Side branch predilatation during percutaneous coronary bifurcation intervention: Long-term mortality analysis

BACKGROUND

Side branch predilatation (SBPD) during coronary bifurcation interventions is a technique that is not recommended by the latest guidelines. However, the data about the clinical outcomes after SBPD are surprisingly few.

AIMS

The current study aimed to explore the association between SBPD and mortality in long-term follow-up.

METHODS

All patients with coronary bifurcation stenoses revascularized with percutaneous coronary intervention were included in a prospective registry. Patients with stable angina and a bifurcation lesion with ≥50% diameter stenosis were included in the current analysis. Patients were assigned to two groups - those with SBPD(+) and those without SBPD(-). Propensity score matching was performed to equalize the risk factors and severity of coronary artery disease between the groups. A Kaplan-Meier analysis with a log-rank test for between-group differences was also performed.

RESULTS

From January 2013 to June 2021, 813 patients were included in the final study population. The mean age was 67 (10) years. After propensity score matching, 648 patients remained for analysis - 324 in each group. At a median follow-up of 57 months patients in the SBPD(+) group had a higher all-cause mortality (n = 107 (33%) vs. n = 98 [30.2%]; P = 0.045) and cardiovascular mortality (n = 82 [25.3%] vs. n = 70 [21.6%]; P = 0.03) when compared with SBPD(-) patients. SBPD was independently associated with all-cause and cardiovascular mortality.

CONCLUSION

SBPD treatment of coronary bifurcation stenoses is associated with worse patient survival in the follow-up of up to 8 years. SBPD treatment gives better angiographic results, but this did not translate into better clinical outcomes.

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

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

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.

Influence of different postballoon expansion procedures: A finite element analysis

BACKGROUND

Postballoon expansion is considered as an appropriate procedure for adequate stent expansion for coronary bifurcation lesions. Two postballoon expansion procedures are currently recommended: proximal optimization technique (POT)/side/POT and POT/kiss/POT. However, the effects of the two postballoon expansion treatments are different. There is a lack of biomechanical study to quantify the difference.

PURPOSE

It is recognized that biomechanical factors influence the occurrence of Major Cardiovascular Adverse Events (MACE), which includes recurrent angina pectoris, acute myocardial infarction and coronary heart disease death. The current paper evaluated the two postexpansion strategies and quantified biomechanical parameters to provide a basis for clinical decisions.

METHODS

Based on the CT angiography (CTA) data of a patient diagnosed with coronary bifurcation lesions, a personalized coronary bifurcation lesion model was constructed, and the surgical procedure after two expansions was simulated. The POT/side/POT and POT/kiss/POT expansion procedures were analyzed from the perspective of biomechanics through finite element analysis. The biomechanics factors, including the percentage of stent malapposition and stent occlusion at the side branch (SB) opening, the stent ellipse index of proximal main vessel (PMV) segment, the minimum lumen area of the stent vessel segment and the stress distribution of the vessel wall, were used to quantify clinician concerns about factors affecting patient outcomes. The factors include stent adhesion, SB open stent occlusion, poor stent deformation, patency effect of vessel stenosis, and vessel wall damage.

RESULTS

Both postexpansion procedures were successfully simulated. The malapposition rate during POT/side/POT was larger (1.2% vs. 0.42%) and stent occlusion at the SB opening from the cross-section perpendicular to the SB opening after the POT/side/POT procedure was 0.20%, compared with 0.00% after POT/kiss/POT. POT/kiss/POT produced a larger PMV segment stent ellipse index. Minimum lumen area after POT/side/POT was 5.6 mm² and after POT/kiss/POT 5.9 mm² . POT/kiss/POT produces an effect of greater vascular stress than POT/side/POT.

CONCLUSION

Numerical simulations provide a quantitative analysis to inform clinicians of the differences between preoperative planning and surgical procedures. Biomechanical analysis of the differences between the two postexpansion strategies found that the POT/kiss/POT procedure resulted in better stent fit, less occlusion of the SB open stent and better vascular patency but also resulted in poor stent deformation and caused greater vessel wall stress. The current study informs rationales for clinical understanding of postexpansion strategies.

