Treatment of coronary bifurcation lesions, part II: implanting two stents. The 16th expert consensus document of the European Bifurcation Club

Mini-crush or Nano-crush Stenting Technique for Complex Coronary Bifurcation Lesions: The Multicenter MINANO Registry

BACKGROUND

This multicenter study aimed to retrospectively evaluate the mid-term clinical outcomes of mini-crush (MCT) and nano-crush (NCT) techniques in patients with complex bifurcation lesions (CBLs).

METHODS

The study comprised 431 patients [male: 318 (73.8%), mean age: 60.96 ± 10.34 years] who underwent bifurcation PCI between January 2018 and December 2023 were included in the study from six tertiary centers. The primary endpoint was defined as the major cardiovascular events (MACE), which include cardiac death, target vessel myocardial infarction (TVMI), or clinically driven target lesion revascularization (TLR). This is the first study to compare the clinical outcomes of MCT and NCT in patients with CBL.

RESULTS

The initial revascularization strategy was MCT in 302 (70%) cases and NCT in 129 (30%) patients. SYNTAX scores [24.33±6.54 vs 24.43±5.45, p=0.707] were comparable in both groups. The incidence of MACE (18.6 vs. 10.9%, p=0.031), TVMI (11.6 vs 5.6%, p=0.030), and clinically driven TLR (14 vs. 6%, p=0.006) were significantly higher in the NCT group compared to the MCT group. Being in the MCT group (HR: 0.549, p=0.035), high SYNTAX score (HR: 1.105, p<0.001), non-fatal intra-procedural complications (HR: 3.269, p<0.001), proximal side-branch optimization (HR: 0.451, p=0.013), diabetes mellitus (HR: 2.263, p=0.009), and chronic kidney disease (HR: 1.948, p=0.024) were found to be independent predictors of MACE.

CONCLUSION

This non-randomized study suggests that MCT was associated with better mid-term MACE, TVMI, and clinically driven TLR rates compared with NCT in patients with CBLs.

Multimodal Imaging of Coronary Bifurcation TAP Procedures Utilizing Visible Heart® Methodologies: EBC Recommended Steps and Bailout Procedures

In some cases it is critical to clinically perform coronary bifurcation stenting to minimize the potential risk for restenosis and/or stent thrombosis. The European Bifurcation Club (EBC) has provided guidelines for optimally performing such procedures. Yet, sometimes such procedures do not go as planned, and in some cases bailout procedures are required. Here we utilized Visible Heart® (VH) methodologies and multimodal visualizations to better understand each step for optimally performed T and small protrusion (TAP) procedures, as well as those in which complications occurred. These studies were performed within reanimated swine hearts in which endoscopes, fluoroscopy, and optical coherence tomography (OCT) could readily be used. Additionally, because these procedures were performed in reanimated hearts, one could intentionally cause complications, so to perform bailout procedures. Finally, following these procedures each specimen was micro CT scanned, and high resolution computational models (~40 microns) were reconstructed of the final outcomes.

Comparative Short-Term Outcomes of Double-Kissing Culotte and Culotte Techniques in Acute Coronary Syndrome from the Lower Silesia Culotte Bifurcation Registry

Background/Objectives: The double-kissing (DK) culotte technique is a modification of the culotte technique that employs initial kissing balloon inflation after first stent implantation. The DK culotte technique may improve strut apposition and procedural outcomes; however, data on its efficacy and safety remain limited. This study aimed to investigate the short-term outcomes of bifurcation percutaneous coronary intervention (PCI) using the DK culotte technique compared with those of the culotte technique in patients with acute coronary syndrome (ACS). Methods: This two-center, observational, retrospective study included patients with ACS. Out of 12,132 screened patients, 117 and 122 underwent DK culotte and culotte PCIs, respectively, with 117 and 57 patients remaining after propensity score matching. The primary endpoint was 1-year target lesion failure (TLF), which included cardiovascular death, target vessel myocardial infarction or clinically indicated target lesion revascularization (TLR). Secondary endpoints included major adverse cardiac events (MACEs) comprising myocardial infarction, cardiac death, and TLR; contrast medium amount (mL); and cumulative radiation dose (mGy). Results: At 1 year, TLF occurred in 7% and 12% of the DK culotte and culotte groups, respectively (p = 0.17). No significant differences were observed in MACEs between the groups (13% DK culotte vs. 19% culotte; p = 0.12). Additionally, the DK culotte technique did not cause higher contrast medium usage or cumulative radiation dosage. Conclusions: No statistically significant differences were found in TLF and MACE reduction between ACS patients treated with the DK culotte technique and the culotte technique. The observed trend favoring the DK culotte needs further validation in prospective studies.

Safety and Efficacy of BioMime Sirolimus-Eluting Stent System in All-Comers Real-World Population With Coronary Artery Stenosis: MILES Global Registry

Background

This study evaluated the safety and efficacy of BioMime sirolimus-eluting stent (SES) system, with an ultra-low strut thickness (65 µm), in real-world all-comers population with coronary artery stenosis (CAD).

Methods

This was a post-marketing, multicenter, single-arm, observational clinical registry among patients undergoing intervention for CAD. Patients were clinically followed up at 1, 9, 12, and 24 months after the index percutaneous coronary intervention. Four major indications, namely long stents of > 30 mm, stents with diameters of 4 and 4.5 mm, bifurcation subgroup, and chronic total occlusion (CTO) were evaluated as pre-specified subsets.

Results

A total of 771 patients (1,079 treated lesions) from 23 sites were included in this study. The mean length and diameter of the implanted stents were 25.57 ± 9.35 mm and 3.00 ± 0.44 mm, respectively. The mean minimum lumen diameter before and after the procedure was 1.00 ± 1.69 mm and 2.96 ± 1.35 mm, respectively. The cumulative rates of major adverse cardiovascular events (MACEs) and stent thrombosis (ST) at 1, 9, 12, and 24 months were 1.05%, 3.13%, 4.04%, 5.64% and 0%, 0.13%, 0.28%, 0.28%, respectively. In a subset with > 30 mm long stents, the cumulative rate of MACEs was 0.4%, 4.6%, 5.12%, and 7.01% at 1, 9, 12, and 24 months, respectively. The corresponding rates of ST were 0%, 0.42%, 0.43%, and 0.44%, indicating constant rate of ST after 9 months. In a subset of 4 and 4.5 mm diameter stents, the cumulative rate of MACEs was high (0%, 6.25%, 6.25%, and 10.41%) at 1, 9, 12, and 24 months, respectively. However, there was no case of ST until 24 months. In patients with bifurcation lesions, the cumulative rates of MACEs and ST were 2.46%, 6.32%, 11.53%, 16.21% and 0%, 1.27%, 1.28%, 1.35% at 1, 9, 12, and 24 months follow-up. In patients with chronic total occlusion, the cumulative rates of MACEs and ST were 0.79%, 5.04%, 6.83%, 7.07% and 0%, 0.84%, 0.85%, 0.88% at 1, 9, 12, and 24 months, respectively, indicating constant rate of ST after 9 months.

Conclusions

The BioMime SES demonstrated good safety and efficacy outcomes at 24-month follow-up, with low rates of MACEs and ST in patients with CAD in the real-world setting.

