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

The influence of reverse flow within side branches on plaque formation relative to coronary bifurcation angles

The occurrence of atherosclerotic lesions in the coronary bifurcation tends to progress confined to specific areas depending on blood flow patterns. We conducted a numerical investigation into the three-dimensional bifurcation flow of the coronary artery, focusing on a side branch vessel branching off at a specified bifurcation angle. This study examined the impact of the bifurcation angle on flow characteristics around the bifurcation region, including wall shear stress, static pressure, the size of the reverse flow zone, and the flow rate distribution to the side branch vessel. Unsteady pulsatile flow has been considered at Re = 300 assuming blood as a Newtonian fluid. Our numerical results indicate that as the bifurcation angle increases, the pressure drop between the inlet and outlet increases, while the flow rate to the side branch vessel decreases. Additionally, in our study, a reverse flow zone near the outer wall of the side branch was observed, and it was found that the reverse flow becomes stronger as the bifurcation angle increases due to the lower momentum of blood near the outer wall and the central part of the side branch vessel. The height of reverse flow zone of the side branch rapidly increases as the bifurcation angle increases up to about 60 degrees and then mildly saturates as the bifurcation angle increases. Flow stagnation in the reverse flow zone of the side branch may promote platelet aggregation and lipid deposition, accelerating the formation of atherosclerotic plaques.

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.

State-of-the-art percutaneous coronary intervention for left main coronary artery disease in Japan

Percutaneous coronary intervention for left main coronary artery disease (LM-PCI) represents a high-risk yet life-saving procedure that has evolved significantly over the years. This review outlines the current state-of-the-art practices for LM-PCI in Japan in detail, emphasizing the integration of coronary physiology and intracoronary imaging alongside with evidence-based standardized technique using latest drug-eluting stents. These advancements enable precise lesion assessment, stent sizing, and optimal deployment, thereby enhancing procedural safety and efficacy. Despite discrepancies between current guidelines favoring coronary artery bypass grafting and real-world practice trends towards increased LM-PCI adoption, particularly in elderly populations with multiple comorbidities, careful patient selection and procedural planning are critical. Future perspectives include further refining LM-PCI through conducting randomized controlled trials integrating advanced techniques and addressing the issue of ostial left circumflex lesions and nationwide standardization of medical care for LM disease.

Contemporary Use of Coronary Physiology in Cardiology

Coronary angiography has a limited ability to predict the functional significance of intermediate coronary lesions. Hence, physiological assessment of coronary lesions, via fractional flow reserve (FFR) or instantaneous wave-free ratio (iFR), has been introduced to determine their functional significance. An accumulating body of evidence has consolidated the role of physiology-guided revascularization, particularly among patients with stable ischemic heart disease. The use of FFR or iFR to guide decision-making in patients with stable ischemic heart disease and intermediate coronary lesions received a class I recommendation from major societal guidelines. Nevertheless, the role of coronary physiology testing is less clear among certain patients' groups, including patients with serial coronary lesions, acute coronary syndromes, aortic stenosis, heart failure, as well as post-percutaneous coronary interventions. In this review, we aimed to discuss the utility and clinical evidence of coronary physiology (mainly FFR and iFR), with emphasis on those specific patient groups.

Practical Application of Coronary Physiologic Assessment: Asia-Pacific Expert Consensus Document: Part 2

Coronary physiologic assessment is performed to measure coronary pressure, flow, and resistance or their surrogates to enable the selection of appropriate management strategy and its optimization for patients with coronary artery disease. The value of physiologic assessment is supported by a large body of clinical data that has led to major recommendations in all practice guidelines. This expert consensus document aims to convey practical and balanced recommendations and future perspectives for coronary physiologic assessment for physicians and patients in the Asia-Pacific region, based on updated information in the field that includes both wire- and image-based physiologic assessment. This is Part 2 of the whole consensus document, which provides theoretical and practical information on physiologic indexes for specific clinical conditions and patient statuses.

Left main bifurcation stenting: impact of residual ischaemia on cardiovascular mortality

AIMS

The present study sought to determine the rate and prognostic implications of post-procedural physiologically significant residual ischemia according to Murray law-based quantitative flow ratio (μQFR) after left main (LM) bifurcation percutaneous coronary intervention (PCI).

