Early effect of different bifurcation techniques on left ventricular mechanics in elective percutaneous coronary intervention

BACKGROUND

Bifurcation lesions are prevalent amongst patients with symptomatic coronary artery disease subjected to percutaneous coronary intervention (PCI). Recent consensus commends a conservative (provisional) approach when managing the side branch. Here, the aim was to explore the immediate impact of different bifurcation techniques (one stent and two stent strategies) on left ventricular LV) myocardial functions using speckle tracking echocardiography in patients subjected to elective PCI. Sixty two consecutive patients diagnosed with coronary bifurcation lesion (CBL) were enrolled. Patients were categorized into: one-stent strategy (Provisional group, n = 44) and a two-stent strategy (TAP, DK crush, or Culotte technique, n = 18), based on the coronary bifurcation site, angle, side branch diameter and Medina classification. LVEF%, regional and global longitudinal strain (GLS), and E/E' were measured before and within 24 h post PCI.

RESULTS

In both provisional and 2- stent technique, the mitral inflow velocities and mitral annular velocities showed improvement with significant reduction in E/e' (P < 0.03 and P < 0.001) respectively while LVEF% did not change. There were no significant changes in any other echo parameters post PCI. In provisional group, there were significant improvements in LAD (P < 0.001), RCA (P < 0.01) territories and GLS (P < 0.01). Δ LAD was expressively higher (34.5%) compared with Δ LCX (9.6%) and ΔRCA (25.4%), P < 0.001, P < 0.01 respectively. In the 2-stent technique group, there were significant improvements in peak longitudinal strain of LAD territory (P < 0.01), RCA territory (P < 0.01) and GLS (P < 0.01) respectively. Δ LAD territory was significantly higher in provisional group in comparison with the 2- stent technique group. Δ GLS was correlated inversely to Gensini score in provisional group and to the number of vessel diseased in 2-stent technique group.

CONCLUSION

PCI of the bifurcation lesion positively impact myocardial function. Both bifurcation techniques improve LV mechanical properties using 2D strain imaging while LV EF% remains unchanged.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Scanning Electron Microscopic Assessment of Stent Coating Integrity in Jailed Wire Technique for Bifurcation Treatment

Objectives

To assess the impact of different guidewires on stent coating integrity in jailed wire technique (JWT) for bifurcation treatment.

Background

JWT is commonly adopted to protect side branch in provisional one-stent strategy for coronary bifurcation lesions. However, this technique may cause defects in stent coatings. The degree of coating damage caused by different types of jailed wires remains unknown.

Methods

A fluid model with a bifurcation was established to mimic the condition in vivo. One-stent strategy was performed with three types of guidewire (nonpolymer-jacketed wire, intermediate polymer-jacketed wire, and full polymer-jacketed wire) tested for JWT. Scanning electron microscopy (SEM) was used to evaluate stent coating integrity and wire structure. The degrees of coating defects were recorded as no, slight, moderate, and severe defects.

Results

A total of 27 samples were tested. Analyses of SEM images showed a significant difference in the degree of coating damage among the three types of wire after the procedure of JWT (P < 0.001). Nonpolymer-jacketed wire could inevitably cause a severe defect in stent coatings, while full polymer-jacketed wire caused the least coating damages. Besides, there were varying degrees of coil deformation in nonpolymer-jacketed wires, while no surface damage or jacket shearing was observed in full polymer-jacketed wires.

Conclusions

Although nonpolymer-jacketed wire has long been recommended for JWT, our bench-side study suggests that full polymer-jacketed wire may be a better choice. Further clinical studies are needed to confirm our findings.

[Use of drug-coated balloons for interventions on bifurcation lesions of coronary arteries]

Interventions on bifurcation lesions of the coronary bed are one of the most complicated tasks of interventional cardiology. Recent trends are toward active study of using drug-eluting balloons for interventions in this type of lesions. Using such technique makes it possible to minimize the risks associated with implantation of stents in sites of coronary artery bifurcations with good angiographic results. This article is a review of the literature data concerning the use of drug-coated balloons in interventions on bifurcation lesions of the coronary bed, discussing peculiarities of the balloon catheter design, dynamics of delivery of an antiproliferative drug to the vascular wall. This is followed by considering the experience with using innovative sirolimus-coated balloon catheters, as well as future perspectives of these devices for interventions in coronary artery bifurcation lesions.

Percutaneous management of coronary bifurcation lesions: current perspective

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Long-term treatment effect and adverse events of a modified jailed-balloon technique for side branch protection in patients with coronary bifurcation lesions

Background

Percutaneous coronary interventions (PCI) of bifurcation lesions is technically challenging and associated with lower success rates and higher frequency of adverse outcomes. In the present study, we aimed to evaluate the immediate and long-term treatment effect and adverse events of a new modified jailed-balloon technique on side branch (SB) during PCI on coronary bifurcation lesions.