Long-term cardiovascular outcomes after mini-crush or T and minimal protrusion techniques in complex bifurcation lesions: the EVOLUTE-CRUSH III study

BACKGROUND

Mini-crush (MC) and T-stenting and small protrusion (TAP) techniques are frequently used, but the long-term comparison of both techniques in patients with complex bifurcation lesions (CBLs) is still a debatable issue. This study sought to retrospectively evaluate the long-term outcomes of MC and TAP techniques in patients with CBLs.

METHODS

A total of 271 patients [male: 202 (78.9%), mean age: 58.90 ± 10.11 years] patients in whom complex bifurcation intervention was performed between 2014 and 2023 were involved. The primary endpoint was major cardiovascular events (MACE) as the combination of cardiac death, target vessel myocardial infarction, or clinically driven-target lesion revascularization. The Cox proportional hazard models were adjusted by the inverse probability weighting approach to reduce treatment selection bias.

RESULTS

The initial management strategy was MC in 146 patients and TAP in 125 cases. MACE occurred in 52 patients (19.2%) during a mean follow-up period of 32.43 ± 16 months. The incidence of MACE (13 vs. 26.4%, P  = 0.005) and major cardiovascular and cerebral events (15.1 vs. 28.8%, P  = 0.006) were significantly lower in the MC group than in the TAP group. Additionally, the incidence of definite or probable stent thrombosis was numerically lower in the MC group compared with the TAP group but did not differ significantly (2.7 vs. 8%, P  = 0.059). The long-term MACE was notably higher in the TAP group than the MC group [adjusted hazard ratio (inverse probability weighted): 1.936 (95% confidence interval: 1.053-3.561), P  = 0.033].

CONCLUSION

In this study involving patients with CBLs, percutaneous coronary intervention with the MC technique had better long-term outcomes than the TAP technique.

Long-term clinical and angiographic outcome of T-and protrusion technique with ultrathin strut drug eluting stents

OBJECTIVES

Data about coronary bifurcations treated with ultrathin strut drug-eluting stents (DES) using T-and-protrusion (TAP) technique is limited.

METHODS

In this study, a total of 84 consecutive patients, who underwent bifurcation percutaneous coronary intervention (PCI) with TAP technique using Orsiro® DES (Biotronik, Berlin, Germany), were included. All pre- and post-procedural data, as well as 1- and 2-year follow-up angiograms, were analyzed. Primary endpoints were procedural success and target lesion failure (TLF); secondary endpoints were all-cause mortality and major adverse cardiac and cerebrovascular events (MACCE) during follow-up.

RESULTS

Procedural success was achieved in 100% of cases. TLF rate was higher in patients presented with acute coronary syndrome compared to the ones with chronic coronary syndrome (19% vs. 5% p = 0.09). All-cause mortality was 30% during follow-up, from which 26% was due to non-cardiovascular cause, and the MACCE rate was 46%.

CONCLUSIONS

Coronary bifurcations treated with ultrathin strut DES showed good short-term results and were associated with acceptable cardiovascular mortality. However, in these long-term patients, the rate of MACCE and non-cardiovascular death were rather high.

Carina: A major determinant in the pathophysiology and treatment of coronary bifurcation lesions

Over the last decade, several in vivo and computational investigations have significantly advanced our understanding of the pathophysiology of coronary bifurcations, contributing to the enhancement of their percutaneous revascularization. The carina of the coronary bifurcations plays a substantial role in generating their main hemodynamic features, including distinctive flow patterns with secondary flows and specific shear stress patterns. These factors play a pivotal role in determining the susceptibility, development, and progression of atherosclerosis. The underlying pathophysiological mechanisms of atherosclerosis in coronary bifurcations are complex and multifactorial. Understanding these mechanisms is fundamental to comprehending lesions at the bifurcation level and informing future treatment strategies. This review aims to present the currently available data regarding the pathophysiological and prognostic role of the carina in coronary bifurcations, offering an interpretation of these findings from the perspective of interventional cardiologists, providing valuable insights for their clinical practice.

Contemporary State-of-the-Art PCI of Left Main Coronary Artery Disease

The left main coronary artery (LMCA) supplies over 70% of the myocardium, and significant LMCA disease is associated with high morbidity and mortality. With remarkable advances in percutaneous coronary intervention (PCI), including stent technology, antithrombotic agents, and evolving procedural techniques, PCI has become an important treatment option in clinical practice guidelines for the revascularization of LMCA disease. In contemporary clinical practice, a heart-team approach to shared decision-making, considering clinical/anatomic factors along with patient preferences, is emphasized for patients with significant LMCA disease requiring myocardial revascularization. Furthermore, recent progress in PCI procedures combined with intravascular imaging or functional guidance has resulted in significant improvements in PCI outcomes, especially for complex lesions, including LMCA disease. Nevertheless, owing to inherent anatomic complexities and frequent multivessel involvement, several unmet issues remain regarding the determination of the appropriate treatment approach for significant LMCA disease, for which further clinical research is required. This contemporary review article provides a comprehensive overview of left main PCI based on current guidelines and underlying trial data, addresses important unresolved diagnostic and therapeutic issues, and identifies future perspectives likely to advance progress in this field.

Clinical Outcomes of Double-Kissing Crush or Double-Kissing Culotte in Nonleft Main Bifurcation Lesions: The ROUTE Trial

BACKGROUND

Double-kissing (DK) crush and DK culotte are the recommended 2-stent strategies in true coronary bifurcation lesions. However, it is a matter of curiosity about which of the DK crush and DK culotte stenting techniques will have superior results. We aimed to compare the clinical outcomes of DK crush and DK culotte stenting in nonleft main coronary artery bifurcation.

METHODS

Consecutive patients who received DK crush or DK culotte technique for de novo true nonleft main coronary artery bifurcation lesion were categorized according to which treatment they received. The primary end point of the study was target lesion failure as a composite end point of target lesion revascularization, target vessel myocardial infarction, and cardiac death. Secondary end points were all-cause death and definite stent thrombosis.

RESULTS

A total of 202 patients were categorized as DK crush (101 patients) or DK culotte (101 patients) techniques. The target lesion failure had occurred frequently in the DK crush (10.9%) compared with the DK culotte (3.0%; P=0.028) that was mainly driven by increased target lesion revascularization (9.9% in the DK crush versus 3.0% in the DK culotte; P=0.045). The number of patients with target vessel myocardial infarction (3.0% in the DK crush versus 2.0% in the DK culotte; P=0.651) and cardiac death (1.0% in the DK crush versus 0.0% in the DK culotte; P=0.315) was higher in the DK crush. There were no differences in terms of definite stent thrombosis and all-cause death between groups.

CONCLUSIONS

In the present analysis, DK culotte was associated with lower 1-year target lesion failure rates compared with DK crush in true nonleft main coronary artery bifurcations.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04789161.

