Kissing Balloon Inflation in Percutaneous Coronary Interventions

Comparison of Stent Geometry Achieved by Different Side-Branch Ballooning Techniques For Bifurcation Provisional Stenting: The CRABBIS Trial

BACKGROUND

Stepwise provisional stenting is the most adopted approach for percutaneous coronary interventions (PCIs) in bifurcation lesions. During these procedures, the side branch (SB) may deserve treatment, but the best ballooning technique is still undetermined.

OBJECTIVES

The study sought to compare the stent configurations obtained by 2 SB ballooning sequences after main vessel (MV) stent implantation: the proximal optimization technique + kissing balloon inflation + final proximal optimization technique (PKP) vs the proximal optimization technique + isolated side branch dilation + final proximal optimization technique (PSP).

METHODS

We conducted a 1:1 prospective, randomized, single-center trial to compare bifurcation PCI performed with either PKP or PSP in left main or large (SB diameter >2.75 mm) coronary bifurcations (NCT05559424). The achieved stent configurations (in terms of expansion, apposition, and eccentricity at 5 different bifurcation segments) were evaluated using optical coherence tomography in the MV. The predefined primary study endpoint was minimum stent expansion at the distal MV segment.

RESULTS

A total of 60 patients undergoing bifurcation PCI according to stepwise provisional stenting were enrolled (30 randomized to PKP and 30 to PSP). At postintervention optical coherence tomography, minimum stent expansion at the distal MV segment was significantly higher with PKP as compared with PSP (99.3% ± 12.7% vs 83.8% ± 19.5%; P < 0.001). Additional relevant findings included a higher rate of malapposition in the bifurcation core and distal MV with PSP and improved SB scaffolding with PKP. No significant differences in terms of stent eccentricity were noted between PSP and PKP in all the segments analyzed.

CONCLUSIONS

The results of the present randomized trial show that during stepwise provisional stenting in left main or large bifurcations, the PKP ballooning sequence is associated with better stent configuration compared with the PSP.

Final kissing balloon dilatation in patients with coronary bifurcation lesions treated with an upfront provisional stenting strategy

BACKGROUND

The impact of final kissing balloon inflation (FKB) in patients treated with an upfront provisional strategy for coronary bifurcation lesions is controversial.

AIMS

We aimed to assess the impact of FKB on patient- and lesion-oriented outcomes in a large real-world cohort.

METHODS

The ULTRA-BIFURCAT registry was obtained by patient-level merging the BIFURCAT and ULTRA registries. Pairs of patients were generated with propensity score matching (PSM). The primary outcome of interest was major adverse cardiac events (MACE) - a composite of all-cause death, myocardial infarction (MI), target lesion revascularisation (TLR) or stent thrombosis. A lesion-oriented composite outcome (LOCO) - a composite of target vessel MI (TVMI) or TLR - along with each single component of MACE represented the secondary outcomes. Subgroup analyses included the site of bifurcation (unprotected left main [ULM] vs non-ULM), side branch involvement (true bifurcation vs non-true bifurcation), side branch diameter and lesion length. Follow-up was censored at 800 days.

RESULTS

A total of 5,607 patients undergoing a provisional stenting technique were selected for the present analysis. PSM generated 1,784 pairs. Between the matched patients with FKB versus no FKB, no significant difference in MACE was observed (9.0% vs 8.6%; p=0.68). FKB was associated with a lower rate of the LOCO (1.9% vs 2.9%; p=0.04) compared to the no FKB group, driven by lower rates of TVMI (0.2% vs 0.5%; p=0.03) and TLR (1.8% vs 2.6%; p=0.14). These results were confirmed in the subgroups of patients treated for bifurcations with side branches with a diameter >2.5 mm and for true coronary bifurcation lesions.

CONCLUSIONS

Among patients treated for coronary bifurcation lesions with provisional stenting, FKB had no significant impact on MACE but was associated with a mild reduction in the incidence of the LOCO.

Long-Term Outcomes of True Versus Nontrue Coronary Bifurcation Lesions Treated With Bioresorbable Polymer Sirolimus-Eluting Ultimaster Stent Under Intravascular Imaging Guidance

Limited evidence exists regarding the long-term outcomes of true versus nontrue coronary bifurcation lesions (CBLs) treated with current-generation drug-eluting stents and intravascular imaging guidance. The Sapporo Cardiovascular Clinic (SCVC) registry was a prospective, single-center, all-comers registry enrolling 1,727 consecutive patients treated with bioresorbable polymer sirolimus-eluting stent under complete imaging guidance. From this registry, 440 patients with CBLs (25.5%) were analyzed. Patients were categorized into the true and nontrue CBL groups according to the Medina classification (n = 234 and 206, respectively). The primary end point was the cumulative incidence of target vessel failure (TVF) (a composite of cardiac death, target vessel-related myocardial infarction, and clinically driven target vessel revascularization). The 1-stent strategy was predominantly chosen for the true and nontrue CBL groups (93.9% and 96.2%, respectively). During the median follow-up of 5.4 years, the cumulative incidence of TVF did not differ between true and nontrue CBL groups after adjustment for baseline differences (5-year incidence 22.0% vs 17.7%, adjusted hazard ratio 1.27, 95% confidence interval 0.79 to 2.05, p = 0.32). Although the Medina 0.0.1 lesions were very rare (1.1%), they had the highest rate of TVF among the Medina subtypes. Final kissing balloon inflation technique was associated with a lower incidence of TVF (p = 0.036). In conclusion, imaging-guided percutaneous coronary intervention with bioresorbable polymer sirolimus-eluting stent resulted in comparable long-term clinical outcomes between true and nontrue CBLs, primarily using the 1-stent technique.

Coronary bifurcation lesion treatment with the BioMime™ Branch sirolimus-eluting coronary side-branch stent system: A single-center experience

BACKGROUND

Coronary bifurcation lesions (CBL) comprise 15 %-20 % of percutaneous coronary procedures and remain a challenge despite advances in stent and interventional techniques. The BioMime™ Branch sirolimus-eluting coronary side-branch stent (BBSES) is specifically designed for CBL treatment in conjunction with a standard drug-eluting stent (DES). We report the first single-center experience of treating complex CBL with the novel BBSES.

METHODS

This is a retrospective, single-center study involving consecutive prospectively identified patients who underwent treatment of true CBL with the BBSES. The protocol included BBSES+DES implantation in the CBL and simultaneous final kissing balloon inflation.

RESULTS

Fifty-eight CBL were treated in 58 consecutive patients (89.6 % men, mean age 69.0 ± 9.5 years) presenting primarily with stable angina (84.4 %) and true (Medina 1,1,1,) CBL. Procedural success was 100 % without major adverse cardiac events (MACE). At a median follow-up of 18 months, one sudden death was reported that was accounted as possible late stent thrombosis. One patient had spontaneous myocardial infarction due to subacute thrombosis of a DES implanted in the main vessel proximally to the BBSES before the index procedure. Another patient was hospitalized for atrial fibrillation.

