction system based on an offline 3D reconstruction system’s performance. We analyzed 45 patients’ 52 OFDI pullbacks with main vessel stenting followed by rewiring into a jailed SB for coronary bifurcation lesions. We counted the undetected stent struts in the polygon of confluence as the stent detection performance. We assessed the diagnostic agreement regarding the rewiring position into a jailed SB by the three 3D reconstruction systems. The percentage of undetected struts and the diagnostic agreement of ver.1.2 were significantly better than those of ver.1.1 [5.1 ± 5.1% vs. 30.2 ± 14.2%; p < 0.0001, and 94.2% (49/52) vs. 76.9% (40/52); p = 0.0120]. The new online 3D-OFDI reconstruction system provides better diagnostic performance than the conventional online system for assessing the rewiring position into a jailed SB.

Prospective evaluation of drug eluting self-apposing stent for the treatment of unprotected left main coronary artery disease: 1-year results of the TRUNC study

OBJECTIVES

To assess long-term safety and efficacy of the Xposition S self-apposing stent in the treatment of unprotected left main coronary artery (ULMCA) disease.

BACKGROUND

Percutaneous intervention with stents has emerged as a valid alternative to surgical revascularization to treat ULMCA disease. Conventional balloon-expandable stents face technical challenges, particularly in large left main diameter requiring extensive optimization and side branch access in distal bifurcation. Xposition S allows for optimal apposition, bridging diameter differences, and allows expansion to vessel diameters up to 6.0 mm.

METHODS

Between June 2016 and July 2017, 205 patients were enrolled in this international, prospective, multicenter registry. Patients with SYNTAX score ≥ 33 or recent STEMI were excluded. IVUS during procedure was performed in a prespecified subgroup of 50 patients. The primary clinical endpoint was 12 months Target lesion failure (TLF) and the primary efficacy endpoint was angiographic success.

RESULTS

Distal left main bifurcation was involved in 92.7%, treated with provisional approach in most cases (79.4%). TLF rate at 12 months was 8.3%, which was defined as a composite of cardiac death (2.0%), target-vessel MI (2.9%), and TLR (5.4%). Most revascularizations occurred at SB ostium. IVUS analysis demonstrated optimal stent apposition with only one reported malapposition and promising poststenting minimal stent area measures.

CONCLUSIONS

The TRUNC study confirms that Xposition S self-apposing stent is a valid and feasible option for the treatment of ULMCA disease. Such results were reached without the systematic need of stent optimisation techniques, focusing mainly on lesion treatment.

Consecutive Jailed- and Kissing-Corsair Technique: Side Branch Protection and Dilation during Stent Implantation

The primary concern in percutaneous coronary intervention for bifurcation lesions is occlusion of a side branch after stenting of a main branch, especially in high-risk patients. We describe a novel technique, consecutive jailed- and kissing-Corsair technique, using a Corsair microcatheter for protection of side branches in bifurcation lesions.

Calcific lesion preparation for coronary bifurcation stenting

Bifurcating coronary lesions are a very common challenge in interventional cardiology because of the technical complexity in their treatment, the risk of side branch occlusion and an overall worse outcome when compared to non-bifurcating lesions. The presence of calcifications represents further complexity due to the difficulty in device delivery and stent expansion as well as enhanced risk of side branch occlusion. Rotational and orbital atherectomy, scoring and cutting balloons, coronary lithoplasty are available tools which have been introduced over the last three decades to overcome such issue. Nevertheless, their application in different contexts of bifurcations presents specific caveats and the studies directed at comparing such techniques have never been expressly oriented in the subset of the bifurcating lesion. In this paper, we review these devices and their usefulness in bifurcations by analyzing consistent data from clinical trials, and we propose a practical algorithm for the treatment of severely calcified bifurcating lesions according to their anatomical features.

