Extension Distance Mismatch—An Unrecognized Factor for Suboptimal Side Branch Ostial Coverage in Bifurcation Lesion Stenting

Background: The unsatisfactory side branch (SB) ostial strut coverage remains a problem in coronary bifurcation stenting. Both the surplus and lack of struts at SB ostium may be the causative mechanism. We propose that the inability of available stents to cover the “extension distance” of the bifurcation region is the cause of in‐stent restenosis. Methods: The extension distance (ED) is defined as the maximal distance at the carina tip, which must be covered by the stent struts to ensure optimal coverage of the main branch (MB) and SB openings. A mathematical model was created, representing the key factors that govern geometrical reconfigurations after stent implantation in bifurcations. There are two options—with and without bifurcation region deformation. The theoretical assumptions were tested on a bifurcation model (soft polyvinylchloride polymer tubes) permitting free wall deformations and the following parameters: Parent Vessel, MB, SB diameters of 3.5, 3.0, and 2.5 mm, respectively, with an angle of 45° between the MB and SB. After stenting, final KBI with 3.5 mm and 3.0 mm balloons was performed up to 20 atm. Results: After the carina displacement, the ED, which has to be covered, is considerably smaller if the suboptimal result (DS >50%) at the SB ostium is acceptable. The maximal EDs from the bench test measurements are: Vision, Abbott Vascular – 5.62 mm ± 0.04; Liberte, Boston Scientific Corp. – 5.2 mm ± 0.03; Chopin2, Balton – 4.58 mm ± 0.05; Volo, Invatec – 4.41 mm ± 0.04; Driver, Medtronics – 4.39 mm ± 0.04; BxSonic, Cordis, J&J – 4.48 mm ± 0.05. The theoretical maximal ED of the model is 6.91 mm—28–62% larger than actually observed with different stents. Conclusions: The achievement of perfect ostial coverage of the SB is unsatisfactory with most of the currently available stents, especially when poststenting excessive dilation of the ostium of the SB is performed. (J Interven Cardiol 2010;23:305–318)     

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. (J Interven Cardiol 2015;28:420–429)

     

Contradictory Shear Stress Distribution Prevents Restenosis after Provisional Stenting for Bifurcation Lesions

Background: Endothelial shear stress is one of the local hemodynamic factors suspected in the development of coronary atherosclerosis in bifurcation lesions. In patients with provisional stenting, the endothelial shear stress (SS) distribution is unknown. Objective: The aim of this study was to investigate the magnitude and distribution of the SS of coronary bifurcation lesions stenting by the provisional approach. Methods: Ten consecutive patients were included in this study. Quantitative coronary analysis, flow study, and three‐dimensional computational analysis with the aid of the commercial software CD STAR‐CCM+ were done before and after the provisional stenting procedure and also 8 months later. Results: Clinical and angiographic follow‐up were available in all patients. No patient had a side branch (SB) stent. At the 8‐month follow‐up, no major adverse cardiac event (MACE) occurred. There was also no clinical and angiographic restenosis. Before PCI, the distal main vessel (MV)‐lateral, and the SB‐lateral subsegments had relative nonsignificant lower SS value (4.08 ± 2.78 Pa and 4.35 ± 5.04 Pa, respectively) when compared to other segments. After 8‐month follow‐up, sustained decreased SS value was shown in the distal MV‐lateral segment (4.08 ± 2.78–1.68 ± 1.65 Pa), when compared with significantly increased SS value in the SB‐lateral subsegment 4.35 ± 5.04–16.50 ± 40.45 Pa). The explanation is that after stenting in the MV, the flow was redistributed immediately after percutaneous coronary intervention (PCI) and reversed back to its original 8 months later. However, the growth of the fibrous tissue causing in‐stent restenosis (ISR) is prohibited by sirolimus on the stent struts. In contrast, in a branch opened up by plain old balloon angioplasty (POBA), the flow did not change much, the flow could even be worse because it is shifted to the MV after the cross‐sectional area of the MV improved by stenting. However, thanks to POBA, there is increased fibrous tissue formation, enough to increase the SS and prevent further accumulation of cell and cholesterol needed for more restenosis. Conclusion: In the provisional approach, low endothelial SS correlated with no restenosis for patients who underwent stenting of the MV, while a contradictory combination of high SS and no restenosis was seen in the SB after only POBA. The mechanism of prevention of restenosis in the SB is by increasing the SS while in the MV, the mechanism of prevention of ISR is secondary to sirolimus on the stents struts. (J Interven Cardiol 2010;23:319–329)     