CONCLUSIONS

This is the first clinical experience to date of true CBL treatment with the BBSES demonstrating high procedural success, no in-hospital MACE and sustained clinical results at a median follow-up of 18 months.

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

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

Long-term clinical outcomes after kissing balloon inflation in patients with coronary bifurcation lesions treated with provisional stenting technique. Results from the real-world multicenter registry

OBJECTIVE

There is a lack of data regarding the long-term clinical efficacy of the kissing balloon inflation (KBI) after provisional stenting of coronary bifurcation lesions. The aim of this study was to analyze the impact of KBI on long-term clinical outcomes in patients undergoing provisional stenting for the coronary bifurcation lesions in a large real-world population.

METHODS

A total of 873 patients who underwent percutaneous coronary interventions (PCI) with provisional stenting and had clinical follow up were analyzed. Patients treated with 2-stent strategy were excluded. To reduce the effect of potential confounding factors in this observational study, propensity score matching was conducted.

RESULTS

KBI was performed in 325 patients (37.2%). The median follow-up duration was 37.3 months. Patients treated with KBI more often had a previous PCI (48.6% vs. 42.5% SMD = 0.123). Patients in non-kissing group had more complex coronary disease with higher prevalence of calcification (14.8% vs. 21.4% SMD = 0.172), thrombosis (2.8% vs. 5.8% SMD = 0.152) and longer side branch lesions (8.3% vs. 11.7% SMD = 0.113). There were no significant differences in the major adverse cardiac events including death, myocardial infarction, target lesion revascularization after KBI versus no KBI (15.4% vs. 15.7%, p = 0.28), in total cohort or in matched patients (17.1% vs. 15.8%, adjusted HR 1.01, 95% CI: 0.65-1.65, p = 0.95). The lack of effect of KBI on clinical outcomes was consistent across various subgroups including left main disease.

CONCLUSION

In this multicenter real-world registry, KBI did not improve long-term clinical outcomes in patients with coronary bifurcation lesions treated with provisional stenting technique.

Proximal Optimization Technique with an Ultra-Short Balloon as a Bailout Strategy for Stent Protrusion into the Left Main Trunk

A 64-year-old man presented with ST-elevation myocardial infarction. Emergent coronary angiography revealed severe stenosis at the proximal left anterior descending artery (LAD). A drug-eluting stent was deployed to land the stent's proximal edge on the LAD ostium. However, intravascular ultrasound (IVUS) after stent placement detected a slight stent protrusion from the LAD into the left main trunk (LMT), and the left circumflex artery (LCX) ostium was jailed by stent struts. We decided to perform the proximal optimization technique (POT) using an ultra-short balloon (4 mm in length) on the proximal site of the stent in the hope of dilating jailed struts at the LCX ostium and expanding malapposed struts at the LMT without proximal edge dissection. IVUS after POT confirmed a well-enlarged stent cell at the ostial LCX and adequate stent apposition at the LMT. Angiography showed preserved LCX circulation. At one-year follow-up, angiography showed no in-stent restenosis or LCX ostial stenosis. Optical coherence tomography showed remarkable expansion of the stent struts at the LCX ostium without any restenosis. A single POT with an ultra-short balloon could be a potential bailout strategy in the treatment of coronary bifurcation lesions with slight stent protrusion into the proximal main vessel.

Success rate and influencing factors of a balloon-push technique: A new technique to remove side branch-jailed struts under three-dimensional optical coherence tomography guidance

BACKGROUND

Kissing balloon inflation with distal guide wire recross can cause severe stent deformation depending on the stent link location with respect to the carina. The balloon-push technique, by which an inflated balloon is forced into the SB from the proximal main vessel (MV), is a feasible way to remove jailed struts without causing severe stent deformation.

AIMS

We investigated the procedural success rate, patterns of jailed strut removal at side branch (SB) orifices, factors related to failure of jailed strut removal, and follow-up angiogram results of the balloon-push technique.

METHODS

Between September 2015 and December 2020, 51 bifurcation stenting cases in which the balloon-push technique was used were enrolled. Based on three-dimensional optical coherence tomography images, strut removal with 1 stent crown length was defined as successful. Strut removal patterns were classified into two types: parallel-slide type (stent struts shifted distally into the MV lumen without inversion) and under-carina type (stent struts shifted distally under the carina with strut inversion or strut slide).

RESULTS

Procedural success was attained in 39 cases (success rate: 76.5%). Parallel-slide type and under-carina type occurred in 43% and 33% of cases, respectively. Factors related to failure were trifurcation lesions and a smaller pushed balloon-SB artery ratio compared with those in success cases (0.95 ± 0.18 vs. 1.10 ± 0.22, p = 0.032). Follow-up angiography was performed in 37 cases, and 2 cases had binary in-stent restenosis.

CONCLUSIONS

Removal of jailed struts with the balloon-push technique was feasible, without severe stent deformation, in bifurcation stentings.

Customizable Angioplasty Balloon-Forming Machine: Towards Precision Medicine in Coronary Bifurcation Lesion Interventions

The ability to customize the size and shape of angioplasty balloons may be useful in many clinical and research applications of coronary and endovascular intervention. Fully customizable balloons are outside the reach of most researchers due to their prohibitive cost. A small-scale balloon-forming machine was developed to produce fully customizable balloons. This study describes the creation of this customizable balloon-forming machine and identifies the key components of manufacturing a patient-specific balloon. Using a standard balloon-shaped mold created with a novel application of 3D stereolithography-printed resin, 104 PET balloon formation tests were conducted. A statistical study was conducted in which molding temperature and inflation air pressure were independent variables ranging from 100 to 130 °C and from 3.7 to 6.8 atm, respectively. The criteria for balloon-forming success were defined; pressure and temperature combined were found to have a significant impact on the success (p = 0.011), with 120 °C and 4.76 atm resulting in the highest chance for success based on a regression model.

Stenting techniques for coronary bifurcation disease: a systematic review and network meta-analysis demonstrates superiority of double-kissing crush in complex lesions

Objective

This study was aimed to compare different stenting techniques for coronary bifurcation disease (CBD).

Background

Percutaneous coronary intervention (PCI) remains controversial for CBD; over the years, several stent techniques for bifurcation lesions have been used. Current guidelines recommend a provisional single-stent strategy as the preferred method for coronary artery bifurcation lesions. However, several randomized controlled trials (RCT) indicated that two-stent techniques showed better clinical outcomes.

Methods

We systematically searched Embase, PubMed, and Web of Science to include RCTs. The primary endpoint was the major adverse cardiovascular event (MACE). Secondary outcomes were cardiac death, myocardial infarction (MI), target-lesion or target-vessel revascularization (TLR or TVR), and definite or probable stent thrombosis (ST). Finally, we used 26 RCTs and a total of 7257 individuals were randomly assigned to one of the 6 stent techniques and included in this network meta-analysis.