Reliability and Safety of a Side-Branch Jailed Second-Generation Optical-Pressure Guidewire in a Physiology-Guided Bifurcation-PCI In Vitro Model

BACKGROUND

The treatment of a coronary bifurcation with a single stent (the provisional stenting technique) is associated with a good outcome in most cases. In the majority of cases, after provisional stenting technique, a residual significant angiographic stenosis is associated with the absence of ischemia when fractional flow reserve (FFR) is measured. Jailing an optical pressure guidewire in the side branch (SB) could potentially reduce unnecessary SB interventions after provisional stenting technique. The aim of this study was to compare distal pressure to aortic pressure ratio (Pd/Pa) measurements between 2 second-generation optical pressure guidewires in bifurcation treatment-a jailed wire (JW) and a second free-floating wire (FW) advanced into the SB after stenting.

METHODS

In an in vitro bifurcation hydrodynamic model with pressure sensors, a JW was advanced into the SB and the FW into the main branch. Bifurcation stenting is performed with the proximal optimization technique (POT)-side-POT technique using a 3.0 x 22-mm stent, a 4.0 x 12-mm noncompliant balloon for the POT, and a 2.5 x 12-mm semicompliant balloon for the SB opening. The same steps were performed in a second model where a surgical clamp was placed in the main vessel to lower overall absolute values pressures.

RESULTS

A strong correlation was found between JW and FW values (Pearson's coefficient, r=0.91). All wires could be safely retrieved.

CONCLUSION

In bifurcation stenting, the Pd/Pa value of a second-generation optical pressure guidewire jailed in the SB is reliable compared with a FW inserted after stent implantation.

Effect of Drug-Coated Balloon in Side Branch Protection for de novo Coronary Bifurcation Lesions: A Systematic Review and Meta-Analysis

Background: At present, there are a variety of treatment strategies for percutaneous coronary intervention. The role of drug-coated balloon (DCB) in the treatment of side branch for de novo coronary bifurcated lesions (CBL) is unclear.

Objective: To examine the effect of DCB in side branch protection for de novo CBL.

Methods: Electronic databases, including Pubmed, Embase, the Web of science, Cochrance library, CNKI, CBM, WanFang Data and VIP were searched for studies that compared DCB with non-drug-coated balloon (NDCB) in side branch protection for de novo CBL from inception through July 7th, 2021. The primary outcome was target lesion revascularization (TLR). Secondary clinical outcomes included myocardial infarction (MI), cardiac death (CD). The angiographic outcomes included side branch late lumen loss (LLL), minimum lumen diameter (MLD), diameter stenosis (DS) and binary restenosis (BR). The target lesion failure (TLF) was also analyzed.

Results: A total of 10 studies, including 5 randomized controlled trials and 5 non-randomized observational studies, with 934 patients were included. Meta-analysis results of angiographic outcomes suggested that DCB group had the less LLL, DS and BR and the higher MLD compared with NDCB group at follow-up (P < 0.05). Meta-analysis results of clinical outcomes suggested that the significant difference in the TLR, MI and CD between DCB group and NDCB group has not been found yet (P > 0.05). However, the MACE of DCB group was significantly less than that of NDCB group at 9-month follow-up [OR = 0.21, 95%CI (0.05, 0.84), P = 0.03] and 12-month follow-up [OR = 0.45, 95%CI (0.22, 0.90), P = 0.02]. In addition, there was no significant difference in TLF between DCB group and NDCB group (P > 0.05).

Conclusions: DCB had great effect in side branch protection for de novo CBL at short and medium-term follow-up with no reduction in the procedural success rate.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=267426, PROSPERO [Identifier: CRD42021267426].

In Vivo Based Fluid-Structure Interaction Biomechanics of the Left Anterior Descending Coronary Artery

A fluid-structure interaction-based biomechanical model of the entire left anterior descending coronary artery is developed from in vivo imaging via the finite element method in this paper. Included in this investigation is ventricle contraction, three-dimensional motion, all angiographically visible side branches, hyper/viscoelastic artery layers, non-Newtonian and pulsatile blood flow, and the out-of-phase nature of blood velocity and pressure. The fluid-structure interaction model is based on in vivo angiography of an elite athlete's entire left anterior descending coronary artery where the influence of including all alternating side branches and the dynamical contraction of the ventricle is investigated for the first time. Results show the omission of side branches result in a 350% increase in peak wall shear stress and a 54% decrease in von Mises stress. Peak von Mises stress is underestimated by up to 80% when excluding ventricle contraction and further alterations in oscillatory shear indices are seen, which provide an indication of flow reversal and has been linked to atherosclerosis localization. Animations of key results are also provided within a video abstract. We anticipate that this model and results can be used as a basis for our understanding of the interaction between coronary and myocardium biomechanics. It is hoped that further investigations could include the passive and active components of the myocardium to further replicate in vivo mechanics and lead to an understanding of the influence of cardiac abnormalities, such as arrythmia, on coronary biomechanical responses.