Duration of Dual Antiplatelet Therapy after Percutaneous Coronary Intervention of Unprotected Left Main Coronary Artery Stenosis: 6 versus 12 Months

Background/Objectives: For patients with percutaneous coronary intervention (PCI) of an unprotected left main coronary artery (uLMCA) stenosis, the optimal duration of dual antiplatelet therapy (DAPT) remains a matter of debate. The purpose of this study was to compare clinical outcomes of 6- versus 12-month DAPT duration in patients with PCI of an uLMCA and stable angina. Methods: In this retrospective analysis, we included consecutive patients of our centre who underwent PCI of uLMCA stenosis for stable angina and who received DAPT with acetylsalicylic acid and clopidogrel for either 6 or 12 months. The primary endpoint was the composite of all-cause mortality, myocardial infarction, and target lesion revascularization at one year. Secondary endpoints included individual components of the primary endpoint, definite/probable stent thrombosis, and bleeding. Clinical outcomes were assessed by unadjusted analysis and by inverse probability of treatment weighting (IPTW). Results: Out of 984 included patients, 339 (34.5%) received DAPT for 6 months and 645 (65.5%) for 12 months. The primary endpoint occurred in 51 patients (15.2%) in the 6-month group and in 104 (16.3%) in the 12-month group (p = 0.674). Incidences of stent thrombosis (0.9% versus 0.3%, p = 0.224) and BARC 3,4,5 bleeding (6% versus 5.8%, p = 0.808) were also comparable in both groups. We found no significant differences in the primary endpoint and its components or BARC 3,4,5 bleeding between 6 and 12 months. Conclusions: Our findings do not support the extension of DAPT beyond 6 months after PCI for uLMCA in patients with stable angina.

Percutaneous coronary intervention for bifurcation coronary lesions using optimised angiographic guidance: the 18th consensus document from the European Bifurcation Club

The 2023 European Bifurcation Club (EBC) meeting took place in Warsaw in October, and the latest evidence for the use of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) to optimise percutaneous coronary interventions (PCI) on coronary bifurcation lesions (CBLs) was a major focus. The topic generated deep discussions and general appraisal on the potential benefits of IVUS and OCT in PCI procedures. Nevertheless, despite an increasing recognition of IVUS and OCT capabilities and their recognised central role for guidance in complex CBL and left main PCI, it is expected that angiography will continue to be the primary guidance modality for CBL PCI, principally due to educational and economic barriers. Mindful of the restricted access/adoption of intracoronary imaging for CBL PCI, the EBC board decided to review and describe a series of tips and tricks which can help to optimise angiography-guided PCI for CBLs. The identified key points for achieving an optimal angiography-guided PCI include a thorough analysis of pre-PCI images (computed tomography angiography, multiple angiographic views, quantitative coronary angiography vessel estimation), a systematic application of the technical steps suggested for a given selected technique, an intraprocedural or post-PCI use of stent enhancement and a low threshold for bailout use of intravascular imaging.

Cardiovascular outcomes of complex bifurcation lesions following double kissing crush or nano-crush techniques: The multicenter EVOLUTE-CRUSH V study

BACKGROUND

Double kissing crush (DKC) and nano-crush (NC) techniques are frequently used, but the comparison for both techniques is still lacking. The goal of this multicenter study was to retrospectively assess the midterm clinical results of DKC and NC stenting in patients with complex bifurcation lesions (CBLs).

METHODS

A total of 324 consecutive patients [male: 245 (75.6%), mean age: 60.73 ± 10.21 years] who underwent bifurcation percutaneous coronary intervention between January 2019 and May 2023 were included. The primary endpoint defined as the major cardiovascular events (MACE) included cardiac death, target vessel myocardial infarction (TVMI), or clinically driven target lesion revascularization (TLR). Inverse probability weighting (IPW) was performed to reduce treatment selection bias. This is the first report comparing the clinical outcomes of DKC and NC stenting in patients with CBL.

RESULTS

The initial revascularization strategy was DKC in 216 (66.7%) cases and NC in 108 (33.3%) patients. SYNTAX scores [25.5 ± 6.73 vs. 23.32 ± 6.22, p = 0.005] were notably higher in the NC group than the DKC group. The procedure time (76.98 ± 25.1 vs. 57.5 ± 22.99 min, p = 0.001) was notably higher in the DKC group. The incidence of MACE (18.5 vs. 9.7%, p = 0.025), clinically driven TLR (14.8 vs. 6%, p = 0.009), and TVMI (10.2 vs. 4.2%, p = 0.048) were notably higher in the NC group than in the DKC group. The midterm MACE rate in the overall population notably differed between the NC group and the DKC group (adjusted HR (IPW): 2.712, [95% CI: 1.407-5.228], p = 0.003).

CONCLUSION

In patients with CBLs, applying the DKC technique for bifurcation treatment had better ischemia-driven outcomes than the NC technique.

The Balloon-Assisted Double-Kissing T-Stenting Technique: Concept, In Vitro Model, and Case Examples

Background

In complex bifurcation percutaneous coronary intervention, 2-stent strategies are often required. Commonly used 2-stent techniques can lead to suboptimal results due to their complexity. We developed the balloon-assisted double-kissing T-stenting (DKT) technique, which uses balloons to optimize stent placement, delivery, and final architecture.

Methods

With the balloon-assisted DKT technique, a balloon is inflated into the main branch (MB) to identify the best position of the side-branch (SB) stent instead of relying on angiography. DKT aims at supporting the SB ostium with stent crowns instead of distorted open cell(s), by achieving a longitudinal deformation with minimal crush of the SB stent upon implantation of the MB stent. This hypothesis was tested on a bench model. We report how the technique was performed in 2 cases and provide intracoronary imaging of the results.

Results

As hypothesized, DKT resulted in a longitudinal accordion-like deformation and minimal crush effect on bench. The SB ostium was supported by stent crowns. The SB wall opposed to the carina was well covered with crowns from the MB stent after proximal optimization technique and final kissing. The technique was successfully used in 2 complex left main cases with perfect coverage of the SB ostium as assessed with intracoronary imaging.

Conclusions

The balloon-assisted DKT is a simple technique that combines strengths of double-kissing crush and culotte techniques, results in appropriate SB ostium coverage, and deserves further investigation.

The impact of the bifurcation angle for the Nano-Crush two-stent coronary bifurcation technique on long-term outcomes in a real-world clinical population

AIM

This study aims to assess the direct impact of bifurcation angle (BA) on immediate procedural outcomes and patient prognosis post-Nano-Crush stenting for coronary bifurcation lesions.

METHODS

A retrospective analysis was conducted for all consecutive patients treated with the Nano-Crush technique across two high-volume interventional centers from January 2020 to October 2022.

PRIMARY ENDPOINT

comparison of target lesion failure rate in two cohorts based on bifurcation angle (<70° vs. ≥70°), with secondary endpoints including side branch ostium coverage, rate of successful final kissing balloon inflation (FKBI), need for conversion to another technique, and procedure length.

RESULTS

Baseline demographics included 71 patients in the BA<70° group and 49 in the BA≥70° group, with well-balanced characteristics. Angiographic characteristics revealed similar trends, including anatomic and morphological lesion characteristics (referencing Syntax score, Medina classification, and presence of calcifications). Both groups predominantly had complex coronary disease, with a baseline mean Syntax score of 24.18 ± 8.19 in the BA<70° group and 23.91 ± 7.29 in the BA≥70° group, respectively. A dedicated debulking device for lesion preparation was used in 25.35 % of patients in the first group and in 28.57 % of patients in the second group. The primary endpoint occurred in 5.63 % of patients in the BA<70° group and in 4.08 % of patients in the BA≥70° group (P = 0.7014) after ≥ 2 years of clinical follow-up. Angiographic success was achieved in 100 % of both groups, with procedural time averaging 74.99 ± 25.55 min in the BA≥70° and 76.94 ± 27.81 min in the BA<70° (P = 0.6922). The rate of successful final kissing balloon inflation was 98.59 % in the BA<70° group and 95.91 % in the BA≥70° group (P = 0.3566). The mean contrast volume was 189.54 ± 73.74 ml in BA<70° and 168.9 ± 62.77 ml in BA≥70° (P = 0.1126). Clinical follow-ups at 30 days and 2 years revealed similar outcomes and complications for each group, as summarized in Table 3.