Results

In our network meta-analysis, double-kissing (DK) crush was significantly more superior to other 5 stent techniques in MACEs: OR vs. provisional 0.40 (95% CI 0.28–0.55); vs. culotte 0.40 (95% CI 0.26–0.60). DK crush ranked the most effective treatment for MACE (100%), MI (75%), ST (83%), and TLR (100%) in the rank probabilities analysis. In patients with complex bifurcation lesion defined by DEFINITION criteria, DK crush was notably more efficacious than provisional, culotte, and T-stenting/T-stenting and protrusion (TAP) in MACEs (OR vs. provisional 0.26, 95% CI 0.13–0.52) and TLR (OR vs. provisional 0.24, 95% CI 0.10–0.58).

Conclusion

Compared with other stenting techniques, DK crush had a lower incidence of MACEs in CBD. DK crush was significantly associated with a lower rate of MACEs in patients with complex bifurcation lesions defined by the DEFINITION criterion.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01979-9.

Clinical outcomes of the proximal optimisation technique (POT) in bifurcation stenting

BACKGROUND

Optimal deployment of coronary stents in a bifurcation lesion remains a matter of debate.

AIMS

We sought to capture the daily practice of bifurcation stenting by means of a worldwide registry and to investigate how post-implantation deployment techniques influence clinical outcomes.

METHODS

Data from the e-ULTIMASTER registry were used to perform an analysis of 4,395 patients undergoing percutaneous coronary intervention for bifurcation lesions. Inverse probability of treatment weights (IPTW) propensity score methodology was used to adjust for any baseline differences. The primary outcome of interest was target lesion failure (TLF) at one year (follow-up rate 96.2%).

RESULTS

The global one-year TLF rate was low (5.1%). The proximal optimisation technique (POT) was used in 33.9% of cases and was associated with a reduction in the adjusted TLF rate (4.0% [95% confidence interval: 3.0-5.1%] vs 6.0% [5.1-6.9%], p<0.01) due to a reduction of all components of this composite endpoint, except for cardiac death. Stent thrombosis was also positively impacted (0.4% [0.04-0.7%] vs 1.3% [0.8-1.7%], p<0.01). POT benefit was uniform across subgroups. Conversely, the use of the kissing balloon technique (36.5%) did not influence the adjusted TLF rate.

CONCLUSIONS

Despite a low one-year failure rate in this large bifurcation stenting cohort, POT was associated with a further reduction in the event rate and a uniform benefit across subgroups, suggesting systematic use of this deployment technique regardless of the bifurcation anatomy and stenting technique.

Differential Factors for Predicting Outcomes in Left Main versus Non-Left Main Coronary Bifurcation Stenting

Background: No large-scale study has compared the clinical and angiographic predictors of cardiovascular events in patients with left main bifurcation (LMB) and non-LMB stenting after second-generation DES implantation. Herein, we investigated differential clinical and angiographic factors for predicting outcomes in LMB versus non-LMB stenting. Methods: A total of 2648 patients with bifurcation lesions treated with second-generation DESs from the retrospective patient cohort were divided into an LMB group (n = 935) and a non-LMB group (n = 1713). The primary outcome was the 7-year incidence of target lesion failure (TLF), defined as the composite of cardiac death, myocardial infarction, and target lesion revascularization. Results: The incidence of TLF was 9.8%. Those in the LMB group were associated with a higher risk of TLF (14.2% versus 7.5%, p < 0.001) than those in the non-LMB group. Regarding the LMB group, independent predictors of TLF were chronic kidney disease (CKD), reduced left ventricular ejection fraction (LVEF), and two-stenting. Regarding the non-LMB group, CKD, reduced LVEF, old age, diabetes, and small diameter of the main vessel stent were independent predictors of TLF. Conclusions: The two-stent strategy could potentially increase TLF for the LMB lesions, and achieving the maximal diameter of the main vessel stent could result in better clinical outcomes for non-LMB lesions.

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

Background:

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

Methods:

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

Results:

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

Conclusions:

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

Registration:

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

An Upfront Two-Stent Strategy for True Coronary Bifurcation Lesions with A Large Side Branch in Acute Coronary Syndrome: A Two-Year Follow-Up Study

Background and Objectives: Little is known about the upfront two-stent strategy (U2SS) for true coronary bifurcation lesions (CBLs) in acute coronary syndrome (ACS). We aimed to present our two-year follow-up results on the U2SS by using different two-stent techniques for the true CBL with a large side branch (SB) in ACS patients, including unstable angina (UA), non-ST-segment elevation myocardial infarction (NSTEMI), and ST-segment elevation myocardial infarction (STEMI), and to identify independent predictors of the presence of major adverse cardiac events (MACEs) after intervention. Materials and Methods: The study included 201 consecutive ACS patients with true CBLs who underwent percutaneous coronary intervention (PCI) using U2SS from October 2015 to March 2018. Clinical outcomes at follow-up were assessed. MACE was defined as a composite of cardiac death, non-fatal myocardial infarction, and target lesion revascularization (TLR). Results: 31.3% of the patients had an UA, 46.3% had an NSTEMI, and 22.4% had an STEMI. CBL was most frequently located in the left anterior descending (LAD)/diagonal artery (59.2%). In total, 71.1% of the patients had a Medina classification (1,1,1). Overall, 62.2% of cases were treated with mini-crush stenting. Clopidogrel was given in 23.9% of the patients; 71.1% of the patients received everolimus eluting stent (EES); and 11.9% received a sirolimus eluting stent (SES). Final kissing balloon inflation was carried out in all patients, with an unsatisfactory rate of 5%. A proximal optimization technique sequence was successfully carried out in all patients. The MACE incidence was 16.9% with a median follow-up period of 2.1 years. There were seven cardiac deaths (3.5%). The TLR rate was 13.4% (n = 27), with PCI treatment in 16 patients, and coronary artery bypass grafting treatment in 11 patients. After multivariate penalized logistic regression analysis (Firth logistic regression), clopidogrel use (odds ratio (OR): 2.19; 95% confidence interval (CI): 0.41–2.51; p = 0.007) and SES use (OR: 1.86; 95% CI: 0.31–2.64; p = 0.014) were independent predictors of the presence of MACE. Conclusion: U2SS is feasible and safe for the true CBLs with large and diseased SB in ACS patients, and is related to a relatively low incidence of MACE. Clopidogrel use and SES use may predict the MACE development in ACS patients treated using U2SS.

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

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

Kissing Balloon Technique for Infrapopliteal Angioplasty in Patients with Critical Limb Ischemia

BACKGROUND

This study aimed to analyze the technical aspects and follow-up findings regarding patients with critical limb ischemia who underwent the kissing balloon technique (KBT).

METHODS

Thirty patients (34 bifurcations) were enrolled in this retrospective analysis between September 2010 and February 2017. All patients were submitted to infrapopliteal intervention for critical limb ischemia. The KBT is the primary treatment in 3 situations: for cases with >70% stenosis of the main artery located less than 1 cm of the bifurcation, occlusion of one branch with greater than 50% stenosis of the contralateral branch, or greater than 50% bilateral stenosis. Stents were considered in cases of recoil greater than 30% or flow-limiting recoil and were used in 7 of the 34 bifurcations (20.5%).