METHODS AND RESULTS

Consecutive patients undergoing LM bifurcation stenting at a large tertiary care center between January 2014 and December 2016 with available post-PCI μQFR were included. Physiologically significant residual ischemia was defined by post-PCI μQFR values ≤0.80 in the left anterior descending (LAD) or left circumflex artery (LCX). The primary outcome was 3-year cardiovascular death. The major secondary outcome was 3-year bifurcation-oriented composite endpoint (BOCE). Among 1170 included patients with analyzable post-PCI μQFR, 155 (13.2%) had residual ischemia in either LAD or LCX. Patients with vs. those without residual ischemia had a higher risk of 3-year cardiovascular mortality [5.4% vs. 1.3%; adjusted hazard ratio (HR) 3.20, 95% confidence interval (CI): 1.16-8.80]. The 3-year risk of BOCE was significantly higher in the residual ischemia group (17.8% vs. 5.8%; adjusted HR 2.79, 95% CI: 1.68-4.64), driven by higher incidence of the composite of cardiovascular death and target bifurcation-related myocardial infarction (14.0% vs. 3.3%; adjusted HR 4.06, 95% CI: 2.22-7.42). A significant, inverse association was observed between continuous post-PCI μQFR and the risk of clinical outcomes (per 0.1 μQFR decrease, HR of cardiovascular death 1.27, 95% CI: 1.00-1.62; HR of BOCE 1.29, 95% CI: 1.14-1.47).

CONCLUSION

After angiographically successful LM bifurcation PCI, residual ischemia assessed by μQFR was identified in 13.2% of patients and was associated with higher risk of 3-year cardiovascular death, indicating the superior prognostic value of post-PCI physiological assessment.

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.

Provisional Strategy for Left Main Stem Bifurcation Disease: A State-of-the-Art Review of Technique and Outcomes

Left main coronary artery (LMA) disease jeopardizes a large area of myocardium and increases the risk of major adverse cardiovascular events. LMCA disease is found in 5% to 7% of all diagnostic coronary angiographies, and more than 80% of the patients enrolled in recent large randomized controlled left main trials had distal left main bifurcation or trifurcation disease. Emerging clinical evidence from prospective all-comer registries and randomized trials has provided a solid basis for percutaneous coronary intervention as a treatment option in selected patients with unprotected LMCA disease; however, to date, no uniform recommendations as to optimal stenting strategy for LMCA bifurcation lesions exist. This review provides an overview of provisional stenting technique and escalation to 2-stent strategies in LMCA bifurcation lesions. Data from randomized controlled trials and registries are reviewed. Technical characteristics of optimal provisional LMCA stenting technique and angiographic and intravascular determinants of escalation are also summarized.

Clinical Characteristics and Outcomes following Percutaneous Coronary Intervention in Unprotected Left Main Disease: A Single-Center Study

Background: Hemodynamically significant unprotected left main (LM) coronary artery disease is a high-risk clinical condition because of the large area of myocardium at risk, and it requires prompt revascularization. Percutaneous coronary intervention (PCI) is an appropriate alternative to coronary artery bypass grafting (CABG) for revascularization of unprotected LM disease in patients with low-to-intermediate anatomic complexity or when the patient refuses CABG after adequate counseling by the heart team. Methods: We retrospectively evaluated 201 patients receiving left main (LM) provisional one-stent or two-stent procedures, and we assessed the clinical characteristics and outcomes of patients undergoing unprotected LM PCI. Results: The mean age was 66.5 ± 9.9 years, and 72% were male. The majority of the subjects presented several cardiovascular risk factors, among which arterial hypertension (179 patients, 89.5%) and dyslipidemia (173 patients, 86.5%) were the most frequent. Out of all patients, 162 (81.8%) underwent revascularization by using the one-stent technique, while the two-stent technique was used in 36 patients (18.2%). The median value of fractional flow reserve (FFR) of the side branch was 0.9 [0.85–0.95], and 135 patients (67.1%) showed a value of FFR > 0.8. One hundred nine patients (54.2%) had a stent enhancement side branch length (SESBL) > 2, with median values of 2.5 mm2 [2.1–3]. Regarding angiographic parameters, the LM area as assessed by intravascular ultrasound (IVUS) or optical coherence tomography (OCT) and the grade of stenosis as assessed by quantitative coronary angiography (QCA) were similar between groups. However, patients who required revascularization by using the two-stent technique presented more frequently with intermediate rather than low SYNTAX scores (69.4% vs. 28.4%, p < 0.0001). Also, the same group required kissing balloon inflation (KBI) more frequently (69.4% vs. 30%, p < 0.001). There were no differences regarding the success of revascularization between the use of the one-stent or two-stent technique. FFR was able to predict a SESBL > 2 mm. The cut-off value for FFR to afford the highest degree of sensitivity (74.5%) and specificity (47%) for a SESBL > 2 was >0.86, indicating a moderate accuracy (AUC = 0.61, 95% CI 0.525–0.690, p = 0.036). Conclusions: Unprotected left main PCI is a safe and effective revascularization option amongst a complex and morbid population. There were no differences regarding the success of revascularization between the use of the one-stent or two-stent technique, and there was no significant impact of KBI on side branch FFR measurements but lower side branch FFR values were correlated with angiographic side branch compromise.