CONCLUSIONS

Our results demonstrate that the bifurcation angle does not significantly impact long-term clinical outcomes or procedural parameters, such as side branch ostium coverage, conversion to a modified DK Crush technique, FKBI success rate, and procedure length. These findings suggest that the Nano-Crush technique can be a viable option for bifurcation lesions, irrespective of the bifurcation angle, achieving optimal side branch ostium coverage while preventing excessive protrusion into the main vessel.

Effect of negative remodeling of the side branch ostium on the efficacy of a two-stent strategy for distal left main bifurcation lesions: an intravascular ultrasound study

OBJECTIVES

To investigate whether negative remodeling (NR) detected by intravascular ultrasound (IVUS) of the side branch ostium (SBO) would affect in-stent neointimal hyperplasia (NIH) at the one-year follow-up and the clinical outcome of target lesion failure (TLF) at the long-term follow-up for patients with left main bifurcation (LMb) lesions treated with a two-stent strategy.

METHODS

A total of 328 patients with de novo true complex LMb lesions who underwent a 2-stent strategy of percutaneous coronary intervention (PCI) treatment guided by IVUS were enrolled in this study. We divided the study into two phases. Of all the patients, 48 patients who had complete IVUS detection pre- and post-PCI and at the 1-year follow-up were enrolled in phase I analysis, which aimed to analyze the correlation between NR and in-stent NIH at SBO at the 1-year follow-up. If the correlation was confirmed, the cutoff value of the remodeling index (RI) for predicting NIH ≥ 50% was analyzed next. The phase II analysis focused on the incidence of TLF as the primary endpoint at the 1- to 5-year follow-up for all 328 patients by grouping based on the cutoff value of RI.

RESULTS

In phase I: according to the results of a binary logistic regression analysis and receiver operating characteristic (ROC) analysis, the RI cutoff value predicting percent NIH ≥ 50% was 0.85 based on the ROC curve analysis, with a sensitivity of 85.7%, a specificity of 88.3%, and an AUC of 0.893 (0.778, 1.000), P = 0.002. In phase II: the TLR rate (35.8% vs. 5.3%, P < 0.0001) was significantly higher in the several NR (sNR, defined as RI ≤ 0.85) group than in the non-sNR group.

CONCLUSION

The NR of LCxO is associated with more in-stent NIH post-PCI for distal LMb lesions with a 2-stent strategy, and NR with RI ≤ 0.85 is linked to percent NIH area ≥ 50% at the 1-year follow-up and more TLF at the 5-year follow-up.

Unintended Deformation of Stents During Bifurcation PCI: An OCTOBER Trial Substudy

BACKGROUND

Unintended deformation of implanted coronary stents can lead to loss of coronary access, stent thrombosis and coronary events during follow-up. The incidence, mechanisms and clinical outcomes of unintended stent deformations (USD) during complex bifurcation stenting are not well characterized.

OBJECTIVES

In a prespecified analysis of the OCTOBER (European Trial on Optical Coherence Tomography Optimized Bifurcation Event Reduction) trial, we aimed to: 1) determine the incidence and characterize mechanisms of USD identified by optical coherence tomography (OCT); and 2) evaluate physician's detection and correction of accidental abluminal rewiring and USD.

METHODS

OCT scans were analyzed for accidental abluminal rewiring and USD. When USD was identified, the plausible mechanism was determined by analysis of all procedural OCT scans and the corresponding angiograms.

RESULTS

USD was identified by the core lab in 9.3% (55/589) of OCT-guided cases. Accidental abluminal rewiring was the cause in 44% (24/55), and guide catheter collision was the cause in 40% (22/55) of cases. USD was found in 18.5% of all cases with left main bifurcation percutaneous coronary intervention. The total incidence of abluminal rewiring was 33 in 32 OCT-guided cases (5.4%) and was corrected by physicians in 18 of 33 appearances (54.5%). The 2-year major adverse cardiac event rate for patients with untreated USD (n = 30) was 23.3%, whereas patients with confirmed or possibly corrected USD (n = 25) had no events during follow-up.

CONCLUSIONS

USD was associated with adverse procedural complications and cardiac events during follow-up when not identified and corrected. The predominant mechanisms were undetected abluminal rewiring and guide catheter collision. Left main bifurcation percutaneous coronary intervention was a particular risk with USD detected in 18.5% of cases.

Fracture and plastering of distal left main stent during double-kissing Culotte technique: a case report

Background

Acute fracture of a left main (LM) stent during angioplasty is a rare complication. Cardiologists should be aware of the risk of stent fracture (SF) following kissing balloon inflation (KBI) even if the effective diameter of the balloons does not exceed the recommended expansion limits of stents.

Case summary

A 64-year-old female with hypertension and dyslipidaemia presented with crescendo angina since three months in spite of optimal medical therapy. Coronary angiogram showed a distal LM bifurcation lesion. The patient was admitted for LM bifurcation stenting by upfront two-stent technique (inverted double-kissing Culotte technique). Following first KBI of the stent placed from left circumflex artery (LCX) to LM, there was stent deformation in the LM shaft. As we had planned the Culotte technique, we decided to exclude the fractured segment by stenting from left anterior descending artery (LAD) to LM. The stent from LAD-LM successfully excluded the fractured part of the first stent from the lumen of LM. Optical coherence tomography done after final KBI from LCX-LM revealed successful exclusion of the deformed segment of the LCX stent with mild malapposition at the site of the deformed stent. A follow-up angiogram after six months showed normal in-stent flow with no evidence of restenosis or pseudoaneurysm.

Discussion

Acute LM SF during coronary intervention can occur even if the effective cumulative diameter of the inflated balloons does not exceed the mentioned expansion limit of stents. Intravascular imaging is a helpful modality to define type of SF and its management.

The Randomized, Multicenter, Open-Label, Controlled POLBOS 3 Trial Comparing Regular Drug-Eluting Stents and the Sirolimus-Eluting BiOSS LIM C Dedicated Coronary Bifurcation Stent: Four-Year Results

This multicenter, randomized study aimed to compare the sirolimus-eluting BiOSS LIM C dedicated coronary bifurcation stent with second-generation -limus drug-eluting stents (rDESs) in the treatment of non-left main (non-LM) coronary bifurcation. The deployment of a single stent in the main vessel-main branch across a side branch was the default strategy in all patients. The primary endpoint was the rate of major cardiovascular events (cardiac death, myocardial infarction, and target lesion revascularization) at 48 months. We enrolled 230 patients, allocating 116 patients to the BiOSS LIM C group and 114 patients to the rDES group. Most procedures were elective (BiOSS vs. rDES: 48.3% vs. 59.6%, p = 0.09) and performed in bifurcations within the left anterior descending/diagonal branch (BiOSS vs. rDES: 51.7% vs. 61.4%, p = 0.15). At 48 months, there were no statistically significant differences between the BiOSS and rDES groups in terms of major adverse cardiovascular events (MACE), cardiac death, myocardial infarction (MI), or target lesion revascularization (TLR) as follows: MACEs-18.1% vs. 14.9%, HR 1.36, 95% CI 0.62-2.22, and p = 0.33; cardiac death-4.3% vs. 3.5%, HR 1.23, 95% CI 0.33-4.56, and p = 0.75; MI-2.6% vs. 3.5%, HR 0.73, 95% CI 0.17-3.23, and p = 0.68; and TLR-11.2% vs. 7.9%, HR 1.66, 95% CI 0.75-3.71, and p = 0.21. The implantation success rate of the BiOSS LIM C stent was very high, and the cumulative MACE rates were promising. The POLBOS 3 trial sets an important benchmark for treating non-LM coronary bifurcations (ClinicalTrials.gov NCT03548272).