Methods

This was a prospective study of 60 patients (49 males, 11 females, mean age 66 ± 10 years) with coronary bifurcation lesions treated at the Beijing Hospital between September 2014 and October 2015. They underwent main vessel (MV) stenting and modified jailed-balloon technique on the SB. All patients were followed with hospital visits at 9 months. Angiographic success, major adverse cardiac events (MACE), SB occlusion, and angina were evaluated.

Results

The majority of the patients had acute coronary syndrome (91.7%) and Medina 1.1.1. bifurcation lesions (71.7%). After MV stenting, thrombolysis in myocardial infarction (TIMI) 3 flow was established 100% of MV and 93.3% of SB. No SB occlusion occurred. The jailed SB balloon and wire could be successfully removed in all patients without damage or entrapment. The majority (91.7%) of patients achieved Canadian Cardiovascular Society I stage. There was no MACE during in-hospital stay and 9-month follow-up.

Conclusion

The modified JBT provided high rate of procedural success, excellent SB protection during MV stenting, and excellent immediate and long-term clinical outcomes.

A randomized trial comparing two stent sizing strategies in coronary bifurcation treatment with bioresorbable vascular scaffolds - The Absorb Bifurcation Coronary (ABC) trial

BACKGROUND

Limited information is available on the use of Bioresorbable Vascular Scaffold (BVS) in bifurcations involving significant side branches. When treating bifurcation disease with metal stents, the recommendation is to choose a stent diameter based on the distal main vessel diameter. Whether this sizing strategy is applicable to BVS is currently unknown.

METHODS

We randomised 37 patients undergoing elective PCI for 'false' bifurcation disease (Medina 0,1,0; 1,0,0; 1,1,0) to receive BVS based either on proximal or distal reference diameters. Optical Frequency Domain Imaging (OFDI) measurements were performed pre BVS insertion to obtain proximal and distal reference diameters and post implantation. BVS size was chosen according to the proximal or distal reference diameter as per randomisation. Implantation was performed using the PSP technique tailored to bifurcation stenting. OFDI was repeated post implantation to confirm satisfactory expansion and apposition.

RESULTS

Baseline demographics between the two groups were similar. Patients were aged 62.8 ± 3.3 years; 76% were male. Mean side branch diameter was 2.24 ± 0.13 mm. TIMI III flow in the main vessel was achieved in all cases. Side branch occlusion occurred in 1 case (2.7%). In the distal-sizing arm, there was a greater incidence of significant malapposition (>300 μm) at the proximal end of the scaffold on OCT (2.3% versus 0.8%, p 0.023). The incidence of distal edge dissections was numerically greater in the proximal-sizing group but this was not statistically significant (31.3% vs 11.8%, p 0.17).

CONCLUSION

Both proximal and distal sizing strategies have similar procedural complication rates when using the ABSORB BVS to treat coronary bifurcations. However a proximal sizing strategy is associated with less malapposition and may be preferable.

A randomized trial of bifurcation stenting technique in chronic total occlusions percutaneous coronary intervention

BACKGROUND

The optimal strategy to treat bifurcation lesions (BFLs) in a percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs) remains unknown.

AIMS

We sought to assess whether T-provisional or mini-crush is appropriate for BFLs within CTO vessels.

PATIENTS AND METHODS

From January 2011 to December 2013, patients who underwent successful CTO guidewire crossing and with a BFL within the CTO target vessel were enrolled prospectively and assigned randomly to either T-provisional stenting or the mini-crush technique for BFL treatment. One-year clinical follow-up was performed. Major adverse cardiac and cerebrovascular events (MACCE) were defined as the composite of cardiovascular death, myocardial infarction, target vessel revascularization, and stroke.

RESULTS

The prevalence of BFLs was 54.3%. A total of 146 patients with BFLs within CTO vessel were enrolled prospectively and assigned randomly to either T-provisional stenting (N=73) or the mini-crush technique (N=73). Angiographic and clinical success rates were similar in the two groups: 91.8 versus 97.2% (P=0.27) and 91.8 versus 94.5% (P=0.67), respectively.Although T-provisional stenting was associated with a nonsignificantly lower incidence of MACCE in case of BFLs located far from the CTO (9.3 vs. 22.2%; P=0.426), the mini-crush technique resulted in higher MACCE-free survival at 1 year in the presence of BFLs within the CTO body or close to the proximal or the distal cap (89.1 vs. 64.9%; P=0.007).

CONCLUSION

The mini-crush technique appeared to be associated with improved 1-year clinical and angiographic outcomes, particularly when used to treat BFLs located within the CTO body or close to the proximal or the distal cap.

Single- Versus 2-Stent Strategies for Coronary Bifurcation Lesions: A Systematic Review and Meta-Analysis of Randomized Trials With Long-Term Follow-up

Background

The majority of coronary bifurcation lesions are treated with a provisional single‐stent strategy rather than an up‐front 2‐stent strategy. This approach is supported by multiple randomized controlled clinical trials with short‐ to medium‐term follow‐up; however, long‐term follow‐up data is evolving from many data sets.