In‐Hospital and 12‐Month Postprocedural Clinical Outcome of Coronary Bifurcational Lesion Treatment with the Endeavor Stent

Background: The zotarolimus‐eluting stent (ZES) has been documented as significantly reducing restenosis and target lesion revascularization (TLR) requirement compared to bare metal stents (BMS). Methods: In this single‐centered, prospective study we sought to evaluate the short‐ and medium‐term outcomes of ZES placement in bifurcated coronary artery lesions. Between August 2006 and December 2007, 107 consecutive patients (110 bifurcations) were recruited to have ZES placement in the lesion. The provisional T stenting (PTS) technique was used in 96.3%. Angiographic success was 100% in main vessel (MV) cases and 97.2% in that of side branch (SB). Results: With a mean follow‐up of 12.4 ± 1.77 (mean ± SD) months there were four deaths, three from cardiac cause (2.85%). There were 18 patients (19 bifurcations) requiring TLR (17.59%) for clinical reasons. The only predictor of TLR was the use diameter of ZES ≤3 mm. Conclusion: ZES can be used for bifurcation lesions using the PTS technique with a high rate of intraprocedural success; however, frequency of TLR is high, especially for stents with a diameter ≤3 mm. (J Interven Cardiol 2010;23:188‐194)     

Preintervention angiographic and intravascular ultrasound predictors for side branch compromise after a single-stent crossover technique

A single stent crossover technique is the most common approach to treating bifurcation lesions. In 90 bifurcation lesions with side branch (SB) angiographic diameter stenosis <75%, we assessed preintervention intravascular ultrasound (IVUS; of main branch [MB] and SB) predictors for SB compromise (fractional flow reserve [FFR] <0.80) after a single stent crossover. Minimal lumen area (MLA) was measured within each of 4 segments (MB just distal to the carina, polygon of confluence, MB just proximal to polygon of confluence, and SB ostium). All lesions showed Thrombolysis In Myocardial Infarction grade 3 flow in the SB after MB stenting. Although angiographic diameter stenosis at the SB ostium increased from 26 ± 15% before the procedure to 36 ± 21% after stenting (p = 0.001), FFR <0.80 was observed in only 16 patients (18%). Negative remodeling (remodeling index <1) was seen in 83 (92%) lesions but did not correlate with FFR after stenting. Independent predictors for FFR after stenting were maximal balloon pressure (p = 0.002) and MLA of SB ostium before percutaneous coronary intervention (p <0.001), MLA within the MB just distal to the carina (p = 0.025), and plaque burden at the SB ostium before percutaneous coronary intervention (p = 0.005), but not angiographic poststenting diameter stenosis or minimal lumen diameter. For prediction of FFR <0.80 after percutaneous coronary intervention, the best cutoff of MLA within the SB ostium before percutaneous coronary intervention was 2.4 mm(2) (sensitivity 94%, specificity 69%). Also, the cutoff of plaque burden within the SB ostium before percutaneous coronary intervention was ≥51% (sensitivity 75%, specificity 71%). In 67 lesions with an MLA ≥2.4 mm(2) or plaque burden <50% before percutaneous coronary intervention, 63 (94%) showed FFR ≥0.80. However, FFR <0.80 was seen in only 12 (52%) of 23 lesions with an MLA <2.4 mm(2) and plaque burden ≥50%. In conclusion, there do not appear to be reliable IVUS predictors of functional SB compromise after crossover stenting.     

Ultrasound study of the prevalence of plaque at the carina in lesions that affect the coronary bifurcation. Implications for treatment with provisional stent

Introduction and objectives

The plaque distribution patterns in coronary bifurcation lesions are not well understood. It has been speculated that carina is free of plaque partly because of high wall shear stress providing an atheroprotective effect. To study plaque distribution with intravascular ultrasound (IVUS) in the coronary bifurcation and the prevalence of carina involvement.