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

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

Patency of Posterior Circulation Branches Covered by Flow Diverter Device: A Hemodynamic Study

Objective: Flow diverter devices are increasingly used in the treatment of posterior circulation aneurysms, sometimes necessarily involving ostia of side branches and perforators. The aim of this study was to identify the hemodynamic influence of flow diverters on side branches and perforators of the posterior circulation. Methods: We performed a retrospective study of consecutive patients treated by a flow diverter device for posterior circulation aneurysms with anterior inferior cerebellar artery (AICA) or posterior inferior cerebellar artery (PICA) involvement. Computational fluid dynamics (CFD) were used to discern hemodynamic changes of branches after deployment of the flow diverter. Results: We studied 18 branches from 17 patients (mean age, 50.72 ± 8.17 years). No branches were occluded on immediate angiography and later follow-up. Average flow velocity in aneurysms decreased from 0.077 ± 0.065 m/s to 0.025 ± 0.025 m/s (p < 0.01). Average flow velocity in branch ostia decreased from 0.29 ± 0.14 m/s to 0.27 ± 0.16 m/s (p = 0.189). The difference in flow velocity reduction ratio between aneurysms and branches was statistically significant (68.8 vs. 9.5%; p < 0.001). The mean pressure in branch ostia increased from 10,717.4 ± 489.0 to 10,859.0 ± 643.4 Pa (p < 0.01). Conclusion: While a flow diverter device is capable of slowing down aneurysmal inflow, it is unable to block the flow into branches and perforators when used in the treatment of posterior circulation aneurysms; flow velocity in branches even increased in some cases. With a low branch occlusion ratio, it may be acceptable to cover posterior circulation branches and perforators if unavoidable.

Small side branch compromise related to main vessel stenting: A retrospective cohort study comparing different treatment strategies

Treatment strategies for small side branch compromise related to main vessel stenting are not well investigated and not established.This study is to compare the clinical prognosis of different strategies for bifurcations with or without percutaneous coronary intervention (PCI) of small side branch after it compromised.A total of 119 consecutive bifurcation subjects from January 2013 to March 2015 were enrolled, all bifurcations were characterized by small side branch (1.5 mm ≤side branch diameter ≤2.5 mm). Subjects were assigned into side branch treatment (SBT) group and nonside branch treatment group (NSBT) according to whether advanced treatment of side branch was taken or not after it compromised. Major adverse cardiovascular event (MACE) was evaluated, so were the CCS angina and NYHA heart function classification.SBT subjects were associated with longer procedure time (46.7 vs 19.6 min, P < .001) and more complications (18.9% vs 0.0%, P < .001). 12 MACEs were followed including 4 in SBT group and 8 in NSBT group (10.8% vs 9.8%, P = 1.00). There were no significant difference between 2 groups regarding the CCS and NYHA classification, neither were the calculated classification improvement rate, respectively. In subgroup analysis for true and nontrue bifurcations, no statistical difference was found in terms of the MACE rate, the CCS, and NYHA classification improvement rate.Nontreatment of side branch will not increase the risk of MACE and will not worsen the CCS and NYHA classification when small side branch compromises during the bifurcation PCI.

A novel way to facilitate left ventricular lead implantation: Jailed catheter technique

An important therapeutic modality for heart failure with left ventricular dyssynchrony, left ventricular lead placement, cannot be achieved due to anatomic challenges in some cases. In the current case, a novel implantation technique to overcome an anatomic difficulty, angled takeoff of the side branch of the coronary sinus, was presented.

A "Jail Escape Technique" (JET) for distal side branch wiring during provisional stenting: Feasibility and first-in-man study

OBJECTIVE

To evaluate the feasibility of a novel technique for achieving distal SB access and improve strut apposition during provisional stenting.

BACKGROUND

While distal rewiring and stent expansion toward the side branch (SB) are associated with better results during provisional stenting of coronary artery bifurcation lesions, these techniques are technically challenging and often leave unopposed struts near the carina.