Methods and Results

Meta‐analysis of randomized controlled trials evaluating long‐term outcomes (≥1 year) according to treatment strategy for coronary bifurcation lesions. Nine randomized controlled trials with 3265 patients reported long‐term clinical outcomes at mean weighted follow‐up of 3.1±1.8 years. Provisional single stenting was associated with lower all‐cause mortality (2.94% versus 4.23%; risk ratio: 0.69; 95% confidence interval, 0.48–1.00; P=0.049; I²=0). There was no difference in major adverse cardiac events (15.8% versus 15.4%; P=0.79), myocardial infarction (4.8% versus 5.5%; P=0.51), target lesion revascularization (9.3% versus 7.6%; P=0.19), or stent thrombosis (1.8% versus 1.6%; P=0.28) between the groups. Prespecified sensitivity analysis of long‐term mortality at a mean of 4.7 years of follow‐up showed that the provisional single‐stent strategy was associated with reduced all‐cause mortality (3.9% versus 6.2%; risk ratio: 0.63; 95% confidence interval, 0.42–0.97; P=0.036; I²=0).

Conclusions

Coronary bifurcation percutaneous coronary intervention using a provisional single‐stent strategy is associated with a reduction in all‐cause mortality at long‐term follow‐up.

True double bifurcation lesions: new application of the self-expandable Axxess stent and review of literature with dedicated bifurcation devices

Complex coronary artery bifurcation lesions occurred in hard clinical scenarios, such as acute coronary syndromes, may represent a challenge for interventional cardiologists, with not-defined general consensus on treatment. Even if provisional stenting is the most common option used to restore rapidly the coronary branches flow, improvements in industrial technologies and design of new dedicated bifurcation devices might open new modalities of treatment in these complex cases. The Axxess stent (Biosensors Europe SA, Morges, Switzerland) is a self-expanding biolimus-eluting conical V-shape stent, specifically designed to treat "easily" coronary artery bifurcation lesions, with reported favorable long-term clinical results in stable patients compared to a provisional technique. We report for the first time the feasibility to use this device in a case of "true double coronary bifurcation lesion" occurred in the context of acute coronary syndrome. Moreover, we reviewed studies with bifurcation dedicated devices and available cases of "true double bifurcation lesions", underlying advantages/disadvantages of using one device over the others during acute coronary syndrome.

The EBC TWO Study (European Bifurcation Coronary TWO): A Randomized Comparison of Provisional T-Stenting Versus a Systematic 2 Stent Culotte Strategy in Large Caliber True Bifurcations

BACKGROUND

For the treatment of coronary bifurcation lesions, a provisional strategy is superior to systematic 2-stent techniques for the most bifurcation lesions. However, complex anatomies with large side branches (SBs) with significant ostial disease length are considered by expert consensus to warrant a 2-stent technique upfront. This consensus view has not been scientifically assessed.

METHODS AND RESULTS

Symptomatic patients with large caliber true bifurcation lesions (SB diameter ≥2.5 mm) and significant ostial disease length (≥5 mm) were randomized to either a provisional T-stent strategy or a dual stent culotte technique. Two hundred patients aged 64±10 years, 82% male, were randomized in 20 European centers. The clinical presentations were stable coronary disease (69%) and acute coronary syndromes (31%). SB stent diameter (2.67±0.27 mm) and length (20.30±5.89 mm) confirmed the extent of SB disease. Procedural success (provisional 97%, culotte 94%) and kissing balloon inflation (provisional 95%, culotte 98%) were high. Sixteen percent of patients in the provisional group underwent T-stenting. The primary end point (a composite of death, myocardial infarction, and target vessel revascularization at 12 months) occurred in 7.7% of the provisional T-stent group versus 10.3% of the culotte group (hazard ratio, 1.02; 95% confidence interval, 0.78-1.34; P=0.53). Procedure time, x-ray dose, and cost all favored the simpler procedure.

CONCLUSIONS

When treating complex coronary bifurcation lesions with large stenosed SBs, there is no difference between a provisional T-stent strategy and a systematic 2-stent culotte strategy in a composite end point of death, myocardial infarction, and target vessel revascularization at 12 months.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT 01560455.

Percutaneous coronary intervention of bifurcation lesions and platelet reactivity

BACKGROUND

Although bifurcation percutaneous coronary intervention (PCI) is associated with lower procedural success rates and higher risk of complications, there are little data regarding outcomes after successful bifurcation PCI with contemporary stents and techniques. Whether residual platelet reactivity (PR) affects outcomes differently after bifurcation versus non-bifurcation PCI is also unknown. We studied the association between bifurcation PCI, PR, and clinical outcomes among patients undergoing successful PCI with drug-eluting stents.