Proximal optimization technique and percutaneous coronary intervention for left main disease: POTENTIAL-LM

BACKGROUND

Optimal stent deployment in left main (LM) bifurcation is paramount, and incomplete stent apposition may cause major adverse cardiac events (MACE). Bench studies show that the proximal optimization technique (POT) provides the best stent apposition.

AIMS

We aimed to investigate the impact of POT on clinical outcomes in patients treated for unprotected LM (ULM) disease at our institution.

METHODS

We identified 162 patients who underwent percutaneous coronary intervention (PCI) for ULM coronary disease in the Cardio-FR database. Out of these, 99 (61%) had undergone POT, while 63 patients were treated without POT. The primary outcome was the bifurcation-oriented composite endpoint (BOCE) of cardiac death, target-bifurcation myocardial infarction and target-bifurcation revascularization at maximal follow-up.

RESULTS

Mean age was 76 years, and 69% presented with acute coronary syndrome. Mean follow-up was 2.25 years (822 days). The BOCE occurred in 43 (27%) of which 20 (20%) in the POT group and 23 (37%) in the no-POT group (p = 0.009). Cardiac death occurred in 15 (15%) patients in the POT- and 17 (27%) in no-POT group (p = 0.26). Target bifurcation revascularization occurred in 4 (4%) patients in the POT- and 6 (10%) patients in the no-POT group (p = 0.19). POT In the multivariate analysis, POT was the strongest parameter and was associated with BOCE, cardiac death, occurrence of any revascularization and all-cause mortality.

CONCLUSION

The POT improves clinical outcomes. These findings strongly support the systematic use of POT in patients undergoing ULM-PCI.

Review of Progress in Interventional Therapy for Coronary Bifurcation Lesions

Despite a decade of extensive research and clinical insights, percutaneous coronary intervention strategies for coronary bifurcation lesions have remained a challenging and highly debated area. This article presents a review of the latest findings and advances in defining and classifying coronary bifurcation lesions, in vitro studies, intracoronary imaging, stenting strategies, and the deployment of drug-coated balloons. Based on current evidence, this review provides recommendations for interventional cardiologists to develop individualized interventional strategies and enhance the efficiency of stenting procedures.

Optimal Minimal Stent Area and Impact of Stent Underexpansion in Left Main Up-Front 2-Stent Strategy

BACKGROUND

We previously reported the use of minimal stent area to predict angiographic in-stent restenosis after drug-eluting stent implantation for unprotected left main (LM) disease. We aimed to evaluate the optimal minimal stent area criteria for up-front LM 2-stenting based on long-term clinical outcomes.

METHODS

We identified 292 consecutive patients with LM bifurcation stenosis who were treated using the crush technique. The final minimal stent area was measured in the ostial left anterior descending artery (LAD), ostial left circumflex artery (LCX), and distal LM. The primary outcome was 5-year major adverse cardiac events, including all-cause death, myocardial infarction, and target lesion revascularization.

RESULTS

The minimal stent area cutoff values that best predicted the 5-year major adverse cardiac events were 11.8 mm2 for distal LM (area under the curve, 0.57; P=0.15), 8.3 mm2 for LAD ostium (area under the curve, 0.62; P=0.02), and 5.7 mm2 for LCX ostium (area under the curve, 0.64; P=0.01). Using these criteria, the risk of 5-year major adverse cardiac events was significantly associated with stent underexpansion in the LAD ostium (hazard ratio, 3.14; [95% CI, 1.23-8.06]; P=0.02) and LCX ostium (hazard ratio, 2.60 [95% CI, 1.11-6.07]; P=0.03) but not in the distal LM (hazard ratio, 0.81 [95% CI, 0.34-1.91]; P=0.63). Patients with stent underexpansion in both ostial LAD and LCX had a significantly higher rate of 5-year major adverse cardiac events than those with no or 1 underexpanded stent of either ostium (P<0.01).

CONCLUSIONS

Stent underexpansion in the LAD and LCX ostium was significantly associated with long-term outcomes in patients who underwent up-front 2-stenting for LM bifurcation stenosis.

Bifurcation PCI with a hybrid strategy with drug- eluting balloons versus a stepwise provisional two- stent strategy: Rationale and design of the hybrid DEB study

The optimal treatment strategy for coronary bifurcation lesions by percutaneous coronary intervention (PCI) is complex and remains a subject of debate. Current guidelines advise a stepwise provisional approach with optional two-stent strategy. However, a two-stent strategy, both upfront and stepwise provisional, is technically demanding. Therefore, there is increasing interest in the use of drug-eluting balloons (DEB) in bifurcation lesions, mainly after a provisional approach with unsatisfactory result of the side branch. Some small pilot studies already showed that the use of DEB in bifurcation lesions is safe and feasible. However, a randomized comparison of this hybrid DEB strategy with a two-stent strategy is currently lacking.

TRIAL DESIGN

The Hybrid DEB study is a prospective, multicenter, randomized controlled trial investigating noninferiority of a hybrid DEB approach, using a combination of a drug-eluting stent (DES) in the main vessel and DEB in the side branch, compared to stepwise provisional two-stent strategy in patients with true bifurcation lesions. A total of 500 patients with de novo true coronary bifurcation lesions, treated with a stepwise provisional approach and an unsatisfactory result of the side branch after main vessel stenting (≥ 70% stenosis and/or < thrombolysis in myocardial infarction III flow), will be randomized in a 1:1 ratio to receive either treatment with a DEB or with a DES in the side branch. The primary endpoint is a composite endpoint of the occurrence of all-cause death, periprocedural or spontaneous myocardial infarction and/or target vessel revascularization at the anticipated median 2-year follow-up.

CONCLUSION

The Hybrid DEB study will compare in a multicenter, randomized fashion a hybrid DEB approach with a stepwise provisional two-stent strategy in patients with true bifurcation lesions.

TRIAL REGISTRATION

ClinicalTrials.gov no. NCT05731687.

Multislice computerized tomography coronary angiography can be a comparable tool to intravascular ultrasound in evaluating "true" coronary artery bifurcations

Aim

Coronary bifurcation atherosclerosis depends on its angles, flow, and extensive branching. We investigate the ability of CT coronary angiography (CTCA) to determine atherosclerotic plaque characteristics of "true" bifurcation compared with intravascular ultrasound (IVUS) and the influence on side branch (SB) fate after percutaneous coronary intervention (PCI).