METHODS

The "Jail Escape Technique" (JET) is performed by passing the proximal tip of the SB wire between the main vessel (MV) stent struts and balloon before implantation, allowing the MV stent to push the SB wire against the distal part of the carina. The MV stent can then be deployed without jailing the SB wire. Distal SB access and strut distribution at the carina were tested in phantom and swine models. Stent distortion, dislodgement forces, and material damage were evaluated with tensile testing. Human feasibility was then tested on 32 patients.

RESULTS

Preclinical testing demonstrated that the SB wire was located at the most distal part of the carina and no strut malapposition at the carina was present after balloon inflation. Stent distortion, dislodgement forces, or material damage were not affected. JET was successfully performed in 30 of 32 patients. No major adverse cardiovascular events occurred in any patient at 6-month follow-up.

CONCLUSION

The "JET" enables distal SB access and eliminates strut malapposition at the carina. Further studies with larger numbers of patients are needed to further investigate this technique.

The Proximal Optimisation Technique for Intervention of Coronary Bifurcations

The proximal optimisation technique (POT) has been proposed as a strategy to improve the results of stent scaffolding of bifurcation lesions. It is a straightforward technique whereby a short, appropriately-sized balloon is inflated in the main vessel just proximal to the carina. The technique has several advantages: it reduces the risk of side branch compromise related to shifting of the carina, it improves stent apposition in the proximal main vessel, and it facilitates side branch access after main vessel stent implantation. When treating bifurcations, final kissing balloon dilation (KBD) has traditionally been used routinely to optimise angiographic results. However, recent clinical data have questioned this philosophy and bench models have demonstrated several shortcomings of KBD. Instead, the optimal strategy may centre on performing POT, followed by side branch dilation, and completed with a final (re)-POT. The following review article describes how to perform POT and presents the evidence to support its' routine use.

Comparative Case-Control analysis of a dedicated self-expanding Biolimus A9-eluting Bifurcation stent versus provisional or mandatory side branch intervention strategies in the treatment of coronary bifurcation lesions

BACKGROUND

In a number of coronary bifurcation lesions, both the main vessel and the side branch (SB) need stent coverage.

OBJECTIVES

To analyze the procedural performance and the impact on radiation times (RT) and contrast medium consumption (CMC) of the Axxess™ stent system (Biosensors, Switzerland) treating de novo bifurcation lesions (DBL).

METHODS

One hundred and ten consecutive prospectively enrolled cases (Axxess Group) and 110 age, sex, and lesion location matched controls undergoing mandatory (Group A, n = 56) or provisional (Group B, n = 54) SB intervention were analyzed.

RESULTS

Although more pre-dilatation was performed in the Axxess Group (92.7% vs. 46.4% [Group A] vs. 24.1% [Group B]), and more stents were used (2.4 vs. 1.2 vs. 1.05), RT and CMC were significantly lower in the Axxess Group [7.9 min/129 ml vs. 14.2 min/209 ml vs. 7.8 min/152 ml; P < 0.001]. Final Thrombolysis In Myocardial Infarction three flow in both branches was significantly more frequent in the Axxess Group (98.2% vs. 94.6% vs. 88.9%; P = 0.02), and post-interventional troponin T elevations were the lowest in the Axxess Group. Eighty one percent of the Axxess-stents could be implanted without technical difficulties. Difficult implantations procedures were mainly related to coronary anatomy. There was no safety concerns (cardiac death, stent-thrombosis) compared to controls. Cumulative 6-months MACE rates were 11% versus 23% versus 25%. TLR rates at 6-months were 5%, 18%, and 15%, respectively.

CONCLUSIONS

Axxess bifurcation stent system procedures were associated with significantly less RT and CMC compared to conventional DBL therapy strategies. Difficult coronary anatomy may hinder successful implantation and a learning curve has to be considered. © 2016 Wiley Periodicals, Inc.

Prediction of troponin elevation by means of intracoronary electrocardiogram during percutaneous coronary intervention of coronary bifurcation lesions (from COronary SIde Branch Residual IschemiA and COllateralization Assessment Study; COSIBRIA & Co Study

BACKGROUND

The influence of periprocedural ischaemia on coronary artery bifurcation stenting (percutaneous coronary intervention [PCI]) remains uncertain.

AIM

To determine the differences in rates of end procedural ischaemia after bifurcation lesion PCI detected with intracoronary electrocardiography (icECG).