METHODS

Patients in the prospective, multicenter ADAPT-DES study were stratified according to whether they underwent bifurcation PCI. Two-year outcomes were compared between groups using Cox proportional hazards models. Target vessel failure (TVF) was defined as the composite of all-cause death, myocardial infarction, and ischemia-driven target vessel revascularization.

RESULTS

Among the 8582 patients included in ADAPT-DES, 1276 (15%) had bifurcation PCI. Bifurcation PCI was independently associated with increased risk of TVF (adjusted hazard ratio [HR] 1.26, 95% confidence interval [CI] 1.08-1.46, p=0.003), driven by higher risk of myocardial infarction (5.9% vs. 4.6%, p=0.033) and ischemia-driven target vessel revascularization (13.0% vs. 9.2%, p<0.0001). There was no statistical interaction between PR and bifurcation PCI regarding TVF risk (adjusted p_interaction=0.87). Stenting of both bifurcation branches was associated with the highest risk of TVF (adjusted HR 1.91, 95% CI 1.48-2.46 versus non-bifurcation PCI; p_trend<0.001).

CONCLUSIONS

Bifurcation PCI is associated with a higher risk of 2-year adverse ischemic events than non-bifurcation PCI, a risk that is particularly high when both bifurcation branches are stented, and with HPR conferring similar risk for bifurcation and non-bifurcation PCI.

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.

Percutaneous Coronary Intervention for Bifurcation: How Can We Outperform the Provisional Strategy?

In the era of drug-eluting stents, the provisional stenting strategy has been established as the default strategy in percutaneous coronary intervention for bifurcation lesions. However, emerging evidence shows that, in selected situations, the complex strategy of stenting both vessels regardless could reduce side-branch restenosis without penalty. In particular, the double kissing crush technique has been proven to outperform the provisional strategy and other complex strategies in randomized trials. In this review, we present the evidence comparing the 2 strategies and individual stenting techniques and discuss the roles of other optimization techniques such as final kissing balloon inflation, proximal optimization technique, intravascular ultrasonography, and optical coherence tomography. Finally, we suggest a practical approach for choosing the optimal strategy for intervention with coronary bifurcation lesions.

Absorb Bioresorbable Vascular Scaffold in Complex Coronary Bifurcation Interventions: Insights From an In Vivo Multimodality Imaging Study

BACKGROUND

Although bioresorbable scaffolds offer potential advantages compared with metallic drug-eluting stents in the treatment of complex coronary bifurcation lesions, there are concerns that the polymeric scaffold integrity may be compromised. This in vivo study sought to provide insights about the feasibility of performing complex bifurcation stenting with Absorb bioresorbable vascular scaffolds (Abbott Vascular, Santa Clara, CA).

METHODS AND RESULTS

Twenty New Zealand white rabbits underwent stenting of the nondiseased aortoiliac bifurcation with bioresorbable vascular scaffolds using provisional (PS, n=5), culotte (n=5), modified-T (n=5), or T-and protrusion (n=5) stenting techniques. Angiography, optical coherence tomography, and microcomputed tomography were performed. Angiographic results were excellent without evidence of dissection or side branch (SB) compromise. PS optimally opened the SB ostium without deforming the main vessel (MV) bioresorbable vascular scaffolds, avoiding malapposition, and revealing a single connector fracture in 1 of 5 cases on microcomputed tomography. Culotte stenting resulted in complete bifurcation coverage with extensive segments of double-layered struts and inappropriately apposed struts at the bifurcation level in 3 of 5 cases. On microcomputed tomography, there was MV and SB scaffold distortion at the bifurcation with single strut fractures in 4 of 5 and double fractures in 1 of 5. Modified-T and T-and protrusion resulted in complete bifurcation coverage and in minimal double-strut layers at the neocarina. On microcomputed tomography, no strut fractures were present after modified-T, whereas in 3 of 5 T-and protrusion procedures single strut fractures were noted.

CONCLUSIONS

Bifurcation stenting using bioresorbable vascular scaffolds is feasible with excellent angiographic results. PS with additional T-and protrusion whenever needed seems a reasonable approach. Whenever a 2-stent technique is planned, modified T-stenting appears the most promising.

Extended use of the GuideLiner in complex coronary interventions

AIMS

Challenging coronary anatomies including chronic total occlusions (CTO), extreme vessel tortuosity, diseased bypass grafts, and anomalous coronary arteries pose difficulties in coronary interventions. The GuideLiner is a monorail catheter originally developed to facilitate delivery of stents to target lesions in tortuous vessels. We conducted a study on the feasibility and safety of utilising this catheter in a wider array of complex coronary interventions.