RESULTS

Primary patency at 30 days, 1 year, and 2 years was 100%, 68.1%, and 68.1, respectively. Limb salvage rates at 30 days, 1 year, and 2 years were 100%, 86.6%, and 65.0%, respectively. Wound healing rates at 30 days, 6 months, 1 year, and 2 years were 7.1%, 34.4%, 44.5%, and 68.7%, respectively. The bifurcations of the V-shape and T-shape groups were compared in terms of wound healing, primary patency, and limb salvage. No differences were observed in wound healing (P = 0.268), primary patency (P = 0.394), and limb salvage (P = 0.755).

CONCLUSIONS

The KBT is a feasible bifurcation approach for infrapopliteal angioplasties to maintain the patency of both branches after ballooning. The comparison between the anterior tibial artery and tibioperoneal trunk bifurcation and the peroneal artery and posterior tibial artery bifurcation revealed no difference in wound healing, primary patency, and limb salvage.

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

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

Double kissing mini-culotte versus mini-culotte stenting: insights from micro-computed tomographic imaging of bench testing

AIMS

This study aimed to evaluate the morphologic characteristics of double kissing (DK) mini-culotte and mini-culotte stenting through imaging of bench testing.

METHODS AND RESULTS

DK mini-culotte and mini-culotte stenting were performed in two silicone bifurcated phantoms with branch vessel diameter differences of 0.5 mm (Model 1) and 1.25 mm (Model 2), and their morphologic characteristics were evaluated by micro-computed tomography. In Model 1, metal carina length (0.25±0.13 mm vs 0.55±0.15 mm), area stenosis of the side branch ostium (SBO) (4.65±3.24% vs 12.5±3.93%), and maximum distance of malapposed struts for the wall facing the SBO (0.27±0.08 mm vs 0.49±0.15 mm) were lower in the DK mini-culotte group than in the mini-culotte group. In Model 2, metal carina length (0.21±0.47 mm vs 0.47±0.12 mm), SBO area stenosis (5.13±3.37% vs 15.00±6.18%), and maximum distance of malapposed struts (0.32±0.13 mm vs 0.68±0.10 mm) were also lower in the DK mini-culotte group. The results of factorial analysis showed that maximum distance of malapposed struts tended to be shorter in Model 1 (F=4.226, p=0.062).

CONCLUSIONS

Compared with mini-culotte stenting, DK mini-culotte stenting was associated with shorter metal carina length, shorter maximum distance of malapposed struts, and smaller SBO area stenosis. Thus, DK mini-culotte stenting may obtain better morphologic characteristics.

Impact of Final Kissing Balloon and of Imaging on Patients Treated on Unprotected Left Main Coronary Artery With Thin-Strut Stents (From the RAIN-CARDIOGROUP VII Study)

Few data are available about the impact on outcomes of procedural strategies for percutaneous coronary intervention with thin-struts stents on unprotected left main (ULM): 792 patients with an ULM stenosis treated with percutaneous coronary intervention with thin-strut stents were enrolled in the present multicenter registry. Target lesion revascularization (TLR) was the primary end point. MACE (a composite of all-cause death, myocardial infarction, TLR, and stent thrombosis) and its single components, along with target vessel revascularization were the secondary end points. Subgroup analyses were performed according to complex versus noncomplex bifurcation lesions. After 16 months, 5.5% of patients experienced a TLR. At multivariate analysis, provisional stenting (odds ratio [OR] 0.46: 0.85 to 0.23, p = 0.006), use of imaging (OR 0.45: 0.23 to 0.98, p = 0.003) and final kissing balloon (FKB) (OR 0.41: 0.83 to 0.21, p = 0.001) reduced risk of TLR. FKB reduced risk of overall TLR only for 2 stents-strategy (6.2% vs 32.4%, p <0.05), but not for provisional strategy (3.8% vs 3.7%, p = 0.67). Intracoronary imaging reduced risk of overall TLR both for provisional (2.2% vs 5.4%) and for 2-stents strategy (7.3% vs 14.1% p <0.05 for both, all confidence interval 95%). In conclusion, TLR for ULM patients treated with thin-strut stents is infrequent. Provisional stenting was noninferior compared with 2-stents apart from complex lesions. Benefit from intracoronary imaging is consistent for different strategies, whereas that from FKB persists only for 2-stents.

Crush versus Culotte stenting techniques for coronary bifurcation lesions: A systematic review and meta-analysis of clinical trials with long-term follow-up

BACKGROUND

In patients with complex true coronary bifurcation lesions (CBLs), Crush or Culotte stenting has been the commonest approaches of percutaneous coronary intervention (PCI). However, the optimal one remains in debate.

METHODS

A systematic review and meta-analysis of cohort studies searched from PubMed, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Chinese National Knowledge Infrastructure (CNKI), VIP information database, and WangFang Data Information Site, to compare the long-term safety and efficacy of PCI with Crush versus Culotte in patients with CBLs. The primary end point was target lesion revascularization (TLR) and secondary end points were a composite of major adverse cardiac events (MACE) including cardiac death (CD), myocardial infarction (MI), stent thrombosis (ST), and target vessel revascularization (TVR) by PCI or bypass surgery, and each individual component at long-term follow-up. Furthermore, omitting each study in turn was used to sensitivity analysis for high heterogeneity of studies.

RESULTS

A total of 7 studies were included to perform a meta-analysis, 3 randomized trials and 4 observational studies with 2211 patients, 1281 treated with Crush and 930 with Culotte. There was no significant difference in TLR and MACE between Crush and Culotte [RR 0.76, 95% CI (0.48-1.23), I = 57%; RR 0.78, 95% CI (0.47-1.29), I = 83%, respectively]. ST tended to be lower in patients treated with Crush [RR 0.61, 95% CI (0.37-1.01), I = 23%]. CD and MI were comparable between the 2 groups [RR 0.80, 95% CI (0.43-1.49), I = 0%; RR 0.74, 95% CI (0.49-1.13), I = 32%, respectively]. TVR was also associated with the similar risk [RR 0.76, 95% CI (0.49-1.16), I = 60%]. However, high heterogeneity was detected for TLR, MACE, and TVR, and the source of heterogeneity was DKCRUSH-III study by Chen, SL.

CONCLUSIONS

In the treatment of coronary bifurcation lesions, TLR and MACE were not significant difference between the Crush and Culotte groups, but TLR and MACE were also regarded as high heterogeneity mainly due to better outcomes achieved by DK Crush and there was a trend toward lower ST in the Crush group. Crush, particularly DK Crush, may be superior to conventional Culotte for treatment of CBLs.

PROSPERO REGISTRATION NUMBER

CRD42018111868.

Efficacy of the proximal optimization technique on crossover stenting in coronary bifurcation lesions in the 3D-OCT bifurcation registry

AIM

We sought to investigate the efficacy of the proximal optimization technique (POT) on crossover stenting followed by side branch (SB) dilation under optical coherence tomography guidance in a multicenter registry study.