METHODS

Unipolar icECGs were recorded before, during, and after stent placement and at the end of procedure in side branch (SB) and main branch (MB). Coronary wire was placed in all distal vessels with diameter > 1.5 mm to "map" the distal zones of ischaemia. The patient population consisted of patients with stable/unstable angina with troponin I evaluated before and after PCI.

RESULTS

We studied 147 patients (68% males) with mean age of 64 ± 9 years. One hundred and forty-two patients had icECG recordings at the end of PCI from all locations of the treated region; 36% of patients had MB ST segment elevation (STE) and 31% had icECG STE in the SB region (p = 0.378). The icECG had sensitivity of 82% and specificity of 81% to detect troponin I elevation, with positive predictive value of 81% and negative predictive value of 83%. The independent predictors of troponin increase (> 5 × N) were: sex (for female gender, OR = 0.130, CI 0.017-0.995, p = 0.049), previous myocardial infarction (OR = 33.23, CI 2.802-394.1, p = 0.005), and icECG STE in MB or SB or occlusion of secondary SB (OR = 7.877, CI 2.474-25.07, p < 0.001) and for any troponin elevation were double product - SBPxHR (OR = 0.999, CI 0.999-1.00, p = 0.022) and icECG STE in MB or SB or occlusion of secondary SB (OR = 9.762, CI 3.273-29.12, p < 0.001).

CONCLUSIONS

Intracoronary electrocardiography is a highly sensitive and specific method for determination of ischaemic regions and prediction of elevated troponin I.

Successful percutaneous coronary intervention for complex bifurcated lesions with combination of "Reverse wire technique" and "Reverse bent wiring with the crusade catheter" novel wire manipulation technique

We encountered a case of percutaneous coronary intervention for complex bifurcated lesions in the mid portion of the left anterior descending (LAD) artery. The diagonal artery branched from the LAD artery with a markedly angulated pattern and there was severe stenosis from just proximal to this diagonal artery. The "reverse wire technique facilitated with the Crusade catheter" enabled us to cross a guidewire through to the markedly angulated diagonal side branch (SB). Next, we adopted a mini-crushing stent strategy for this true bifurcated lesion. Thereafter, we adopted "reverse bent wiring with the Crusade catheter" for wire re-crossing to the incarcerated side branch, and successfully completed all procedures. This technique for successful wire re-crossing is simple but can be very effective in specific situations in practical percutaneous coronary intervention (PCI). Many PCI operators may empirically adopt this kind of wire manipulation technique. However, this case is the first report in the world describing the application of a "reverse bent wiring with the Crusade catheter" for wire re-crossing through a double-folded stent strut to a SB at the optimal point of the bifurcation. In this case, we made the most of the Crusade catheter. This catheter is a very useful device for multifactorial use in practical PCI. It can help us to perform complex PCI procedures successfully.

Clinical outcome after crush versus culotte stenting of coronary artery bifurcation lesions: the Nordic Stent Technique Study 36-month follow-up results

OBJECTIVES

The aim of the study was to compare long-term follow-up results of crush versus culotte stent techniques in coronary bifurcation lesions.

BACKGROUND

The randomized Nordic Stent Technique Study showed similar 6-month clinical and 8-month angiographic results with the crush and culotte stent techniques of de novo coronary artery bifurcation lesions using sirolimus-eluting stents. Here, we report the 36-month efficacy and safety of the Nordic Stent Technique Study.

METHODS

A total of 424 patients with a bifurcation lesion were randomized to stenting of both main vessel and side branch with the crush or the culotte technique and followed for 36 months. Major adverse cardiac events-the composite of cardiac death, myocardial infarction, stent thrombosis, or target vessel revascularization-were the primary endpoint.

RESULTS

Follow-up was complete for all patients. At 36 months, the rates of the primary endpoint were 20.6% versus 16.7% (p = 0.32), index lesion restenosis 11.5% versus 6.5% (p = 0.09), and definite stent thrombosis 1.4% versus 4.7% (p = 0.09) in the crush and the culotte groups, respectively.

CONCLUSIONS

At 36-month follow-up, the clinical outcomes were similar for patients with coronary bifurcation lesions treated with the culotte or the crush stent technique. (Nordic Bifurcation Study. How to Use Drug Eluting Stents [DES] in Bifurcation Lesions? NCT00376571).