Long-term prognostic value of Murray law-based quantitative flow ratio in jailed left circumflex coronary artery after left main crossover stenting

We aimed to evaluate the impact of new Murray law-based QFR of jailed left circumflex coronary artery (LCx) on long-term clinical outcomes after left main coronary artery (LM) simple crossover stenting. 164 patients who underwent LM-to-left anterior descending coronary artery simple crossover stenting and had appropriate angiographic view of LCx for QFR computation were enrolled. The primary clinical outcome was the 5-year target lesion failure (TLF), defined as a composite of cardiac death, a target vessel myocardial infarction or target lesion repeat revascularization. The mean QFR of the LCx after LM stent implantation was 0.88 ± 0.09, and 29 patients (17.7%) had a low QFR (< 0.80), which was significantly associated with a higher 5-year rate of TLF when compared with the high QFR group (27.6% vs. 6.7%; HR: 4.235; 95% CI 1.21-14.95; p = 0.0015). The 5-year LCx ostium-related TLR rate in the low QFR group was also higher (17.2% vs. 3.0% in the high QFR group; HR: 6.07, 95% CI 1.63-22.59, p = 0.002). In a multivariate Cox regression analysis, a low QFR in the LCx after LM stenting was an independent predictor of the 5-year TLF rate (HR: 3.21, 95% CI 1.21-8.53; p = 0.019). ROC analysis showed that QFR a negative predictive value (NPV) of 89.6% ([AUC] 0.73, 95% CI 0.58-0.88, p < 0.05), the cutoff point is 0.85. The patients with a low QFR (< 0.80) in jailed LCX after LM simple crossover stenting had worse 5-year outcomes than those with a high QFR. Conversely, a QFR ≥ 0.85 of jailed LCx could serve as a good predictor of low risk of adverse outcome in LCx ostium. The QFR computation of the jailed LCx may be helpful to determine whether an additional procedure is required for the jailed side branch.

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting for Revascularization of Left Main Coronary Artery Disease

Owing to a large-jeopardized myocardium, left main coronary artery disease (LMCAD) represents the substantial high-risk anatomical subset of obstructive coronary artery disease. For several decades, coronary artery bypass grafting (CABG) has been the "gold standard" treatment for LMCAD. Along with advances in CABG, percutaneous coronary intervention (PCI) has also dramatically evolved over time in conjunction with advances in the stent or device technology, adjunct pharmacotherapy, accumulated experiences, and practice changes, establishing its position as a safe, reasonable treatment option for such a complex disease. Until recently, several randomized clinical trials, meta-analyses, and observational registries comparing PCI and CABG for LMCAD have shown comparable long-term survival with tradeoffs between early and late risk-benefit of each treatment. Despite this, there are still several unmet issues for revascularization strategy and management for LMCAD. This review article summarized updated knowledge on evolution and clinical evidence on the treatment of LMCAD, with a focus on the comparison of state-of-the-art PCI with CABG.

Jailed pressure wire technique for coronary bifurcation lesions: structural damage and clinical outcomes

INTRODUCTION AND OBJECTIVES

The use of a pressure wire as a jailed wire to evaluate side branch results during provisional stenting seems feasible. However, safety concerns exist due to the mechanical damage of the wire and the lack of prospective data evaluating the prognosis of patients treated using this technique. This study sought to evaluate the structural damage of the pressure wire in patients treated using the jailed pressure wire technique and to assess mid-term clinical outcomes.

METHODS

We enrolled 99 patients with single bifurcation lesions and provisional stenting as the strategy of choice. A jailed pressure wire was used to guide side branch intervention according to the instantaneous wave-free ratio (iFR). A total of 114 patients and the respective nonpolymer-coated jailed wires were used as historical controls. Guidewire damage was evaluated by stereomicroscopy. The primary endpoint was significant microscopic damage. Major adverse cardiac events were evaluated at 2-year follow-up.