METHODS AND RESULTS

A total of 135 bifurcation lesions in 134 patients were divided into POT (n = 52) and non-POT groups (n = 83). The POT was performed before SB dilatation (pre-POT; n = 26), finally (final-POT; n = 12), at both timing (re-POT; n = 13), and uncertain (n = 1). There were no significant intergroup differences in the success rate of guide wire re-crossing (GWR) into the optimal cell (72% vs. 65%), incidence of the link-free type in the configuration of the SB jailed struts (51% vs. 49%), or incomplete strut apposition at the bifurcation (13 ± 11% vs. 10 ± 9%). However, insufficient stent expansion close to the carina in the proximal main vessel (MV) due to inappropriate POT was likely to induce greater incomplete strut apposition (ISA) around the bifurcation. Only re-POT provided more symmetric proximal MV expansion, while pre- and final-POT did not.

CONCLUSION

The POT did not provide the expected beneficial effects, such as reduction of ISA or more optimal GWR, under the OCT guidance. Wide stent expansion in the proximal MV induced by the POT increased the likelihood of achieving optimal GWR, whereas symmetric stent expansion was provided by re-POT.

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

OBJECTIVES

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Kissing Balloon Technique for Angioplasty of Tibioperoneal Arteries Bifurcation Using Pedal Arterial Retrograde Revascularization

Background

Kissing Balloon Technique using retrograde pedal approach together with anterograde common femoral artery (CFA) approach could be the treatment of choice in patients with diseased infrapopliteal artery bifurcation. We report seven cases where the KBT was utilized for the treatment of diseased infrapopliteal artery bifurcation using retrograde pedal access in conjunction with the conventional common femoral artery (CFA) access.

Methods

We reviewed all seven cases that underwent KBT with the combination of pedal and common femoral access in a single-center study from 2014 to 2015 utilizing Rutherford classification severity index; all cases were deemed stage 3 (severe claudication) to stage 6 (severe ischemic ulcers or frank gangrene). With the exception of two cases, contralateral femoral access was obtained, with sheath sizes varying from 4 to 6 French for both CFA and pedal access. Ultrasound was utilized for ipsilateral pedal access in all seven cases.

Results

Arterial revascularization was successfully achieved by the KBT in all patients without any complications. All patients achieved procedural success, which is defined as residual stenosis of less than 30% with no dissection or thrombosis and clinical success that is defined as resolution of symptoms (absence of intermittent claudication and healing of the ulcer) as well as improvement in the arterial brachial index (ABI). During follow-up, out of the seven cases, repeat angiogram was performed for one case, which showed patent arteries with no residual lesions.

Conclusions

In patients with popliteal and tibioperoneal trunk bifurcation lesions, Kissing Balloon Technique using retrograde pedal access in conjunction with the conventional anterograde access appeared to be successful, safe, and effective technique with lower access site complications and shorter procedure time.

Should kissing balloon inflation after main vessel stenting be routine in the one-stent approach? A systematic review and meta-analysis of randomized trials

The KBI (kissing balloon inflation) technique is considered the default strategy for the two-stent approach in real world practice. Studies comparing KBI and No-KBI in patients undergoing the one-stent approach have reported conflicting results. The meta-analysis was performed to compare the clinical outcomes of the KBI strategy and the No-KBI strategy for coronary bifurcation lesions in the one-stent approach. Five randomized studies were included, and a total of 1264 patients were involved in the meta-analysis. The primary outcome was cardiac death. The secondary end points were stent thrombosis, MI (myocardial infarction), target lesion revascularization (TLR), target vessel revascularization (TVR), and main vessel and side branch restenosis. Compared with the No-KBI strategy, the KBI strategy was associated with a significant reduction in side branch restenosis (OR: 0.44, 95% CI: 0.30–0.64, p<0.001). A high risk of main vessel restenosis was found in the KBI group (OR: 2.96, 95% CI: 1.74–5.01, p<0.001). There were no significant differences in rates of cardiac death (OR: 1.89, 95% CI: 0.60–5.95, p = 0.28), stent thrombosis (OR: 0.98, 95% CI: 0.19–4.94, p = 0.98), MI (OR: 0.68, 95% CI: 0.33–1.44, p = 0.30), TLR (OR 1.14, 95% CI 0.68–1.90, p = 0.62), or TVR (OR 1.27, 95% CI 0.75–2.16, p = 0.38). Compared with the No-KBI strategy, the KBI strategy reduced the incidence of side branch restenosis and increased the risk of main branch restenosis in the one-stent approach. However, the clinical outcomes were similar between the KBI and No-KBI groups.

Prognostic impact of final kissing balloon technique after crossover stenting for the left main coronary artery: from the AOI-LMCA registry

It is still uncertain whether the final kissing balloon technique (FKBT) is mandatory after crossover stenting for the left main coronary artery (LMCA). Assessing Optimal Percutaneous Coronary Intervention for LMCA (AOI-LMCA) registry, a 6-center retrospective registry, enrolled 1809 consecutive patients for LMCA stenting in Japan. In the present analysis, 5-year clinical outcomes were compared between non-FKBT (n = 160) and FKBT (n = 578) groups in patients treated with crossover stenting with drug-eluting stents from the LMCA to the left anterior descending artery. Propensity score-matched analysis was also performed in 160 patient pairs. In the entire study population as well as in the propensity-matched population, the cumulative 5-year incidence of the primary outcome measure (target lesion revascularization: TLR) was not significantly different between the FKBT and non-FKBT groups (10.7 versus 14.3%, P = 0.49, and 11.8 versus 14.3%, P = 0.53, respectively). In the sensitivity analysis by the multivariable Cox proportional hazard model, the effect of FKBT relative to non-FKBT for TLR remained insignificant (adjusted HR 0.89, 95% CI 0.47–1.69, P = 0.72). Regarding the TLR location, there were no significant differences in the cumulative incidences of TLR for LMCA-only, for the main branch, and for the side branch between the 2 groups (2.2 versus 1.3%, P = 0.93, 11.8 versus 9.1%, P = 0.71, and 8.2 versus 7.6%, P = 0.82, respectively). FKBT after a 1-stent strategy for LMCA crossover stenting did not affect TLR and other clinical outcomes during 5-year follow-up.

Clinical Trial Registration: Assessing Optimal Percutaneous Coronary Intervention for Left Main Coronary Artery Stenting Registry (AOI LMCA Stenting Registry). http://www.umin.ac.jp/ctr/index/htm/. Unique Identifier: UMIN000014706.

Impact of stent deformity induced by the kissing balloon technique for bifurcating lesions on in-stent restenosis after coronary intervention

OBJECTIVES

To investigate the impact of stent deformity induced by final kissing balloon technique (KBT) for coronary bifurcation lesions on in-stent restenosis (ISR).

BACKGROUND

In experimental models, the detrimental effects of KBT have been clearly demonstrated, but few data exists regarding the impact of proximal stent deformity induced by KBT on clinical outcomes.

METHODS

We examined 370 coronary lesions where intravascular ultrasound (IVUS)-guided second-generation drug-eluting stent (DES) implantation for coronary bifurcation lesions was performed. Based on IVUS analysis, the stent symmetry index (minimum/maximum stent diameter) and stent overstretch index (the mean of stent diameter/the mean of reference diameter) were calculated in the proximal main vessel.