Predictors and outcomes of side branch occlusion after main vessel stenting in coronary bifurcation lesions: results from the COBIS II Registry (COronary BIfurcation Stenting)

OBJECTIVES

This study sought to investigate the predictors and outcomes of side branch (SB) occlusion after main vessel (MV) stenting in coronary bifurcation lesions.

BACKGROUND

SB occlusion is a serious complication that occurs during percutaneous coronary intervention (PCI) for bifurcation lesions.

METHODS

Consecutive patients undergoing PCI using drug-eluting stents for bifurcation lesions with SB ≥2.3 mm were enrolled. We selected patients treated with the 1-stent technique or MV stenting first strategy. SB occlusion after MV stenting was defined as Thrombolysis in Myocardial Infarction flow grade <3.

RESULTS

SB occlusion occurred in 187 (8.4%) of 2,227 bifurcation lesions. In multivariate analysis, independent predictors of SB occlusion were pre-procedural percent diameter stenosis of the SB ≥50% (odds ratio [OR]: 2.34; 95% confidence interval [CI]: 1.59 to 3.43; p < 0.001) and the proximal MV ≥50% (OR: 2.34; 95% CI: 1.57 to 3.50; p < 0.001), SB lesion length (OR: 1.03; 95% CI: 1.003 to 1.06; p = 0.03), and acute coronary syndrome (OR: 1.53; 95% CI: 1.06 to 2.19; p = 0.02). Of 187 occluded SBs, flow was restored spontaneously in 26 (13.9%) and by SB intervention in 103 (55.1%) but not in 58 (31.0%). Jailed wire in the SB was associated with flow recovery (74.8% vs. 57.8%, p = 0.02). Cardiac death or myocardial infarction occurred more frequently in patients with SB occlusion than in those without SB occlusion (adjusted hazard ratio: 2.34; 95% CI: 1.15 to 4.77; p = 0.02).

CONCLUSIONS

Angiographic findings of SB, proximal MV stenosis, and clinical presentation are predictive of SB occlusion after MV stenting. Occlusion of sizable SB is associated with adverse clinical outcomes..

Impact of kissing balloon inflation on the main vessel stent volume, area, and symmetry after side-branch dilation in patients with coronary bifurcation lesions: a serial volumetric intravascular ultrasound study

OBJECTIVES

Intravascular ultrasound (IVUS) was performed to investigate the impact of kissing balloon inflation (KBI) on the main vessel (MV) stent volume, area, and symmetry after side-branch (SB) dilation in patients with coronary bifurcation lesions (CBL).

BACKGROUND

It remains controversial whether KBI would restore the MV stent area and symmetry loss after SB dilation.

METHODS

A total of 88 serial IVUS examinations of the MV were performed after MV angioplasty, MV stenting, SB dilation, and KBI in 22 patients with CBL. The MV stent was divided into proximal, bifurcation, and distal segments; the stent volume index (SVI), minimal stent area (MSA), stent symmetry index (SSI), and external elastic membrane (EEM) volume index were measured in 198 stent segments and compared after MV stenting, SB dilation, and KBI.

RESULTS

In the bifurcation segment, SVI, MSA, and SSI were significantly smaller after SB dilation than after MV stenting and KBI (SVI was 6.10 ± 1.50 mm(3)/mm vs. 6.68 ± 1.60 mm(3)/mm and 6.57 ± 1.60 mm(3)/mm, respectively, p < 0.05; MSA was 5.15 ± 1.30 mm(2) vs. 6.08 ± 1.40 mm(2) and 5.86 ± 1.50 mm(2), respectively, p < 0.05; and SSI was 0.78 ± 0.02 mm(2) vs. 0.87 ± 0.03 mm(2) and 0.84 ± 0.03 mm(2), respectively, p < 0.05). KBI restored the MV SVI, MSA, and SSI after SB dilation. In the proximal segment, SVI, MSA, and EEM volume index were significantly larger, but SSI was smaller after KBI than after MV stenting and SB dilation. In the distal segment, neither SB dilation nor KBI had a significant impact on the MV stent volume or symmetry.

CONCLUSIONS

This is the first comprehensive volumetric IVUS analysis of CBL, to our knowledge, demonstrating that KBI restores the MV stent volume, area, and symmetry loss after SB dilation in the bifurcation segment, and induces asymmetric stent expansion in the proximal segment.