Methods and results

The study included 70 patients with 72 "true" bifurcations. Most of the bifurcations were in the left anterior descending-diagonal (Dg) territory [50 out of 72 (69.4%)]. Longitudinal plaque evaluation at the polygon of confluence [carina and 5 mm proximal and distal in the main branch (MB)] showed that carina side MB and SB plaque had occurred with the lowest incidence with fibro-lipid structure (115 ± 63 HU and 89 ± 73 HU, p < 0.001 for all). Bland-Altman analysis showed a discrepancy in measuring mainly the lumen area between CTCA and IVUS in proximal MB [lumen 5.10, 95% CI (95% confidence interval, 4.53-5.68) mm2, p < 0.001; vessel -1.42, 95% CI (-2.63 to -0.21) mm2, p = 0.023], carina MB [lumen 3.74, 95% CI (3.37-4.10) mm2, p < 0.001; vessel -0.48, 95% CI (-1.45 to 0.48) mm2, p = 0.322], and distal MB [lumen 4.72, 95% CI (4.27-5.18) mm2, p < 0.001; vessel 0.62, 95% CI (-0.53 to 1.77) mm2, p = 0.283]. A significant correlation existed between average plaque density on CTCA with a percentage of calcified plaque on IVUS tissue characterization (proximal r = 0.307/p = 0.024, carina 0.469/0.008, distal 0.339/0.024, minimal lumen diameter 0.318/0.020). Circumferential plaque in the proximal MB segment remained an independent predictor of SB compromise [OR 3.962 (95% CI 1.170-13.418)].

Conclusion

Detection and characterization of atherosclerotic plaque by CTCA in non-left main "true" coronary bifurcations can provide useful information about bifurcation anatomy and plaque distribution that can predict outcomes after provisional stenting, thus guiding the interventional strategy to bifurcation PCI.

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.

DES Selection for Left Main and Coronary Bifurcation Stenting

Coronary bifurcation lesions present a challenging lesion subset regarding procedural complexity and worse patient outcomes as compared to simple lesions. Drug eluting stents (DES), as the current standard of care for percutaneous myocardial revascularization, have tubular design and uniform diameter, and therefore, need to be subjected to a standardized set of procedural modifications, to optimally fit and reconstruct underlying bifurcation anatomy. Since contemporary DES have various design platforms, with diverse mechanical properties, we must be aware of the device's favorable characteristics and limitations, to ensure maximal procedural safety and success. This is especially true for bifurcation lesion stenting, during which device integrity will often be eventually tested by undergoing specific procedural steps, such as proximal balloon optimization, kissing-balloon inflations, or even intentional stent crushing. In this review we address the design characteristics of contemporary DES, their bifurcation-specific experimental testing data, and reported clinical results, in an attempt to provide relevant information and help in device selection for bifurcation stenting procedures.

Configuration of two-stent coronary bifurcation techniques in explanted beating hearts: the MOBBEM study

BACKGROUND

In patients with complex coronary bifurcation lesions undergoing percutaneous coronary intervention (PCI), various 2-stent techniques might be utilised. The Visible Heart Laboratories (VHL) offer an experimental environment where PCI results can be assessed by multimodality imaging.

AIMS

We aimed to assess the post-PCI stent configuration achieved by 2-stent techniques in the VHL and to evaluate the procedural factors associated with suboptimal results.

METHODS

Bifurcation PCI with 2-stent techniques, performed by expert operators in the VHL on explanted beating swine hearts, was studied. The adopted bifurcation PCI strategy and the specific procedural steps applied in each procedure were classified according to Main, Across, Distal, Side (MADS)-2 and to their adherence to the European Bifurcation Club (EBC) recommendations. Microcomputed tomography (micro-CT) was used to assess the post-PCI stent configuration. The primary endpoint was "suboptimal stent implantation", defined as a composite of stent underexpansion (<90%), side branch ostial area stenosis >50% and the gap between stents.

RESULTS

A total of 82 PCI with bifurcation stenting were assessed, comprised of 29 crush, 25 culotte, 28 T/T and small protrusion (TAP) techniques. Suboptimal stent implantation was observed in as many as 53.7% of the cases, regardless of baseline anatomy or the stenting strategy. However, less frequent use of the proximal optimisation technique (POT; p=0.015) and kissing balloon inflations (KBI; p=0.027) and no adherence to EBC recommendations (p=0.004, p multivariate=0.006) were significantly associated with the primary endpoint.

CONCLUSIONS

Commonly practised bifurcation 2-stent techniques may result in imperfect stent configurations. More frequent use of POT/KBI and adherence to expert recommendations might reduce the occurrence of post-PCI suboptimal stent configurations.

An Approach to Non-left Main Bifurcation Lesions: A Contemporary Review

Bifurcated anatomical locations in the arterial tree, such as coronary artery bifurcations, are prone to develop obstructive atherosclerotic lesions due to the pro-atherogenic low wall shear stress. The percutaneous treatment of bifurcation lesions is among the most challenging complex coronary interventions, including different multistep stenting strategies. Even though provisional side branch (SB) stenting is recommended as the primary approach in most cases, the debate continues between provisional SB and upfront two-stent strategies, particularly in complex bifurcations consisting of a significantly diseased SB that supplies a crucial myocardial territory. This review will highlight the importance of understanding the bifurcation philosophy and provide an individual algorithmic approach to find the optimal treatment strategy for each patient with a non-left main coronary bifurcation lesion. Considering the most recent scientific evidence, the advantages and disadvantages of each stenting technique and the role of intracoronary imaging to optimize bifurcation percutaneous coronary intervention outcomes will be discussed.

Percutaneous Treatment of Left Main Disease: A Review of Current Status

Percutaneous treatment of the left main coronary artery is one of the most challenging scenarios in interventional cardiology, due to the large portion of myocardium at risk the technical complexity of treating a complex bifurcation with large branches. Our aim is to provide un updated overview of the current indications for percutaneous treatment of the left main, the different techniques and the rationale underlying the choice for provisional versus upfront two-stent strategies, intravascular imaging and physiology guidance in the management of left main disease, and the role of mechanical support devices in complex high-risk PCI.

Comparing the clinical outcomes of single vs. systematic dual stenting strategies for unprotected left main bifurcation lesion: a systematic review and meta-analysis

INTRODUCTION

The optimal percutaneous coronary intervention (PCI) strategy for coronary left main (LM) bifurcation lesions remains controversial. This meta-analysis compared the medium and long-term follow-up clinical outcomes of single vs. systematic dual stenting strategies of LM bifurcation lesions.

METHODS

We systematically identified studies published within 5 years comparing single vs. systematic double stenting strategies for LM bifurcation lesions. The primary endpoint was medium-term (1 year) and long-term (at least 3 years) all-cause death. Secondary outcomes included major adverse cardiovascular events (MACEs), target lesion revascularization (TLR), overall occurrence of stent thrombosis (ST), cardiovascular (CV) mortality, and myocardial infarction (MI).