RESULTS

Significant microscopic damage was more frequent in pressure wires than in nonpolymer-coated wires (53.5% vs 22.8%, P<.001). There were no fractures in either group. There were fewer side branch interventions in the pressure wire group (postdilation/kissing balloon, 32.3% vs 56.1%, P=.001; stenting, 0.0% vs 2.6%, P=.104). The 2-year rate of major adverse cardiac events was similar between the 2 groups (HR_adj, 0.42; 95%CI, 0.10-1.73; P=.229).

CONCLUSIONS

Pressure wires were less resistant to jailing than conventional nonpolymer-coated wires. Patients treated with iFR-guided provisional stenting required fewer side branch interventions but had similar 2-year clinical outcomes than patients treated with the angiography-guided technique.

Left Main Disease

Traditionally, the treatment of left main coronary artery disease is recommended coronary artery bypass grafting because of its superior long-term outcomes compared with medical treatment and plain old balloon angioplasty. However, improvement of percutaneous coronary intervention technique and introduction of drug-eluting stent led to change of treatment strategy of left main coronary artery disease through cumulative data for revascularization that based on clinical evidence.

Left Main Coronary Artery Disease-Current Management and Future Perspectives

Due to its anatomical features, patients with an obstruction of the left main coronary artery (LMCA) have an increased risk of death. For years, coronary artery bypass grafting (CABG) has been considered as a gold standard for revascularization. However, notable advancements in the field of percutaneous coronary intervention (PCI) led to its acknowledgement as an important treatment alternative, especially in patients with low and intermediate anatomical complexity. Although recent years brought several random clinical trials that investigated the safety and efficacy of the percutaneous approach in LMCA, there are still uncertainties regarding optimal revascularization strategies. In this paper, we provide a comprehensive review of state-of-the-art diagnostic and treatment methods of LMCA disease, focusing on percutaneous methods.

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

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

Functional comparison of different jailed balloon techniques in treating non-left main coronary bifurcation lesions

BACKGROUND

There is a paucity of data comparing functional difference between active jailed balloon technique (A-JBT) and conventional jailed balloon technique (C-JBT) in treating non-left main coronary bifurcation lesions (CBLs).

METHODS

In this retrospective cohort study, we consecutively enrolled 232 patients with non-left main CBLs who underwent percutaneous coronary intervention (PCI) using JBTs between January 2018 and March 2019. Among them, 191 patients entered the final analysis with 12-months angiographic follow-up. We stratified patients into A-JBT group (130 patients) and C-JBT group (61 patients). The functional analysis by Murray law-based quantitative flow ratio (μQFR) and Seattleanginaquestionnaire (SAQ) were performed to compare the two techniques.

RESULTS

Compared with C-JBT group, A-JBT group observed a lower abrupt (0.8% vs. 11.1%, p = 0.002) and final SB occlusion (0 vs. 7.9%, p = 0.005). Meanwhile, A-JBT group had a significantly higher μQFR of side branch (SB) both post-PCI and 12-months follow-up (median [interquartile range (IQR)]: 0.91 (0.86-0.96) vs. 0.82 (0.69-0.92), p < 0.001; median [IQR]: 0.95 (0.89-0.98) vs. 0.85 (0.74-0.93), p < 0.001) than C-JBT group. Besides, A-JBT group gained a μQFR improvement at follow-up period compared with post-PCI data (median [IQR]: 0.95 [0.89-0.98] vs. 0.91[0.86-0.96] of SB, p < 0.001) and a higher SAQ scores at 12-months follow-up compared with C-JBT group (p < 0.001).

CONCLUSIONS

Compared with C-JBT, A-JBT provided excellent SB protection during MV stenting and improved the SB functional blood flow as well as the angina relief even after 12 months.

Percutaneous Coronary Intervention for Left Main Coronary Artery Disease: Present Status and Future Perspectives

For several decades, coronary artery bypass grafting has been regarded as the standard choice of revascularization for significant left main coronary artery (LMCA) disease. However, in conjunction with remarkable advancement of device technology and adjunctive pharmacology, percutaneous coronary intervention (PCI) offers a more expeditious approach with rapid recovery and is a safe and effective alternative in appropriately selected patients with LMCA disease. Several landmark randomized clinical trials showed that PCI with drug-eluting stents for LMCA disease is a safe option with similar long-term survival rates to coronary artery bypass grafting surgery, especially in those with low and intermediate anatomic risk. Although it is expected that the updated evidence from recent randomized clinical trials will determine the next guidelines for the foreseeable future, there are still unresolved and unmet issues of LMCA revascularization and PCI strategy. This paper provides a comprehensive review on the evolution and an update on the management of LMCA disease.