RESULTS

The stent symmetry index was significantly lower (0.75 ± 0.07 vs 0.88 ± 0.06, P < 0.0001) and the stent overstretch index was significantly higher (1.04 ± 0.08 vs 1.01 ± 0.06, P = 0.0007) in lesions with KBT (n = 174) compared to those without KBT (n = 196). The number of two-stent technique in lesions with KBT was 31 (18%). In multivariate analysis, the degree of stent deformity indices was not associated with ISR in lesions with KBT; however, two-stent technique use was the only independent predictor of ISR at 8 months (hazard ratio: 3.96, 95% confidence interval: 1.25-12.5, P = 0.01).

CONCLUSIONS

Second-generation DES deformity induced by KBT was not associated with mid-term ISR.

Impact of guidewire recrossing point into stent jailed side branch for optimal kissing balloon dilatation: core lab 3D optical coherence tomography analysis

AIMS

We aimed to investigate the influence of the guidewire recrossing point on the incidence of incomplete stent apposition (ISA) after kissing balloon dilatation (KBD), and also clinical and angiographic outcome at nine months in a prospective multicentre registry.

METHODS AND RESULTS

One hundred and five patients underwent single crossover stenting across the side branch (SB) and subsequent KBD. The jailing configuration of the SB orifice and the guidewire recrossing position were assessed by off-line 3D-OCT in the core lab. We defined the cases that achieved both link-free carina configuration and distal recrossing as the LFD group (54 cases), and the other cases as the non-LFD group (51 cases). ISA in the LFD group was significantly smaller than that in the non-LFD group (6.7±5.9% vs. 17.0±10.5%, p<0.0001). The distal recrossing rate was 83%. Proximal recrossing increased ISA compared with distal recrossing, particularly in parallel bifurcations (17.1±10.1% vs. 6.3±6.0%, p<0.0001). At follow-up, though event rates did not differ, SB restenosis in the non-LFD group tended to be higher than in the LFD group (20.5% vs. 8.3%, p=0.1254).

CONCLUSIONS

The guidewire recrossing point and the location of a stent link at the SB orifice had an influence on the ISA. KBD with optimal conditions under 3D-OCT guidance may reduce SB restenosis.

Treatment of coronary bifurcation lesions: current knowledge and future perspectives

Coronary lesions at bifurcation sites are frequent and still remain a challenging subset for the interventional cardiologist. Although in the last years the provisional stenting technique has shown more consistent results, coronary bifurcation interventions still share a worse procedural success rate and increased rates of mid- and long-term cardiac events. Most of the dedicated devices proposed in the last few years have failed to show improved results when compared with standard devices. The broader use of imaging techniques, such as intravascular ultrasound and optical coherence tomography, lead to a better understanding of the real anatomy of bifurcations and has shown to be a great tool for percutaneous coronary intervention optimization. Preliminary results come from drug-coated balloons and bioresorbable vascular scaffolds, especially for the 'leave nothing behind' concept, particularly interesting in this setting of lesions.

Feasibility and usefulness of three-dimensional optical coherence tomography guidance for optimal side branch treatment in coronary bifurcation stenting

BACKGROUND

For the treatment of coronary bifurcation lesions, optimal guidewire (GW) recrossing after main vessel stenting is important for good stent apposition at the side branch (SB) orifice in kissing balloon inflation (KBI).

METHODS

We analyzed 150 bifurcation lesions treated with single stenting following KBI in the three-dimensional optical coherence tomography (3D-OCT) bifurcation registry study (2015-16) and a single center experience (2012-16). OCT examination was performed after GW recrossing to the SB and after KBI. Patients were divided into two-dimensional (2D, n=78) and 3D groups (n=72) according to 2D- or 3D-OCT guidance. GW recrossing position, jailing configuration of the stent over the SB (divided into Link-connecting type: stent link connecting to the carina and Link-free type: no stent link at the carina) and stent apposition were compared between the groups.

RESULTS

Distal GW recrossing was achieved in 75.6% and 91.7% in the 2D and 3D groups, respectively (P=0.004). Compared with the 2D group, the incidence of incomplete stent apposition (ISA) toward the SB in the 3D group tended to be lower in the whole cohort (14.5±13.6% vs 10.0±9.0%, P=0.077), and was significantly lower in left main trunk bifurcations (18.7±12.8% vs 10.3±8.9%, P=0.014). Independent contributors to ISA were the Link-connecting type (β 0.089, P<0.001), distal GW recrossing (β -0.078, P=0.001), and age (β -0.0020, P=0.012).

CONCLUSION

Optimal GW recrossing under 3D-OCT guidance is feasible and improves stent apposition, which may lead to a better clinical outcome in the treatment of bifurcation lesions.

Contemporary Approach to Coronary Bifurcation Lesion Treatment

Coronary bifurcations are frequent and account for approximately 20% of all percutaneous coronary interventions. Nonetheless, they remain one of the most challenging lesion subsets in interventional cardiology in terms of a lower procedural success rate and increased rates of long-term adverse cardiac events. Provisional side branch stenting should be the default approach in the majority of cases and we propose easily applicable and reproducible stepwise techniques associated with low risk of failure and complications.

CFD analysis of strut influence on blood flow in stent-implanted left main coronary artery bifurcation

We numerically studied blood flows in a simulated branching pipe of coronary artery bifurcation, which is affected by stent implantation. We found that stent struts provide effects as guide vanes and blockages on the flow into circumflex branch. The former effect increases the flow rate and shear stress on the arteriosclerosis-prone site. The blockage effect may overwhelm the guide effect depending on a strut position against the inflow.

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.

Difference in vascular response between sirolimus-eluting- and everolimus-eluting stents in ostial left circumflex artery after unprotected left main as observed by optical coherence tomography

BACKGROUND

Kissing-balloon technique (KBT) is commonly performed during percutaneous coronary intervention of distal unprotected left main coronary artery (ULM) aiming at obtaining optimal opening of the side branch (left circumflex artery; LCX) ostium. Nonetheless, detailed evaluation of vascular response to stents in LCX ostium is lacking. We therefore evaluated the vascular response to different drug-eluting stents (DES) in ostial LCX after ULM by means of optical coherence tomography (OCT).

METHODS

We prospectively enrolled 38 consecutive patients with ULM disease, who were treated with single-stent procedure using DES, crossover the ULM-left anterior descending artery (LAD) followed by KBT. Twelve patients were treated with sirolimus-eluting stents (SES) and 26 patients were treated with everolimus-eluting stents (EES). OCT was conducted at post-PCI and 9-month follow-up. We evaluated the DES-vessel interactions and number of stent struts at the side branch (LCX) ostium (SO) at post-PCI, and compared the narrowing of ostial area at LCX between SES and EES.

RESULTS

Post-procedure, the number of stent struts at SO was significantly higher in SES compared to EES (median 14.47% vs 0.19%, p<0.001). The narrowing of LCX ostial area at follow-up was more pronounced in SES compared with EES (29.16% vs 2.46%, respectively, p<0.001). Linear regression analysis showed a high correlation between the number of stent struts in LCX ostium and ostial area narrowing (r=0.771, p<0.001).