RESULTS

Two randomized controlled trials and nine observational studies with 7,318 patients were included in this meta-analysis. In terms of the medium-term follow-up clinical outcomes, our pooled analysis showed that use of the systematic dual stenting strategy was associated with a lower ST risk (odds ratio [OR] = 0.43, 95% confidence interval [CI]: 0.20-0.89, P = 0.02) and cardiac death risk (OR = 0.43, 95% CI: 0.21-0.89, P = 0.02) compared to the single stenting strategy; there was no significant difference between the two strategies regarding rates of all-cause death, MACE, TLR, and MI. Patients with long-term follow-up showed comparable observed clinical outcomes between the two strategies. Most importantly, for patients with true LM bifurcation, the risk of all-cause death, ST, and CV mortality following the systematic dual stenting strategy was significantly lower than the single stenting strategy.

CONCLUSIONS

For patients with LM bifurcation lesions, both the systematic dual stenting strategy and single stenting strategy demonstrated comparable results in terms of all-cause mortality during medium-term and long-term follow-up. However, the systematic dual stenting strategy showed a tendency towards lower incidence of ST and CV mortality compared to the single stenting strategy during medium-term follow-up. Consequently, the systematic dual stenting strategy yielded superior clinical outcomes for patients with LM bifurcation lesions.

Left Main Percutaneous Coronary Revascularization

Left main (LM) coronary artery disease accounts for approximately 4-6% of all percutaneous coronary interventions (PCIs). There has been mounting evidence indicating the non-inferiority of LM PCI as a revascularization option, particularly for those with a low SYNTAX score. The EXCEL and NOBEL trials have shaped current guidelines. The European Society of Cardiology assigned a class 2a (level of evidence B) for isolated LM disease involving the shaft and ostium and a class IIb (level of evidence B) for isolated LM disease involving the bifurcation or additional two- or three-vessel disease and a SYNTAX score <32. However, data on the use of a single stent or an upfront two-stent strategy for distal LM disease are conflicting, wherein the EBC Main trial reported similar outcomes with a stepwise provisional approach and the DKCRUSH-V trial reported better outcomes with an upfront two-stent strategy using the 'double-kissing' crush technique. Although several studies have noted better immediate results with image-guided PCI, there are few data on outcomes in LM disease specifically. In fact, the uptake of imaging in the aforementioned landmark trials was only 40%. More importantly, the role of mechanical circulatory support (MCS) has been less well studied in LM PCI. Indiscriminate use of MCS for LM PCI has been noted in clinical practice. Trials evaluating the benefit of MCS in high-risk PCI demonstrated no benefit. This review highlights contemporary trials as they apply to current practice in LM PCI.

Late stent thrombosis as a complication of T and small protrusion bifurcation stenting: a case report

Background

A case of stent thrombosis as a complication of coronary bifurcation stenting is described. We review potential complications of bifurcation stenting and established guidelines.

Case summary

A 64-year-old man presented with a non-ST segment elevation myocardial infarction. High-sensitivity troponin I peaked at 99 000 ng/L (normal <5). He previously had coronary stenting for stable angina when residing in another country 2 years previously. Coronary angiography revealed no significant stenosis with TIMI 3 flow in all vessels. Cardiac magnetic resonance imaging demonstrated a left anterior descending artery (LAD) territory regional motion abnormality, late gadolinium enhancement consistent with recent infarction, and a left ventricular apical thrombus. Repeat angiography and intravascular ultrasound (IVUS) confirmed bifurcation stenting at the junction of the LAD and second diagonal (D2) with protrusion of several millimetres of the uncrushed proximal segment of the D2 stent in the LAD vessel lumen. There was under-expansion of the LAD stent in the mid-vessel and stent malapposition in the proximal LAD, extending into the distal left main stem coronary artery and involving the ostium of the left circumflex coronary artery. Percutaneous balloon angioplasty was performed along the length of the stent, including an internal crush of the D2 stent. Coronary angiography confirmed a uniform expansion of the stented segments and TIMI 3 flow. Final IVUS confirmed full stent expansion and apposition.

Discussion

This case highlights the importance of provisional stenting as a default strategy and familiarity with procedural steps in bifurcation stenting. Furthermore, it emphasizes the benefit of intravascular imaging for lesion characterization and stent optimization.

Stepwise provisional versus systematic culotte for stenting of true coronary bifurcation lesions: five-year follow-up of the multicentre randomised EBC TWO Trial

BACKGROUND

The multicentre European Bifurcation Club Trial (EBC TWO) showed no significant differences in 12-month clinical outcomes between patients randomised to a provisional stenting strategy or systematic culotte stenting in non-left main true bifurcations.

AIMS

This study aimed to investigate the 5-year clinical results of the EBC TWO Trial.

METHODS

A total of 200 patients undergoing stent implantation for non-left main bifurcation lesions were recruited into EBC TWO. Inclusion criteria required a side branch diameter ≥2.5 mm and side branch lesion length >5 mm. Five-year follow-up was completed for 197 patients. The primary endpoint was the composite of all-cause mortality, myocardial infarction, or target vessel revascularisation.

RESULTS

The mean side branch stent diameter was 2.7±0.3 mm and mean side branch lesion length was 10.3±7.2 mm. At 5-year follow-up, the primary endpoint occurred in 18.4% of provisional and 23.7% of systematic culotte patients (hazard ratio [HR] 0.75, 95% confidence interval [CI]: 0.41-1.38). No significant differences were identified individually for all-cause mortality (7.8% vs 7.2%, HR 1.11, 95% CI: 0.40-3.05), myocardial infarction (8.7% vs 13.4%, HR 0.64, 95% CI: 0.27-1.50) or target vessel revascularisation (6.8% vs 9.3%, HR 1.12, 95% CI: 0.37-3.34). Stent thrombosis rates were also similar (1.9% vs 3.1%, HR 0.63, 95% CI: 0.11-3.75). There was no significant interaction between the extent of side branch disease and the primary outcome (p=0.34).

CONCLUSIONS

In large non-left main true bifurcation lesions, the use of a systematic culotte strategy showed no benefit over provisional stenting for the composite outcome of all-cause mortality, myocardial infarction, or target vessel revascularisation at 5 years. The stepwise provisional approach may be considered preferable for the majority of true coronary bifurcation lesions.

CLINICALTRIALS

gov: NCT01560455.

The 17th expert consensus document of the European Bifurcation Club - techniques to preserve access to the side branch during stepwise provisional stenting

Provisional stenting has become the default technique for the treatment of most coronary bifurcation lesions. However, the side branch (SB) can become compromised after main vessel (MV) stenting and restoring SB patency can be difficult in challenging anatomies. Angiographic and intracoronary imaging criteria can predict the risk of side branch closure and may encourage use of side branch protection strategies. These protective approaches provide strategies to avoid SB closure or overcome compromise following MV stenting, minimising periprocedural injury. In this article, we analyse the strategies of SB preservation discussed and developed during the most recent European Bifurcation Club (EBC) meetings.

The Degree of Stent Apposition Measured by Stent Enhancement at the Level of the Side Branch as a Novel Predictor of Procedural Success in Left Main PCI

BACKGROUND

Stent enhancement techniques allow adequate visualization of stent deformation or incomplete stent expansion at the ostium of the side branch. Measuring the stent enhancement side branch length (SESBL) could reflect procedural success in terms of optimal stent expansion and apposition with better long-term outcomes. A longer SESBL may reflect a better stent apposition at the polygon of confluence and at the side branch (SB) ostium.

METHODS

We evaluated 162 patients receiving the left main (LM) provisional one-stent technique and measured the SESBL, dividing them into two groups: SESBL≤ 2.0 mm and SESBL > 2.0 mm.