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

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

Side Branch is the Main Determinant Factor of Bifurcation Lesion Complexity: Critical Review with a Proposal Based on Single-centre Experience

Although bifurcation stenting can be often managed with a simple provisional approach, in some settings, more complex techniques are appropriate. Based on our clinical experience and on data from literature, we propose a simple algorithm that may assist in selecting cases for elective double stenting. We found that, when the side branch is of adequate dimensions and affected by significant disease (longer than 10 mm and/or with presence of ostial calcifications), double stenting is associated with a lower incidence of adverse events, compared with provisional stenting.

Improving PCI Outcomes Using Postprocedural Physiology and Intravascular Imaging

Although clinical outcomes after percutaneous coronary intervention (PCI) are improving, the long-term risk for target vessel failure remains concerning. Although the application of intravascular imaging and physiological indexes significantly improves outcomes, their routine use in practice remains limited. Nevertheless, merely using these modalities is not enough, and to truly improve patient outcomes, optimal intravascular dimensions with minimal vascular injury should be targeted. When assessing post-PCI results using either type of physiological or imaging technology, a broad spectrum of stent- and vessel-related anomalies can be expected. As not all of these issues warrant treatment, a profound knowledge of what to expect and how to recognize and when to treat these intraluminal problems is needed. Additionally, promising new modalities such as angiography-derived coronary physiology and hybrid imaging catheters are becoming available. The authors provide an overview of the currently available tools and techniques to define suboptimal PCI and when to apply these technologies to improve outcomes.

Predictors and 3-year outcomes of compromised left circumflex coronary artery after left main crossover stenting

BACKGROUND

There are few predictors of decreased fractional flow reserve (FFR) in the left circumflex coronary artery (LCx) after left main (LM) crossover stenting.

OBJECTIVES

We aimed to determine the predictors for low FFR at LCx and possible treatment strategies for compromised LCx, together with their long-term outcomes.

METHODS

Altogether, 563 patients who met the inclusion criteria were admitted to our hospital from February 2015 to November 2020 with significant distal LM bifurcation lesions. They underwent single-stent crossover percutaneous coronary intervention (PCI) under intravascular ultrasound (IVUS) guidance with further LCx intervention based on the measured FFR.

RESULTS

The patients showed significant angiographic LCx ostial affection post-LM stenting, but only 116 (20.6%) patients had FFR < 0.8. The three-year composite major adverse cardiac events (MACE) rates were comparable between the high and low FFR groups (16.8% vs. 15.5; p = 0.744). In a multivariate analysis, low FFR at the LCx was associated with post-stenting minimal luminal area (MLA) of LCx (odds ratio [OR]: 0.032, p < .001), post-stenting LCx plaque burden (OR: 1.166, p < .001), poststenting LM MLA (OR: 0.821, p = .038), and prestenting LCx MLA (OR: 0.371, p = .044). In the low FFR group, those with compromised LCx managed with drug-eluting balloon had the lowest three-year MACE rate (8.1%), as compared to either those undergoing kissing balloon inflation (KBI) (17.5%) or stenting (20.5%) (p = 0.299).

CONCLUSION

Unnecessary LCx interventions can be avoided with FFR-guided LCx intervention. Poststenting MLA and plaque burden of the LCx, and main vessel stent length are poststenting predictors of low FFR.

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

Background

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

Objectives

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

Methods

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

Results

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

Conclusions

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

Difference in basic concept of coronary bifurcation intervention between Korea and Japan. Insight from questionnaire in experts of Korean and Japanese bifurcation clubs