Methods

IVUS study was performed on 195 coronary bifurcation lesions in the main vessel (MV) and on 91 in the side branch (SB). Plaque at the carina was considered when its thickness was > 0.3 mm. Plaque burden was measured at different levels: proximal reference, distal, carina and at the point of minimal lumen area (MLA).

Results

The prevalence of plaque at the carina was 32%. Its thickness was 0.8 (0.36) mm, less than that observed at the counter-carina [1.22 (0.54) mm; P < .01]. The prevalence was higher (52%) when the MLA point was distal to the carina. The plaque at the carina was associated with a lower incidence of damage at the SB ostium after stenting the MV (32% vs 54%; P < .04).

Conclusions

The carina is not immune to atherosclerosis, showing plaque at this level in one third of the bifurcations. The incidence of plaque is higher in those bifurcations with the MLA point distal to the carina and seems to be associated with a lower incidence of damage to the SB ostium.Full English text available from: www.revespcardiol.org     

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

Objective

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

Background

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

Methods

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

Results

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

Conclusion

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

     

血管内超声在冠状动脉分叉病变分型中应用的探讨

目的探讨血管内超声（IVUS）在冠状动脉分叉病变分型中的价值。方法经冠状动脉造影（CAG）确定的53例患者,共62处冠状动脉分叉病变,除常规CAG检查外,均行IVUS检查,根据主支（MV）和分支（SB）开口的斑块特点和分布进行病变类型的归纳与分类。结果分叉部位93.55%的MV斑块和98.39%的SB血管开口病变为偏心性斑块,斑块最大厚度呈相向存在或外侧壁分布的比例为77.42%。分叉部位共有6种主要病变类型：A型,MV偏心斑块位于SB开口对侧,SB开口的偏心斑块位于分叉脊对侧,占90.32%;B型,MV有向心斑块但未累及SB开口,SB开口的对侧主支上有斑块,占1.61%;C型,MV有向心性斑块并累及SB开口,SB开口的偏心斑块位于分支侧分叉脊的对侧,占1.61%;D型,MV有向心性斑块并累及SB开口及分叉脊的主支侧,占3.23%;E型,MV的偏心斑块位于SB开口对侧,SB血管开口有向心性病变,占1.61%;F型,MV的偏心斑块最大厚度位于SB侧,且斑块累及SB开口及分叉脊的主支侧,占1.61%。累及到分叉脊处的病变仅6.45%。结论冠状动脉分叉病变的IVUS分型不同于传统的CAG分型。病变的偏心性和外侧壁分布以及分叉脊的低病变率是IVUS分型的主要特点。     

Relative dependence of diameters of branches in coronary bifurcations after stent implantation in main vessel--importance of carina position

BACKGROUND AND AIM: Bifurcation lesions are relatively frequently encountered in everyday interventional practice. Stenting of the vessel chosen to be main (usually the larger one) frequently leads to stenosis at the ostium of the side branch (SB) and compromises its flow (side branch compromise--SBC). The relative dependence of main and side branch diameters, based on the concept of carina displacement of stent struts, was examined in a cohort of patients with bifurcation stenting. METHODS: We accept that the basic mechanism for SBC after stent placement in the parent vessel is carina shifting from expanded stent struts. The ostial SB minimal lumen diameter (MLD), percentage diameter stenosis (%DS) at maximal and calculated actual carina displacement, as well as distal limb diameter (DLD) in the main branch were calculated and compared with actually observed values. RESULTS: A group of 55 consecutive patients with acceptable quality angiograms formed the study population. General patient characteristics were similar to other bifurcation studies. Left anterior descending artery was predominantly treated in 73% of patients. There was worsening SB ostial stenosis after stent implantation (%DS increase from 48%+/-23% to 69%+/-21%, p <0.001) and final improvement because of kissing balloon inflation or SB postdilatation (post vs. final-69+/-21% and 53+/-25%, p<0.001). Stent implantation causes straightening of the main vessel, evident from a significant increase in angle C (pre- 148 degrees +/-19 degrees vs. 156 degrees +/-16 degrees after stenting, p=0.007). Relations between observed and predicted values for main branch DLD and %DS demonstrated a good correlation between predicted and observed values (for DLD r=0.66, p<0.001, and for %DS r=0.53, p <0.001). There was an excellent fit of regression lines between theoretical predictions and actual measurements for side branches (MLD r=0.91, p<0.001, %DS r=0.89, p<0.001).CONCLUSIONS: Carina displacement from stent struts is a major mechanism governing changes in coronary bifurcations after main vessel stenting. Improvement in the ostium of the side branch causes shifting back of the carina and a decrease of main vessel diameter. The long-term consequences of this phenomenon are not currently known.     