METHODS AND RESULTS

Consecutive patients undergoing coronary or peripheral interventions where a GuideLiner was used were recruited into this study. Patient demographics, lesion and vessel characteristics, procedural details and outcomes were prospectively entered into our database and analysed. From September 2009 to October 2011, 54 consecutive patients underwent coronary intervention in our institution using a GuideLiner; 21 out of 54 coronary applications were motivated by the need to increase support to cross CTOs, predominantly of the RCA. Anomalous or angulated take-off of the treatment vessels (31%), previously deployed proximal stents (15%), heavy proximal calcification (9%) and tortuosity (7%) accounted for the remaining reasons. One patient had successful renal denervation with the aid of a GuideLiner catheter. Procedural success was 98% in our series with no device-related periprocedural complications such as ostial dissection or myocardial necrosis.

CONCLUSIONS

The use of a GuideLiner facilitates the approach to complex coronary interventions including chronic total occlusion and saphenous vein graft intervention by providing greater back-up support and easier engagement of coronary ostia.

A Novel-Modified Provisional Bifurcation Stenting Technique: Jailed Semi-Inflated Balloon Technique

OBJECTIVE

We proposed a new technique for the treatment of coronary bifurcation lesions, called jailed semi-inflated balloon technique (JSBT).

BACKGROUND

Currently, provisional approach is recommended to treat most of coronary bifurcation lesions. However, it is associated with the risk of side branch (SB) occlusion after main vessel (MV) stenting due to plaque or carina shift into the SB. The SB occlusion may cause peri-procedural myonecrosis or hemodynamic compromise. Therefore, strategies are needed to reduce the SB occlusion during provisional approach.

METHODS

Between September 2014 and April 2015, we selected 137 patients (104 male, 33 female; mean age 63.6 ± 11.7 years) with 148 distinct coronary bifurcation lesions underwent percutaneous coronary intervention using JSBT. All patients were followed with hospital visits or telephone contact up to 1 month.

RESULTS

The majority of the patients had acute coronary syndrome (64.2%) and Medina 1.1.1. bifurcation lesions (62.8%). The lesion localization was distal left main (LM) coronary artery in 28 patients. After the MV stenting, thrombolysis in myocardial infarction (TIMI) 3 flow was established in 100% of both MV and SB. There was no SB occlusion in any patient. There was no major adverse cardiac event during in-hospital stay and 1 month follow-up.

CONCLUSIONS

The JSBT technique can be successfully performed in both LM and non-LM bifurcation lesion. This technique provides high rate of procedural success, excellent SB protection during MV stenting and excellent immediate clinical outcome.

3D optical coherence tomography: new insights into the process of optimal rewiring of side branches during bifurcational stenting

AIMS

We describe three-dimensional optical coherence tomography (3D-OCT) guided bifurcation stenting and the clinical utility of 3D-OCT.

METHODS AND RESULTS

Twenty-two consecutive patients who underwent OCT examination to confirm the recrossing position after stent implantation in a bifurcation lesion were enrolled. Frequency domain OCT images were obtained to check the recrossing position and 3D reconstructions were performed off-line. The recrossing position was clearly visualised in 18/22 (81.8%) cases. In 13 cases, serial 3D-OCT could be assessed both before and after final kissing balloon post-dilation (FKBD). We divided these cases into two groups according to the presence of the link between hoops at the carina: free carina type (n=7) and connecting to carina type (n=6). All free carina types complied with the distal rewiring. The percentage of incomplete stent apposition (%ISA) of free carina type at the bifurcation segment after FKBD was significantly smaller than that of the connecting to carina type (0.7±0.9% vs. 12.2±6.5%, p=0.0074).

CONCLUSIONS

3D-OCT confirmation of the recrossing into the jailed side branch is feasible during PCI and may help to achieve distal rewiring and favourable stent positioning against the side branch ostium, leading to reduction in ISA and potentially better clinical outcomes.

A Y-shaped bifurcation-dedicated stent for the treatment of de novo coronary bifurcation lesions: an IVUS analysis from the BRANCH trial

AIMS

The aim of this IVUS substudy was to assess the efficacy of the Y-shaped Medtronic bifurcation-dedicated stent (BDS) for the treatment of de novo coronary bifurcated lesions.

METHODS AND RESULTS

In the BRANCH trial, post-procedure IVUS was performed in 45 patients. IVUS was available in both branches in 19 lesions and only the main branch (MB) in 26 lesions. IVUS analysis included four distinct locations: proximal MB, bifurcation site, distal MB, and side branch (SB). Lumen symmetry was calculated as minimum/maximum lumen diameters. The quantity of isolated stent struts across the SB ostium was used to assess inadequate strut apposition to the carina resulting in partial jailing of the SB orifice. A minimum stent area (MSA) <4 mm2 was found in 0% of proximal and distal MB, and in 15.4% of SB. In SB, MSA was located mainly at mid or distal segments (84.6%), rather than at the SB ostium. Eccentric stent expansion and edge dissection were seen primarily at proximal MB. Isolated struts were seen in only 20.9% of SB ostia with a minimum length of 0.7±0.4 mm.