[Hot issues in bifurcation lesions PCI in 2019]

Coronary bifurcations are involved in 15-20% of all percutaneous coronary interventions (PCI) and remain one of the most challenging lesions in interventional cardiology in terms of procedural success rate as well as long-term cardiac events. The optimal management of bifurcation lesions is still debated but involves careful assessment, planning and a sequential provisional approach. The preferential strategy for PCI of bifurcation lesions remains to use main vessel (MV) stenting with a proximal optimisation technique (POT) and provisional side branch (SB) stenting as a preferred approach. Final kissing balloon inflation is not recommended in all cases. In the minority of lesions where two stents are required, careful deployment and optimal expansion are essential to achieve a long-term result. Intracoronary imaging techniques (IVUS, OCT) and FFR are useful endovascular tools to achieve optimal results.

Percutaneous coronary intervention for obstructive bifurcation lesions: the 14th consensus document from the European Bifurcation Club

The European Bifurcation Club recommends an approach to a bifurcation stenosis which involves careful assessment, planning and a sequential provisional approach. In the minority of lesions where two stents are required, careful deployment and optimal expansion are essential to achieve a long-term result.

Use of rotablation to rescue a “fractured” micro catheter tip: A case report

BACKGROUND

High-speed rotational atherectomy (HSRA) is most commonly used to modify calcified coronary artery lesions to facilitate stent deployment and expansion. The use of HSRA as an emergency rescue technique to release a fractured micro-catheter has not been described. We report the use of HSRA in a case of a fracture trapped corsair tip that was impeding coronary flow causing a ST elevation myocardial infarct.

CASE SUMMARY

A 79 years old male was scheduled for elective percutaneous coronary intervention (PCI) to his left anterior descending artery (LAD). Given its calcific nature, a decision was made for upfront rotablation. During procedural preparations, the tip of an employed micro-catheter was separated from the shaft resulting in obstructing coronary flow and ST-segment elevation. The consensus was for an attempt bail out PCI strategy. A rotafloppy wire was advanced to the distal LAD using a corsair micro-catheter which was placed proximal to the occlusion site. Modification of the mid LAD segment was performed, resulting in mobilising the corsair tip, and deflecting it to a small diagonal branch. Following serial predilation, the procedure was completed using two overlapping drug eluting stents, jailing the corsair tip in the diagonal branch. The patient made uneventful recovery and was clinically stable at one year follow up.

CONCLUSION

HSRA may be offered as a bailed-out strategy to rescue fractured and jailed micro-catheter tip in high risk surgical cases.

Optical Coherence Tomography Tissue Coverage and Characterization with Grey-Scale Signal Intensity Analysis After Bifurcation Stenting with a New Generation Bioabsorbable Polymer Drug-Eluting Stent

PURPOSE

Bifurcation stenting is thought to be associated with delayed healing and a subsequent risk of stent failure. The aim of this study was to further evaluate healing of thin-strut bioabsorbable polymer everolimus-eluting stents (EES) post bifurcation stenting by optical coherence tomography (OCT) including grey-scale signal intensity (GSI) analysis.

METHODS

Patients undergoing bifurcation stenting with a planned two-stent approach using EES with OCT follow-up at 3-6 months post-stenting were included in this study. Morphometric analysis of contiguous cross-sections was performed at 1 mm longitudinal intervals within the stented segment. GSI analysis of neointimal regions of interest (ROI) overlying stent struts was performed for each of these cross-sections. Tissue coverage was classified as mature or immature.

RESULTS

Data on a total of 31 lesions (17 cases) was available at a median of 168 days post stenting. Mean length of stented segments was 27.7 ± 16.6 mm. The mean minimum stent area was 6.50 ± 2.71 mm² while the mean stent area was 8.69 ± 3.08 mm². Amongst a total of 847 assessed frames, 9716 struts were visible. Overall strut coverage was 95.9%; 0.3% of struts were malapposed. The mean thickness of neointimal coverage was 100.95 ± 42.03 μm and the mean percentage area stenosis was 9.03 ± 7.80%. A total of 53.79% of ROIs were classified as mature.

CONCLUSIONS

After implantation of EES in bifurcation lesions, rates of uncovered and malapposed struts were low. GSI analysis showed that more than half of neointimal areas analyzed were classified as mature in keeping with advanced vessel healing.