CONCLUSIONS

OCT showed differences between EES- and SES-vessel interactions at ULM bifurcation PCI. Number of LCX ostium struts at post-PCI impacted the narrowing of ostial area at 9-month follow-up.

Efficacy of kissing balloon inflation after provisional stenting in bifurcation lesions guided by intravascular ultrasound: short and midterm results of the J-REVERSE registry

AIMS

Our aim was to investigate the efficacy of the kissing balloon technique (KBT) in the provisional stenting of bifurcation lesions guided by intravascular ultrasound.

METHODS AND RESULTS

In the J-REVERSE registry, 300 non-left main bifurcation lesions in 299 patients were divided into two groups, KBT (n=163) and non-KBT (n=137). Patient and lesion characteristics were similar except for a higher prevalence of diabetic patients in the non-KBT group. The major adverse cardiac events (MACE) incidence at nine-month follow-up, including target lesion revascularisation, myocardial infarction, stent thrombosis, and death, was 6.3% in the KBT group versus 9.1% in the non-KBT group (p=0.47). Regardless of more SB dissection (10.5% vs. 1.5%, p=0.001), the KBT group obtained a greater luminal volume in the proximal main vessel (MV) (7.8±2.3 vs. 7.0±2.0 mm3/mm, p=0.006), maintained larger minimal lumen diameter at follow-up (2.73±0.43 vs. 2.63±0.39 mm, p=0.04), and demonstrated less binary side branch (SB) restenosis (9.7% vs. 21.0%, p=0.0004), which was beneficial for both true and non-true bifurcation lesions. Multivariate analysis showed the efficacy of KBT on SB restenosis (OR 0.28, 95% CI: 0.12-0.62, p=0.002).

CONCLUSIONS

Although the KBT increased SB dissection, it provided greater luminal gain in the proximal MV and SB with a similar MACE rate to non-KBT treatment up to nine-month follow-up.

In-stent Anchoring Facilitating Side-branch Balloon Delivery for Final Kissing: A Prospective, Single-center Registry Study

Background:

Recrossing the compromised side branch (SB) with a balloon is sometimes technically challenging. The aim of this study was to evaluate whether in-stent anchoring (ISA) is safe and effective to facilitate SB balloon delivery for final kissing.

Methods:

One hundred and fifty-nine consecutive patients were included (166 bifurcation lesions) in this prospective, single-center registry. ISA was used as a bailout method after unsuccessful SB crossing using conventional techniques, including low-profile balloons. Technique success was defined as SB balloon delivery and final kissing.

Results:

Kissing-balloon delivery was successfully performed with conventional strategies in 149 of 166 lesions (89.8%). In the remaining 17 lesions (10.2%), recrossing of the main vessel stent strut was not successful; therefore, ISA was attempted. The balloon successfully crossed the stent struts, and final kissing was achieved in 15 of 17 lesions (88.2%). Total final kissing was achieved in 164 of 166 lesions (98.8%), with success rates of 100% in the single-stent group and 97.6% in the two-stent group. Two cases without balloon delivery had complex bifurcation lesions with severe calcification. There was no vessel dissection in the anchoring zone.

Conclusions:

ISA is safe and effective for recrossing stent struts when conventional low-profile balloons have failed. However, large-scale trials are warranted for further evaluation.

Clinical outcome of treatment with or without a final kissing balloon technique for bifurcation in-stent restenosis lesions

BACKGROUND

The treatment strategy for in-stent restenosis (ISR) with bifurcation lesions has not been well explored. We examined the clinical outcomes between final kissing balloon technique (FKBT) after stent implantation and single-stent implantation without FKBT for bifurcation ISR lesions.

METHODS

We identified 115 consecutive ISR with bifurcation lesions among 108 patients who underwent drug-eluting stent implantation. The patients were divided into the FKBT group (34 patients, 35 lesions) and the non-FKBT group (74 patients, 80 lesions).

RESULTS

Thrombolysis in myocardial infarction flow grade of side branch was significantly greater in the patients with FKBT than those without FKBT after coronary intervention (2.80±0.46 vs. 2.65±0.68, p=0.04), but this difference was attenuated and was no longer statistically significant at the time of follow-up (2.80±0.48 vs. 2.80±0.60, p=0.97). During a mean follow-up of 47.8±23.6 months, there were no significant differences in the incidence of major adverse cardiac events (MACE). In multivariate analysis, estimated glomerular filtration rate (hazard ratio: 0.96, 95% confidence interval: 0.92-0.99, p=0.02) was an independent predictor of MACE. Contrast volume (170.71±47.17ml vs. 136.46±55.56ml, p=0.002) and radiation dose (1.44±1.65Gy vs. 0.96±0.46Gy, p=0.02) were significantly higher in the FKBT group than in the non-FKBT group.

CONCLUSIONS

Single-stent implantation without FKBT may be a sufficient treatment strategy for bifurcation ISR lesions.

Coronary bifurcation lesions treated with simple or complex stenting: 5-year survival from patient-level pooled analysis of the Nordic Bifurcation Study and the British Bifurcation Coronary Study

AIMS

Randomized trials of coronary bifurcation stenting have shown better outcomes from a simple (provisional) strategy rather than a complex (planned two-stent) strategy in terms of short-term efficacy and safety. Here, we report the 5-year all-cause mortality based on pooled patient-level data from two large bifurcation coronary stenting trials with similar methodology: the Nordic Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study: old, new, and evolving strategies (BBC ONE).

METHODS AND RESULTS

Both multicentre randomized trials compared simple (provisional T-stenting) vs. complex (culotte, crush, and T-stenting) techniques, using drug-eluting stents. We analysed all-cause death at 5 years. Data were collected from phone follow-up, hospital records, and national mortality tracking. Follow-up was complete for 890 out of 913 patients (97%). Both Simple and Complex groups were similar in terms of patient and lesion characteristics. Five-year mortality was lower among patients who underwent a simple strategy rather than a complex strategy [17 patients (3.8%) vs. 31 patients (7.0%); P = 0.04].

CONCLUSION

For coronary bifurcation lesions, a provisional single-stent approach appears to be associated with lower long-term mortality than a systematic dual stenting technique.

Correction of Stent Distortion and Overhanging Stent Struts during Left Main Bifurcation Stenting by Selective Distal Stent Cell Re-Wiring: A Novel Guidewire Approach

Stent malapposition and overhanging stent struts in front of the side branch (SB) ostium are not uncommon following bifurcation stenting that might lead to stent thrombosis. We herein present 2 cases, in which optical frequency domain imaging and intravascular ultrasound effectively revealed stent malapposition and overhanging struts inside the ostium of the SB following left main coronary artery stenting. Therefore, we introduced a novel technique for rectification of these incidental findings by selective SB re-wiring through the most distal stent cell with the adjunctive help of a double lumen microcatheter.

KEY WORDS

Distal stent strut; Left main bifurcation; Overhanging struts; Side branch re-crossing; Stent optimization.