Long‐term outcome of provisional side‐branch T‐stenting for the treatment of unprotected distal left main coronary artery disease

Percutaneous coronary intervention (PCI) on distal left main (LM) remains an independent predictor of poor outcome. The strategy of implanting one stent on the main branch (MB), with provisional stenting on the side‐branch (SB) only when required (provisional T‐stenting), has become the default approach to most bifurcation lesions. This prospective registry sought to investigate the long‐term safety and efficacy of provisional SB T‐stenting for the treatment of unprotected distal LM disease in patients undergoing PCI. From January 2006 to May 2009, 107 consecutive patients affected by unprotected distal LM disease underwent PCI at our center with the intent to use a provisional SB‐stenting technique. We evaluated the rate of major adverse cardiac events (MACE) at long‐term follow‐up (up to 12–41 months). Procedural success was obtained in 98% of patients. A final kissing balloon inflation was performed in 95% and intravascular ultrasound in 83% of patients. Additional stenting on the SB after provisional stenting on MB was required in 29% of lesions. Long‐term follow‐up (3.5 years; 25–75th percentile and 1.1–4.5 years) was completed in 97% of patients. The cumulative incidence of MACE was 32.7%: all‐cause death was 15.8%, nonfatal myocardial infarction 8.4%, and target vessel revascularization 21.5%. At multivariable analysis, age (hazard ratio, 2.08; 95% confidence interval: 2.01–3.32, P = 0.03), European System for Cardiac Operative Risk Evaluation (HR 1.20, 95% CI: 1.04–1.33, P = 0.02), and diabetes mellitus (HR 3.48, 95% CI: 1.12–6.87, P = 0.01) were identified as independent predictors of MACE. In patients with unprotected distal LM disease undergoing PCI, a provisional strategy of stenting the MB only is associated with good long‐term clinical outcomes. © 2011 Wiley‐Liss, Inc.     

Immediate results of bifurcational stenting assessed with optical coherence tomography

Background : A tubular stent may adapt with difficulty to coronary bifurcation lesions (CBLs). Methods : Time domain or frequency domain (FD) optical coherence tomography (OCT) was performed to assess strut apposition immediately after stent implantation across four segments inside the bifurcation, in a consecutive series of patients. OCT pullbacks were performed in the main vessel (MV). Results : A total of 13,142 struts in 45 CBL in 41 patients were assessed. Strut malapposition was significantly more frequent in the half bifurcation facing the side‐branch (SB) ostium (42.9%) than in the proximal segment of the bifurcation 11.8%, half bifurcation opposite the SB 6.7%, or the distal segment 5.7% (all P < 0.0001). Lesions (n = 15) treated with stenting of both MV and SB had a total higher rate of malapposition than those (n = 30) treated with stenting of the MV only (17.6% vs. 9.5%; P = 0.0014). In latter group, lesions treated with FD‐OCT‐guided stent implantation (n = 13) presented a lower rate of malapposition than those treated with conventional angiographic‐guided stent implantation (n = 17) (7.1% vs. 17.5%; P = 0.005). Conclusions : In CBL, strut malapposition is particularly high at the SB ostium. However, a strategy of stenting MV only with adjunctive FD‐OCT guidance is associated with lower rates of malapposition. © 2012 Wiley Periodicals, Inc.     