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Treatment of Unprotected Left Main Stenosis

PURPOSE OF REVIEW

This article reviews the latest data on unprotected left main (ULM) percutaneous coronary intervention (PCI) versus coronary artery bypass graft (CABG) surgery, with a focus on the NOBLE and EXCEL trials.

RECENT FINDINGS

In EXCEL trial, the primary endpoint at 3 years was 15.4% in the PCI group and 14.7% in the CABG group (p = 0.02 for non-inferiority of PCI versus CABG). In NOBLE, the primary endpoint at 5 years was 28% and 18% for PCI and CABG, respectively (HR 1.51, CI 1.13-2.0, which did not meet the criteria for non-inferiority of PCI to CABG; p for superiority of CABG was 0.0044). Higher repeat revascularization and non-procedural myocardial infarction were noted in PCI group but there was no difference in all-cause or cardiac mortality between the two groups. A heart team approach with appropriate patient selection, careful assessment of LM lesions, and meticulous procedural technique makes PCI a valid alternative to CABG for ULM stenosis.

Concept and practice of transradial 5 French percutaneous treatment of coronary bifurcation lesions

OBJECTIVES

To assess the efficacy and safety of transradial 5 French percutaneous treatment of coronary bifurcations using conventional devices.

BACKGROUND

Radial artery is smaller than femoral artery, and its size may potentially limit transradial intervention, especially when coronary anatomy is not known.

METHODS

Patients with bifurcations lesions undergoing transradial 5 French ad hoc revascularization were treated according to provisional side branch (SB) stenting followed by the POT-SB dilation-final POT sequence. Only conventional devices were used.

RESULTS

Overall, 80 patients (58 men, 65 ± 10 years) were enrolled. True bifurcations accounted for 64% of cases, with the left anterior descending artery/diagonal branch being the most frequent bifurcation site (n = 37, 46%) and left main coronary artery bifurcation being treated in 6 (8%) patients. Angiographic success was achieved in 78 (97.5%) patients through a 5 French guiding catheter whereas in two cases, a 5-6 French guiding catheter upgrade was required to optimize SB treatment after the main bifurcation vessel have been secured. Overall, procedural success was achieved in all but one patient who had periprocedural necrosis following multivessel PCI. Another patient underwent target bifurcation revascularization because of a critical restenosis in a significant SB yielding an acute coronary syndrome five months after the index procedure.

CONCLUSIONS

This study demonstrates the feasibility of transradial 5 French bifurcation intervention with nondedicated devices and preliminary supports its efficacy and safety over a wide range of bifurcation anatomy and complexity.

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

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

Mid-term outcomes after percutaneous interventions in coronary bifurcations

BACKGROUND

The optimal treatment of patients undergoing percutaneous coronary interventions (PCI) for lesions located at coronary bifurcations is still debated.

METHODS

Data on 5036 consecutive patients who underwent PCI on coronary bifurcation at 17 major coronary intervention centers between January 2012 and December 2014 were collected.

RESULTS

Follow-up at a median 18 months (IQR 11-28) was available for 4506 patients (89%). Major Adverse Cardiac Events (MACE) occurred in 395 patients (8.8%): cardiac death in 152 (3.4%), myocardial infarction, excluding periprocedural, in 156 (3.5%) and stent thrombosis in 110 cases (2.4%). At multivariable Cox regression, left ventricular ejection fraction ≤30% (P < 0.001), bail-out stenting (beyond a planned strategy of either single or double stenting) (P < 0.001), admission for an acute coronary syndrome (P < 0.001), age >66 years (P < 0.001), multivessel disease (P < 0.001) and diabetes (P < 0.001) were independently associated with MACE. Sensitivity analysis identified premature discontinuation of dual antiplatelet therapy (DAPT) (P < 0.001) and side branch (SB) lesion length ≥9 mm (P < 0.05) as additional independent predictors of MACE.

CONCLUSIONS

Beyond traditional risk factors, multivessel disease, the length of the SB lesion, "bail-out" stenting and premature DAPT discontinuation are independent predictors of mid-term MACE after PCI of coronary bifurcations. This highlights the importance of a carefully planned PCI strategy and adequate therapy adherence to improve the clinical outcomes in these patients.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01967615.