Drug diffusion and biological responses of arteries using a drug-eluting stent with nonuniform coating

The purpose of this study was to determine the effect of a nonuniform coating, abluminal-gradient coating (AGC), which leaves the abluminal surface of the curves and links parts of the stent free from the drug coating, on the diffusion direction of the drug and the biological responses of the artery to drug-eluting stent (DES) by comparing the AGC-sirolimus stent and the conventional full-surface coating (CFC) sirolimus stent. The study aimed to verify whether the AGC approach was appropriate for the development of a safer DES, minimizing the risks of stent thrombosis due to delayed endothelialization by the drug and distal embolization due to cracking of the coating layer on the hinge parts of the DES on stent expansion. In the in vitro local drug diffusion study, we used rhodamine B as a model drug, and rhodamine B released from the AGC stent diffused predominantly into the abluminal side of the alginate artery model. Conversely, rhodamine B released from the CFC stent quickly spread to the luminal side of the artery model, where endothelial cell regeneration is required. In the biological responses study, the luminal surface of the iliac artery implanted with the AGC-sirolimus stent in a rabbit iliac artery for 2 weeks was completely covered with endothelial-like cells. On the other hand, the luminal surface of the iliac artery implanted with the CFC-sirolimus stent for 2 weeks only showed partial coverage with endothelial-like cells. While thrombosis was observed in two of the three CFC-sirolimus stents, it was observed in only one of the three AGC-sirolimus stents. Taken together, these findings indicate that the designed nonuniform coating (AGC) is an appropriate approach to ensure a safer DES. However, the number of studies is limited and a larger study should be conducted to reach a statistically significant conclusion.

Reduction in incomplete stent apposition area caused by jailed struts after single stenting at left main bifurcation lesions: micro-CT analysis using a three-dimensional elastic bifurcated coronary artery model

Stent struts protruding into ostial side branch called “jailed strut” at bifurcation lesions is a likely cause of thrombus formation. We aimed to investigate the influences of multiple kissing balloon inflation (KBI) for stent expansion, and stent platform design, respectively, on the reduction of incomplete stent apposition area (ISA area) caused by jailed struts at a side-branch ostium, using a three-dimensional elastic left main (LM) bifurcated coronary artery model. The referenced LM bifurcation angle data of 209 patients were stratified by tertiles focusing on the angle between the LM trunk (LMT) and left anterior descending artery (LAD). A bifurcation model was fabricated with angles of 129°, 122.2°, and 76.4° for LMT–LAD, LMT–left circumflex (LCx), and LAD–LCx, respectively, and with diameters of 5, 3.75, and 3.5 mm for LMT, LAD, and LCx, respectively; these diameters fulfill Murray’s law. A 75 % stenosis was included along the LMT. One-time and three-time KBIs were conducted using two-link Nobori and three-link Xience Xpedition (n = 6 each). The ISA area was quantified using micro-CT. Three-time KBI was effective in reducing the ISA area compared with one-time KBI for both the Nobori (p = 0.05) and Xience Xpedition (p = 0.07). The ISA area was smaller in the Nobori than in the Xience Xpedition, both in one-time and three-time KBI (one-time KBI: p = 0.003; three-time KBI: p = 0.001). Our findings of this study on reducing the ISA area by focusing on an interventional technique and stent design may help to improve coronary bifurcation intervention for a possibly better long-term clinical outcome.

A Novel Tram Stent Method in the Treatment of Coronary Bifurcation Lesions - Finite Element Study

A novel stent was designed for the treatment of coronary bifurcation lesion, and it was investigated for its performance by finite element analysis. This study was performed in search of a novel method of treatment of bifurcation lesion with provisional stenting. A bifurcation model was created with the proximal vessel of 3.2 mm diameter, and the distal vessel after the side branch (2.3 mm) was 2.7 mm. A novel stent was designed with connection links that had a profile of a tram. Laser cutting and shape setting of the stent was performed, and thereafter it was crimped and deployed over a balloon. The contact pressure, stresses on the arterial wall, stresses on the stent, the maximal principal log strain of the main artery and the side-branch were studied. The study was performed in Abaqus, Simulia. The stresses on the main branch and the distal branch were minimally increased after deployment of this novel stent. The side branch was preserved, and the stresses on the side branch were lesser; and at the confluence of bifurcation on either side of the side branch origin the von-Mises stress was marginally increased. The stresses and strain at the bifurcation were significantly lesser than the stresses and strain of the currently existing techniques used in the treatment of bifurcation lesions though the study was primarily focused only on the utility of the new technology. There is a potential for a novel Tram-stent method in the treatment of coronary bifurcation lesions.

Mechanism of Residual Lumen Stenosis at the Side Branch Ostium After Final Kissing Balloon Inflation: A Volumetric Intracoronary Ultrasound Study of Coronary Bifurcation Lesions

OBJECTIVES

To investigate the mechanisms of residual stenosis (RS) at side branch ostium (SBO) after final kissing balloon inflation (FKI) and clarify the impact of carina- and plaque-shifts on RS.

BACKGROUND

Carina- and plaque-shift induce SBO compromise. FKI is an effective technique to treat this complication; however, RS often persist, and are associated with restenosis at SBO.

METHODS

We performed serial volumetric analysis of 91 bifurcations in which crossover-stenting with FKI and pre-/post-intravascular ultrasounds (IVUS) were completed in both branches. The plaque- and carina-shifts were defined as an increase in the plaque-volume and a decrease in the vessel-volume at the SBO, respectively. RS at the SBO, defined as area stenosis >50% on IVUS, was identified in 19 lesions.

RESULTS

After FKI, the plaque volume- significantly increased at the SBO, with its reduction in the proximal main vessel (MV). However, at the SBO, the volumetric lumen change correlated with vessel change (ρ = 0.690, P < 0.001), but not plaque change (P = 0.390), suggesting that RS at SBO was more likely associated with inadequate vessel stretch, not plaque increase after FKI. Carina-shift was more frequently found in cases with RS, compared to those without RS (37% vs. 11%, P = 0.013). Pre-procedure IVUS findings to predict RS at SBO after FKI were negative-remodeling at distal MV, plaque -burden at distal MV, and plaque-burden at the SBO.

CONCLUSIONS

Carina-shift has a greater contribution to the formation of RS at SBO after FKI. The pre-procedure IVUS provides helpful information for predicting the RS after FKI.

Stenting of coronary bifurcation lesions: a literature and technical review

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

Approach to Treatment of Bifurcation Lesions

OPINION STATEMENT

Bifurcation lesions are frequently encountered in the cath lab [1] and remain a challenge for conventional percutaneous coronary intervention (PCI) techniques. Although provisional stenting remains the default approach for most bifurcation lesions [2-6], the two-stent technique is more appropriate in certain situations. If a two-stent strategy is selected, then final kissing balloon inflation (KBI) should be performed. Adjunctive assessment with intravascular imaging (intravascular ultrasound (IVUS)/optical coherence tomography (OCT)) and physiologic testing (fractional flow reserve, FFR) should be performed liberally. Drug-eluting stents (DES) are typically utilized to reduce the risk of restenosis in bifurcation disease.