The coronary bifurcation intervention varies among countries due to the differences in assessment of lesion severity and treatment devices. We sought to clarify the difference in basic strategy between South Korea and Japan. A total of 19 and 32 experts from Korean (KBC) and Japanese Bifurcation Clubs (JBC), respectively, answered a survey questionnaire concerning their usual procedure of coronary bifurcation intervention. JBC experts performed less two-stent deployment in the left main (LM) bifurcation compared to KBC experts (JBC vs. KBC: median, 1–10% vs. 21–30%, p < 0.0001) instead of higher performance of side branch dilation after cross-over stenting in both LM (60% vs. 21%, p = 0.001) and non-LM bifurcations (30% vs. 5%, p = 0.037). KBC experts more frequently performed proximal optimization technique (POT) in non-LM bifurcation (41–60% vs. 81–99%, p = 0.028) and re-POT in both LM (1–20% vs. 81–99%, p = 0.017) and non-LM bifurcations (1–20% vs. 81–99%, p = 0.0003). JBC experts more frequently performed imaging-guided percutaneous coronary intervention, whereas KBC experts more often used a pressure wire to assess side branch ischemia. JBC experts used a rotablator more aggressively under the guidance of optical coherence tomography. We clarified the difference in the basic strategy of coronary bifurcation intervention between South Korea and Japan for better understanding the trend in each country.

Asia Pacific consensus document on coronary bifurcation interventions

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

Percutaneous management of coronary bifurcation lesions: current perspective

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Opportunities and challenges of implementing computed tomography fractional flow reserve into clinical practice

CT-derived fractional flow reserve (CT-FFR) uses computational fluid dynamics to derive non-invasive FFR to determine the haemodynamic significance of coronary artery lesions. Studies have demonstrated good diagnostic accuracy of CT-FFR and reassuring short-term clinical outcome data.As a prerequisite, high-quality CT coronary angiography (CTCA) images are required with good heart rate control and pre-treatment with glyceryl trinitrate, which would otherwise render CTCA as unsuitable for CT-FFR. CT-FFR can determine the functional significance of CAD lesions, and there are supportive data for its use in clinical decision-making. However, the downstream impact on myocardial ischaemic burden or viability cannot be obtained.Several challenges remain with implementation of CT-FFR, including interpretation, training, availability, resource utilisation and funding. Further research is required to determine which cases should be considered for clinical CT-FFR analysis, with additional practical guidance on how to implement this emerging technique in clinical practice. Furthermore, long-term prognostic data are required before widespread clinical implementation of CT-FFR can be recommended.While there are several potential opportunities for CT-FFR, at present there remain important systemic and technical limitations and challenges that need to be overcome prior to routine integration of CT-FFR into clinical practice.

Rescue treatment and follow-up intervention of a left main acute myocardial infarction with typical carina shift under 3D optical coherence tomography: A case report

BACKGROUND

Coronary intervention for bifurcation lesions is still challenging for interventional cardiologists. Left main (LM) bifurcation lesions have a higher risk due to the vast blood supply in this area and treatment choice is difficult. Ostial compromise of the side branch decreases patient prognosis, and its management is still an issue despite the different strategies and devices available.

CASE SUMMARY

A 42-year-old male patient was admitted to hospital due to chest pain and syncope. Coronary angiography showed acute LM occlusion. Following thrombus aspiration, a LM bifurcation lesion remained. Coronary angiography was repeated one week later, and at the same time, 3D optical coherence tomography (OCT) was carried out to better show the geometry of the bifurcation, which confirmed that the stenosis in the ostial left circumflex artery was caused by a long carina. After assessment of the plaque characteristics and the minimum lumen area, the cross-over strategy, kissing balloon inflation and proximal optimization technique were chosen to treat the bifurcation lesion. A “moving” carina was found twice during the intervention. Good stent apposition and expansion were confirmed by OCT after proximal optimization technique. The three-month follow-up showed good recovery and normal cardiac function.

CONCLUSION

3D-OCT can facilitate decision-making for coronary interventions in patients with critical bifurcation lesions.

Percutaneous Coronary Intervention for Coronary Bifurcation Lesions: Latest Evidence

PURPOSE OF REVIEW

This paper provides a synopsis of the best evidence to guide bifurcation percutaneous coronary intervention (PCI), with a focus on recent studies. This is with the aim of guiding the interventional cardiologist in choosing the best, evidence-based technique, to treat commonly encountered coronary bifurcations.

RECENT FINDINGS

Current evidence supports the use of provisional stenting for most anatomically suitable bifurcation lesions. Newer techniques for side branch protection in provisional stenting have been developed. When a two-stent strategy is required, use of a double-kissing crush technique is favoured, particularly in left main bifurcations. For bifurcation PCI, as in all complex procedures, intravascular imaging plays a key adjunctive role in improving procedural success. PCI for coronary bifurcation lesions is an ever-growing field with significant advancements in techniques and technology.