CONCLUSIONS

Implantation of BDS resulted in adequate stent dimensions and strut apposition at the carina and SB ostium. ClinicalTrials.gov Identifier: NCT00607321.

The utility of stent enhancement to guide percutaneous coronary intervention for bifurcation lesions

AIMS

Percutaneous coronary intervention (PCI) of bifurcation lesions is complex and is technically very demanding. Coronary angiography is considered the gold standard method to guide PCI but has several limitations. The purpose of this study was to determine the utility of stent enhancement with StentBoost® (StB), a novel fluoroscopic imaging technique, and its potential role during bifurcation PCI.

METHODS AND RESULTS

This prospective study included 97 patients who underwent bifurcation PCI (98 bifurcations), using StB. Bifurcation lesions were classified according to the modified Medina classification. StB was performed in all patients to obtain improved stent visualisation and to detect optimal release and deployment. Therefore, three groups were formed, according to the quality of image: optimal visualisation, suboptimal visualisation and poor visualisation. Most of the bifurcation disease involved the main vessel (99%) and in 80 patients (81.6%) there was side branch involvement. Most bifurcations had both main vessel and side branch lesions (Medina 1,1,1) (70 patients, 71.4%). StB image quality was good in 79.6% of the cases (optimal visualisation of the stent and guidewire), was suboptimal in 19.4%, and poor in 1% (overlapping of structures or devices). In three cases, StB enabled the identification of the guidewire and angioplasty balloon passing outside stent borders during rewiring of the side branch.

CONCLUSIONS

Imaging techniques have a primary role during bifurcation PCI. StentBoost is a simple and quick method that offers several advantages, enabling improved stent visualisation, appropriate rewiring of the side branch, adequate stent expansion and optimal apposition of the struts to the wall.

Assessment of side branch predilation before a provisional T-stent strategy for bifurcation lesions. A randomized trial

BACKGROUND

A simple approach is the predominant strategy for the percutaneous coronary intervention of bifurcation lesions. Performing side branch (SB) predilation in this context is currently a matter of controversy. In this study, we assess the efficacy of SB predilatation before a provisional T-stent strategy for bifurcation lesions.

METHODS

Between February 2009 and November 2012, 372 patients with true bifurcation lesions were randomized to either predilation of the SB (n = 187) or no predilatation (n = 185) before main branch (MB) stent implantation and a subsequent SB provisional stent strategy.

RESULTS

There were no significant differences between the patient groups regarding the baseline characteristics. After MB stent implantation, the TIMI flow of the SB was higher in the patients with SB predilation: TIMI flow 0 to 1; 2 (1%) versus 18 (10%), P < .001; and TIMI flow III; 179 (96%) versus 152 (82%), P < .001. Side branch stenting rates were 4% versus 3%, P = not significant. In addition, 60 patients (32%) from the SB predilation group presented SB residual stenosis by visual inspection <50%, and TIMI flow ≥III did not require any additional treatment. The failure rate of SB rewiring, the time of rewiring, the number of wires used, and the incidence of major events were similar in both groups of patients.

CONCLUSIONS

Predilation of the SB resulted in improved TIMI flow after MB stenting and less indication to subsequently treat the SB. If rewiring of the SB is required, predilation did not hinder this maneuver.

Serial intravascular ultrasound observations from the Tryton first-in-man study

AIMS

To report serial intravascular ultrasound (IVUS) findings of bifurcation lesions treated with the dedicated Tryton Side Branch Stent to assess mechanisms of restenosis.

METHODS AND RESULTS

The Tryton FIM study was a multicentre, prospective, single-arm, "first-in-man" study to treat de novo bifurcation lesions. Minimum lumen area (MLA) sites and overall volumes were analysed within main vessels and side branches. Overall, 27 main vessels and 22 side branches had paired baseline and follow-up IVUS. The post-intervention main vessel MLA decreased from 5.3 (4.1, 6.2) to 4.8 (3.4, 5.7) mm2 at follow-up, p=0.02, and the side branch MLA decreased from 3.5 (3.0, 3.8) to 2.5 (2.2, 3.2) mm2, p=0.0005. Stent area at the side branch did not change (mean stent area from 4.0 [3.3, 4.1] to 3.8 [3.4, 4.2] mm3/mm, p=0.95). Neointimal hyperplasia (NIH) net volume obstruction (%) measured 1.8% (0.5, 7.0) for the entire main vessel and 14.9% (2.3, 31.1) for the entire side branch stents. In both main vessel and side branches the decrease in lumen area correlated significantly with NIH.

CONCLUSIONS

Serial IVUS analysis of a new side branch Tryton stent showed no chronic stent recoil. Side branch underexpansion was common and along with superimposed NIH contributed to the reduction in lumen dimensions at follow-up.