Long-term outcome of simultaneous kissing stenting technique with sirolimus-eluting stent for large bifurcation coronary lesions.

OBJECTIVES: This study was conducted to evaluate the outcomes of simultaneous kissing stenting with sirolimus-eluting stent (SES). BACKGROUND: Percutaneous intervention for bifurcation coronary lesions is still challenging. METHODS: This study was designed to evaluate the long-term outcomes of 36 consecutive patients with large bifurcation coronary lesions who underwent simultaneous kissing stenting with SES. RESULTS: Lesion location was unprotected left main in 29 patients (81%) and anterior descending artery in 7 (19%). The patients received a combination of aspirin and clopidogrel for 6 months and cilostazol for 1 month. Mean proximal reference diameter was 4.05 +/- 0.68 mm. Compared with the side branch (SB), the main vessel (MV) involved longer lesions (25.8 +/- 17.0 mm vs. 10.2 +/- 10.8 mm, P < 0.001) and smaller preprocedural minimal lumen diameters (1.02 +/- 0.53 mm vs. 1.46 +/- 0.78 mm, P = 0.006) and was treated with larger stents (3.1 +/- 0.3 mm vs. 3.0 +/- 0.3 mm, P = 0.006). Angiographic success rate was 100%. Over the follow-up of 26.7 +/- 8.6 months, no deaths, myocardial infarctions or stent thromboses occurred. Target lesion revascularization was performed in five patients (14%). Overall angiographic restenosis occurred in 5/30 patients (17%), consisting of 4 (13%) at MV and 3 (10%) at SB. At follow-up angiography, a membranous diaphragm at the carina was identified in 14 patients (47%), but only one of whom was associated with angiographic restenosis. CONCLUSION: Simultaneous kissing stenting with SES appears a feasible stenting technique in large bifurcation coronary lesions. However, a new angiographic structure of carinal membrane developed in a half of patients at follow-up and its influence needs to be further investigated.     

Percutaneous coronary intervention for major bifurcation lesions using the simple approach: risk of myocardial infarction

Background Recent data has suggested that simple (main vessel only) stenting is the preferred approach for patients with bifurcation lesions. We sought to determine the feasibility and outcomes of this approach in a year long inclusive registry. Methods From August, 2004–2005, a registry of 1,600 consecutive patients undergoing PCI was reviewed. Patients undergoing PCI for major bifurcation lesions––≥70% stenosis in a major (≥2 mm) side branch and/or main vessel––were identified by review of the angiograms. Angiographic, clinical and treatment predictors of final SB compromise (≥70% stenosis and/or less than TIMI 3 final flow) were identified. Results Hundred and fifty eight patients who underwent initial stenting of the main vessel with subsequent rescue of the side branch if SB compromise occurred (“Provisional Main Vessel Stenting”) comprised the analysis population. Permanent SB compromise occurred in 16% of patients and was associated with an increased risk of large periprocedural MI and renal failure. Independent predictors of permanent SB compromise were lack of pre-PCI beta blockers, presence of diabetes mellitus, main vessel eccentric lesion and small SB vessel diameter. Conclusion Among unselected patients with major bifurcation lesions undergoing a “simple” stenting approach, there is a significant rate of large periprocedural infarction and side branch compromise.     

Clinical verification of a theory for predicting side branch stenosis after main vessel stenting in coronary bifurcation lesions

Objectives: To verify in a clinical scenario a theory for predicting side branch (SB) stenosis after main vessel stent implantation in coronary bifurcation lesions. Background: Many unresolved issues remain regarding SB compromise when the parent vessel is stented. Methods: Bifurcation lesions (all Medina types) were subjected to angiographic analysis to determine the angle, defined as α, between the axes of the parent vessel and the SB. Using the prediction that the percent diameter stenosis (%DS) is equal to the cosine of angle α and relating it to a formula to determine the minimal lumen diameter (MLD) led to the following equation: MLD = ds · (1 –cos α); ds refers to the diameter of the SB. The predicted and observed SB stenosis values following angiography were compared. Results: Fifty‐two patients with 57 lesions were included in the analysis. Patient demographics and characteristics were similar to those in previous studies. There was a high coefficient of determination between the predicted and observed values of %DS (r²= 0.82, P < 0.001) and MLD (r²= 0.86, P < 0.001). We determined a cutoff value of 70% for predicted %DS for SB closure. When using multivariate regression analysis, the only predictor of SB ostial stenosis after stenting was α angle, whereas the predictors of MLD included the angle α and the RVD of the SB. Conclusions: Our analysis shows that the most powerful independent predictor of SB compromise is a new variable angle α.     