Rational and design of the European randomized Optical Coherence Tomography Optimized Bifurcation Event Reduction Trial (OCTOBER)

Background

Percutaneous coronary intervention in complex bifurcation lesions is prone to suboptimal implantation results and is associated with increased risk of subsequent clinical events. Angiographic ambiguity is high during bifurcation stenting, but it is unknown if procedural guidance by intravascular optical coherence tomography (OCT) improves clinical outcome.

Methods and Design

OCTOBER is a randomized, investigator-initiated, multicenter trial aimed to show superiority of OCT-guided stent implantation compared to standard angiographic-guided implantation in bifurcation lesions. The primary outcome measure is a 2-year composite end point of cardiac death, target lesion myocardial infarction, and ischemia-driven target lesion revascularization. The calculated sample size is 1,200 patients in total, and allocation is 1:1. Eligible patients have stable or unstable angina pectoris or stabilized non–ST elevation myocardial infarction, and a coronary bifurcation lesion with significant main vessel stenosis and more than 50 % stenosis in a side branch with a reference diameter ≥2.5mm. Treatment is performed by the provisional side branch stenting technique or 2-stent techniques, and the systematic OCT guiding protocol is aimed to evaluate (1) plaque preparation, (2) lesion length, (3) segmental reference sizes, (4) lesion coverage, (5) stent expansion, (6) malapposition, (7) wire positions, and (8) ostial results.

Implications

A positive outcome of the OCTOBER trial may establish OCT as a routine tool for optimization of complex percutaneous coronary intervention, whereas a negative result would indicate that OCT remains a tool for ad hoc evaluation in selected cases.

A Novel Double Side Branch Protection Technique for a Left Main Trifurcation Lesion: Simultaneous Jailed Balloon and Jailed Corsair Technique

Percutaneous coronary intervention for left main trifurcation disease is challenging. Although side branch protection techniques such as the jailed balloon technique and jailed Corsair technique are the established methods for treatment of coronary bifurcation lesions, little is known regarding the application and feasibility of these techniques for left main trifurcation disease. We herein describe a 72-year-old man with angina pectoris who was successfully treated with percutaneous coronary stent implantation for a left main trifurcation lesion. In this case, we performed a novel double side branch protection technique, the simultaneous jailed balloon and jailed Corsair technique, with a single 8 Fr guiding catheter. This is the first case report to highlight the feasibility and efficacy of combined use of the jailed balloon and jailed Corsair techniques during percutaneous coronary intervention for left main trifurcation disease.

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.

Benefits of final proximal optimization technique (POT) in provisional stenting

AIMS

Initial proximal optimization technique (POT) in provisional stenting improves global malapposition, side-branch (SB) obstruction (SBO) and conservation of arterial circularity. The specific mechanical effects of a final POT sequence concluding the main provisional stenting techniques, on the other hand, are unknown.

METHODS AND RESULTS

Synergy™ stents were implanted on fractal coronary bifurcation bench models using the main provisional stenting techniques (n = 5 per group): kissing-balloon inflation (KBI), snuggle, and rePOT (initial POT + SB inflation + final POT). Final results were quantified on 2D and 3D OCT before and after final POT. Whichever the technique, final POT significantly decreased global malapposition (from 7.6 ± 5.3% to 2.2 ± 2.5%, p < 0.05) and proximal elliptic deformation (from 1.15 ± 0.07 to 1.09 ± 0.04, p < 0.05), without impact on SBO (from 11.5 ± 9.6% to 12.9 ± 10.6%, NS). However, final POT failed to completely correct the elliptic deformation induced by balloon juxtaposition during the KBI and snuggle techniques, with final elliptic ratios of 1.11 ± 0.03 and 1.11 ± 0.04 respectively, significantly higher than with the complete rePOT sequence: 1.05 ± 0.02 (p < 0.05).

CONCLUSIONS

Like initial POT, final POT is recommended whatever the provisional stenting technique used. However, final POT fails to completely correct all proximal elliptic deformation associated with "kissing-like" techniques, in contrast to results with the rePOT sequence.