Dedicated two-stent technique in complex bifurcation percutaneous coronary intervention with use of everolimus-eluting stents: the EES-bifurcation study

OBJECTIVES

To compare the outcomes of initial one-stent (1S) versus dedicated two-stent (2S) strategies in complex bifurcation percutaneous coronary intervention (PCI) using everolimus-eluting stents (EES).

BACKGROUND

PCI of true bifurcation lesions is technically challenging and historically associated with reduced procedural success and increased restenosis. Prior studies comparing initial one-stent (1S) versus dedicated two-stent (2S) strategies using first-generation drug-eluting stents have shown no reduction in ischemic events and more complications with a 2S strategy.

METHODS

We performed a retrospective study of 319 consecutive patients undergoing PCI at a single referral center with EES for true bifurcation lesions, defined by involvement of both the main vessel (MV) and side branch (SB). Baseline, procedural characteristics, quantitative coronary angiography and clinical outcomes in-hospital and at one year were compared for patients undergoing 1S (n=175) and 2S (n=144) strategies.

RESULTS

Baseline characteristics were well-matched. 2S strategy was associated with greater SB acute gain (0.65±0.41 mm vs. 1.11±0.47 mm, p<0.0001). In-hospital serious adverse events were similar (9% with 2S vs. 8% with 1S, p=0.58). At one year, patients treated by 2S strategy had non-significantly lower rates of target vessel revascularization (5.8% vs. 7.4%, p=0.31), myocardial infarction (7.8% vs. 12.2%, p=0.31) and major adverse cardiovascular events (16.6% vs. 21.8%, p=0.21).

CONCLUSION

In this study of patients undergoing PCI for true coronary bifurcation lesions using EES, 2S strategy was associated with superior SB angiographic outcomes without excess complications or ischemic events at one year.

Overview of Technical and Cost Considerations in Complex Percutaneous Coronary Intervention

Complex percutaneous coronary intervention (PCI), encompassing an ever-expanding range of challenging lesion sets and patient populations, accounts for a significant proportion of PCI procedures being performed currently. Specific lesion types associated with lower rates of procedural success and higher rates of recurrence or major adverse cardiac events (MACE) include multivessel disease, unprotected left main coronary artery disease, fibrocalcific or undilatable lesions, chronic total occlusions, degenerated saphenous vein graft lesions, thrombotic lesions, and bifurcation disease. Validated tools and technical strategies currently exist to address most procedural scenarios encountered and should be familiar to the complex PCI operator. Anticipated clinical outcomes, projected resource utilization, and cost considerations should all factor into the decisions of when, how, and in whom to intervene.

Recent perspective on coronary artery bifurcation interventions

Coronary bifurcation lesions are frequent in routine practice, accounting for 15-20% of all lesions undergoing percutaneous coronary intervention (PCI). PCI of this subset of lesions is technically challenging and historically has been associated with lower procedural success rates and worse clinical outcomes compared with non-bifurcation lesions. The introduction of drug-eluting stents has dramatically improved the outcomes. The provisional technique of implanting one stent in the main branch remains the default approach in most bifurcation lesions. Selection of the most effective technique for an individual bifurcation is important. The use of two-stent techniques as an intention to treat is an acceptable approach in some bifurcation lesions. However, a large amount of metal is generally left unapposed in the lumen with complex two-stent techniques, which is particularly concerning for the risk of stent thrombosis. New technology and dedicated bifurcation stents may overcome some of the limitations of two-stent techniques and revolutionise the management of bifurcation PCI in the future.

Evaluating stent optimisation technique (StentBoost®) in a dedicated bifurcation stent (the Tryton™)

BACKGROUND/PURPOSE

To evaluate the use of StentBoost® in the Tryton™ dedicated SideBranch Stent.

METHODS & RESULTS

The Tryton™ SideBranch Stent has been effectively used to manage complex bifurcations. However, the paucity of scaffolding in the proximal part of the stent makes it often difficult to visualise under standard radiographic imaging. We set out to evaluate whether by using an augmented radiographic imaging technique it was possible to aid visualisation of the stent. In particular the so call 'wedding ring' band which is crucial to the procedural success. We further evaluated whether it was possible to determine the apposition of the stent at the carina, its coverage and the ability to aid recrossing of the struts closest to the carina as well as the added radiation exposure.

CONCLUSIONS

StentBoost® was found to be invaluable to the procedural success of the Tryton™ deployment without adding any extra cost to the procedure and with only a 3.7% increase in radiation to the patient. It allowed enhanced visualisation in all cases to aid apposition, recrossing and coverage.