RESULTS

The mean SESBL was 2.0 ± 1.2 mm. More than half of the bifurcations had both main and side branch lesions (Medina 1-1-1) (84 patients, 51.9%) and the length of the SB disease was 5.2 ±1.8 mm. Kissing balloon inflation (KBI) was performed in 49 patients (30.2%). During follow-up (12 months), there was a significantly higher rate of cardiac death in the SESBL ≤ 2.0 mm group (p = 0.02) but no significant difference in all major adverse cardiovascular events (MACEs) (p = 0.7). KBI did not influence the outcomes (p = 0.3).

CONCLUSION

Suboptimal SESBL is positively correlated with worse outcomes and SB compromise. This novel sign could aid the LM operator to assess the level of stent expansion at the ostium of the SB in the absence of intracoronary imaging.

Dynamic assessment of the left main-left circumflex bending angle: Implications for ostial left circumflex artery in-stent restenosis after successful two-stent PCI

BACKGROUND

Two-stent techniques for percutaneous coronary intervention (PCI) on left main (LM) bifurcation (LMB) lesions are associated with an increased risk of in-stent restenosis (ISR) at left circumflex artery (LCx) ostium but the underlying mechanisms are incompletely understood. This study sought to investigate the association between cyclic change of LM-LCx bending angle (BA_LM-LCx) and the risk of ostial LCx ISR following two-stent techniques.

METHODS

In a retrospective cohort of patients undergoing two-stent PCI for LMB lesions, BA_LM-LCx and distal bifurcation angle (DBA) were computed with 3-dimensional angiographic reconstruction. The analysis was performed both at end-diastole and end-systole, and the angulation change throughout the cardiac cycle was defined as the cardiac motion-induced angulation change (∆_CAngle).

RESULTS

A total of 101 patients were included. The mean pre-procedural BA_LM-LCx was 66.8 ± 16.1° at end-diastole and 54.1 ± 13.3° at end-systole with a range of 13.0 ± 7.7°. Pre-procedural ∆_CBA_LM-LCx > 16.4° was the most relevant predictor of ostial LCx ISR (adjusted OR 11.58, 95% CI 4.04-33.19; p < 0.001). Post-procedural ∆_CBA_LM-LCx > 9.8° and stent-induced diastolic BA_LM-LCx change > 11.6° were also related with ostial LCx ISR. DBA was positively correlated with BA_LM-LCx and showed a weaker association of pre-procedural ∆_CDBA > 14.5° with ostial LCx ISR (adjusted OR 6.87, 95% CI 2.57-18.37; p < 0.001).

CONCLUSIONS

Three-dimensional angiographic bending angle is a feasible and reproducible novel method for LMB angulation measurement. A large pre-procedural cyclic change of BA_LM-LCx was associated with an increased risk of ostial LCx ISR following two-stent techniques.

Management of failed stenting of the unprotected left main coronary artery

Percutaneous coronary intervention (PCI) is increasingly accepted as treatment for unprotected left main coronary artery (ULMCA) disease especially in those patients who are unsuitable for cardiac surgery. Treatment of any stent failure is associated with increased complexity and worse clinical outcomes when compared with de novo lesion revascularization. Intracoronary imaging has provided new insight into mechanisms of stent failure and treatment options have developed considerably over the last decade. There is paucity of evidence on the management strategy for stent failure in the specific setting of ULMCA. Treating any left main with PCI requires careful consideration and consequently treatment of failed stents in ULMCA is complex and provides unique challenges. Consequently, we provide an overview of ULMCA stent failure, proposing a tailored algorithm to guide best management and decision in daily clinical practice, with a special focus on intracoronary imaging characterization of causal mechanisms and specific technical and procedural considerations.

Post-procedure micro-CT analyses of coronary artery stenting in left main vessels of reanimated and perfusion-fixed human hearts

BACKGROUND

Percutaneous coronary interventions (PCIs) within left main coronary arteries are high-risk procedures that require optimization of interactions between stent(s) and diseased vessels. Optical Coherence Tomography (OCT) is a widely accepted tool that enhances physicians' ability to assess proper stent appositions during clinical procedures. The primary aim of this study was to develop complementary post-procedure imaging methodologies to better assess and interpret outcomes of left main PCI procedures, utilizing both reanimated and perfusion-fixed human hearts.

METHODS

PCIs were performed while obtaining OCT scans within the left main anatomies of six human hearts. Subsequently, each heart was scanned with a micro-CT scanner with optimized parameters to achieve resolutions up to 20 µm. Scans were reconstructed and imported into a DICOM segmentation software to generate computational models of implanted stents and associated coronary vessels. 2D images from OCT that were obtained during PCIs were compared to the 3D models generated from micro-CT reconstructions. In addition, the 3D models were utilized to create virtual reality scenes and enlarged 3D prints for development of "mixed reality" tools relative to bifurcation stenting within human left main coronary arteries.

RESULTS

We developed reproducible methodologies for post-implant analyses of coronary artery stenting procedures. In addition, we generated high-resolution 3D computational models, with ~ 20-micron resolutions, of PCIs performed within reanimated and perfusion-fixed heart specimens.

CONCLUSIONS

Generated computational models of left main PCIs performed in isolated human hearts can be used to obtain detailed measurements that provide further clinical insights on procedural outcomes. The 3D models from these procedures are useful for generating virtual reality scenes and 3D prints for physician training and education.

OCT Guidance in Bifurcation Percutaneous Coronary Intervention

Coronary bifurcation is defined by the European Bifurcation Consensus as a coronary artery stenosis adjacent to the origin of a significant side branch. Its anatomy is composed of 3 different segments: proximal main vessel, distal main vessel and side branch. Coronary artery bifurcation lesions are encountered in approximately 15-20% of all percutaneous coronary interventions and constitute a complex subgroup of lesions characterized by lower procedural success rates and higher rates of adverse outcomes. In recent years, a growing focus in the European and Japanese bifurcation club meetings has been the emerging role of intravascular imaging, in guiding successful bifurcation percutaneous coronary interventions (PCI). In this review we will present the main ways optical coherence tomography (OCT) can be used to improve outcomes during bifurcation PCI.

Stent Thrombosis and Restenosis with Contemporary Drug-Eluting Stents: Predictors and Current Evidence

Iterations in stent technologies, advances in pharmacotherapy, and awareness of the implications of implantation techniques have markedly reduced the risk of stent failure, both in the form of stent thrombosis (ST) and in-stent restenosis (ISR). However, given the number of percutaneous coronary interventions (PCI) performed worldwide every year, ST and ISR, albeit occurring at a fairly low rate, represent a public health problem even with contemporary DES platforms. The understanding of mechanisms and risk factors for these two PCI complications has been of fundamental importance for the parallel evolution of stent technologies. Risk factors associated with ST and ISR are usually divided into patient-, lesion-, device- and procedure-related. A number of studies have shown how certain risk factors are related to early (1 month) versus late/very late ST (between 1 month and 1 year and >1 year, respectively). However, more research is required to conclusively show the role of time-dependence of risk factors also in the incidence of ISR (early [1 year] or late [>1 year]). A thorough risk assessment is required due to the complex etiology of ST and ISR. The most effective strategy to treat ST and ISR is still to prevent them; hence, it is crucial to identify patient-, lesion-, device- and procedure-related predictors.