Paclitaxel drug-coated balloons: a review of current status and emerging applications in native coronary artery de novo lesions

The paclitaxel drug-coated balloon (DCB) is an emerging device in percutaneous coronary intervention, which has shown promising results by means of a high-concentration, rapid local release of an antirestenotic drug without the use of a durable polymer or metal scaffold. DCB have already proven effective in clinical trials for the treatment of in-stent restenosis. Its coronary applications may potentially be widened to a host of complex coronary de novo lesion subsets, such as small-caliber vessels, diabetes, and diffuse lesions, where the use of stents may be hampered by suboptimal results. Recently, this technology has rapidly evolved with newer studies added to assess the value of DCB in coronary applications other than in-stent restenosis. We present a review of the role of DCB in de novo coronary lesions based on this latest clinical evidence.

A provisional strategy for treating true bifurcation lesions employing a scoring balloon for the side branch: final results of the AGILITY trial

BACKGROUND

The provisional approach for bifurcation stenting with side-branch balloon angioplasty is associated with dissections and suboptimal results requiring kissing balloon techniques or bailout stenting. We hypothesized that using a scoring balloon for the side branch and a drug-eluting stent for the main vessel might improve outcomes of true bifurcation lesions.

METHODS AND RESULTS

A total of 93 patients with complex bifurcations were enrolled in a multicenter, single-arm, prospective clinical trial. A drug-eluting stent was deployed in the main vessel following dilatation of the side-branch stenosis with a scoring balloon. The overall angiographic success rate was 93.5%, and procedural success rate was 91.4%. The final diameter stenosis was 13.9% ± 7.2% for the main vessel and 33.3% ± 22.9% for the side branch. Crossover to stent deployment in the side branch was required in 10.8%. The postscoring balloon dissection rate was 8.2% and 6% (all ≤ class C) for the main vessel and side branch respectively, which was reduced to 1.1 and 2.1% poststenting. At 9-month follow-up, the composite MACE rate [cardiac death, myocardial infarction, or target lesion revascularization (TLR)] was 5.4%, including a TLR rate of 3.3% (1.1% from hospital discharge to 9 months).

CONCLUSION

The 9-month results of the AGILITY trial support a simple provisional strategy for treating complex true bifurcation lesions with deployment of a drug-eluting stent in the main vessel after dilatation of the side-branch vessel with a scoring balloon. This strategy was associated with excellent and safe procedural results, a low rate of crossover to side-branch stenting, and favorable outcomes.

Bifurcation stenting after failed angioplasty of infrapopliteal arteries in critical limb ischemia: techniques and short-term follow-up

OBJECTIVES

To report on the efficacy of drug eluting stents (DES) in below the knee lesions involving arterial bifurcations after failed angioplasty.

BACKGROUND

DES have become a mainstay in the treatment of below the knee lesions. However, little is known about the efficacy of DES in infrapopliteal lesions involving the arterial bifurcations. This is the first report on the endovascular treatment of below-the knee bifurcations.

METHODS

11 patients with critical lower limb ischemia and complex infrapopliteal atherosclerotic disease underwent provisional DES placement in infrapopliteal bifurcation lesions. Clinical and angiographic follow-up data were prospectively collected in all patients.

RESULTS

Technical success was achieved in all cases. After 6 months, the two vessel primary patency (2VPP) rate was 54.5% and the 1VPP rate was 81.8%. Between baseline and the follow-up, mean ankle-brachial index increased from 0.31 ± 0.10 to 0.68 ± 0.16, and mean Rutherford-Becker class decreased from 4.73 ± 0.20 to 3.00 ± 1.41 (P < 0.001 for both comparisons).

CONCLUSIONS

Bifurcation stenting techniques, that are described for the coronary arteries can be also performed in the infrapopliteal arteries. However, early reocclusion was frequent in this case series, when stenting was performed in a bail-out setting. If balloon angioplasty alone leads to no sufficient results in bifurcation lesions, a single stent strategy could also be considered.

Optical coherence tomography for guidance of distal cell recrossing in bifurcation stenting: choosing the right cell matters

AIMS

The aim of this study was to assess the ability of optical coherence tomography (OCT) to guide recrossing during percutaneous coronary interventions in bifurcations and to reduce strut malapposition.

METHODS AND RESULTS

Fifty-two patients undergoing elective treatment of bifurcation lesions using provisional stenting as default strategy were included in the study. Patients were divided into two groups: OCT-guided stent recrossing (group 1, n=12), and angiography-guided recrossing (group 2, n=40). Malapposition in the various bifurcation segments was compared in the two groups, using propensity score analysis to correct for confounders. In 4/12 patients (33%) of the OCT-guided group after the first attempt to recross the stent towards the SB the wire was found to have crossed in a proximal cell, requiring a second and in one case a third attempt to successfully cross through a distal cell. Patients who were treated using OCT-guided recrossing had a significantly lower number of malapposed stent struts, especially in the quadrants towards the SB ostium (9.5%[7.5-17.4%] vs 42.3%[31.2-54.7%] in the angiography-guided group, p<0.0001).

CONCLUSIONS

The rate of strut malapposition was significantly reduced when OCT was used to confirm that wire recrossing was performed in a distal cell of the SB ostium.