Predictors and Periprocedural Myocardial Injury Rate of Small Side Branches Occlusion in Coronary Bifurcation Intervention

Occlusion of small side branch (SB) may result in significant adverse clinical events. We aim to characterize the predictors of small SB occlusion and incidence of periprocedural myocardial injury (PMI) in coronary bifurcation intervention.Nine hundred twenty-five consecutive patients with 949 bifurcation lesions (SB ≤ 2.0 mm) treated with percutaneous coronary intervention (PCI) were studied. All clinical characteristics, coronary angiography findings, PCI procedural factors, and quantitative coronary angiographic analysis data were collected. SB occlusion after main vessel (MV) stenting was defined as no blood flow or any thrombolysis in myocardial infarction (TIMI) flow grade decrease in SB after MV stenting. Multivariate logistic regression analysis was performed to identify independent predictors of small SB occlusion. Creatine kinase-myocardial band activity was determined by using an immunoinhibition assay and confirmed by mass spectrometry. Incidence of PMI between no SB occlusion group and SB occlusion group was compared.SB occlusion occurred in 86 (9.1%) of 949 bifurcation lesions. Of SB occlusion, total occlusion occurred in 64 (74.4%) lesions and a decrease in TIMI flow occurred in 22 (25.6%) lesions. True bifurcation lesion, irregular plaque, predilation in SB, preprocedural SB TIMI flow grade, preprocedural diameter stenosis of distal MV, preprocedural diameter stenosis of bifurcation core, bifurcation angle, diameter ratio between MV and SB, diameter stenosis of SB before MV stenting, and MV lesion length were independent risk factors of SB occlusion. We observed a significantly higher incidence of PMI in each cutoff level in patients with SB occlusion compared with those without SB occlusion.True bifurcation lesion, irregular plaque, and 8 other predictors were independent predictors of SB occlusion. Patients with small SB occlusion had significant higher incidence of PMI.     

A modified provisional stenting approach to coronary bifurcation lesions: clinical application of the "jailed-balloon technique"

Objectives: To demonstrate the application of a novel provisional side branch (SB) stenting strategy for coronary bifurcation lesions using a “jailed‐balloon” technique (JBT). Background: Adverse cardiac events are higher for percutaneous coronary intervention (PCI) of bifurcation lesions. Recent studies support the use of provisional SB stenting, but a risk of SB closure and a higher rate of target lesion revascularization (TLR) remain important limitations. Methods: From December 2007 to August 2010, 100 patients with 102 bifurcation lesions underwent PCI using the JBT. Baseline and postprocedural quantitative coronary angiography (QCA) analysis were performed. Procedural and immediate clinical outcomes were reviewed. Results: The majority of patients presented with acute coronary syndrome (68%) and had Medina class 1,1,1 bifurcation lesions (91%). TIMI 3 flow was established in 100% of main branch and 99% of SB lesions. QCA revealed preservation of the bifurcation angle after PCI (pre‐PCI: 59.6 ± 30.0; post‐PCI: 63.3 ± 26.8, P = 0.41). Nine patients (9%) had lesions that required rewiring and two patients (2%) required provisional stenting of the SB. SB loss occurred in one patient (1%). The jailed‐balloon or wire was not entrapped during any PCI. One patient (1%) suffered a periprocedural myocardial infarction (MI). Conclusions: Provisional stenting of complex coronary bifurcation lesions using a JBT is associated with a high procedural success rate, improved SB patency, and a low rate of immediate cardiac events. Further study is warranted to evaluate the role of JBT in improving long‐term clinical outcomes in PCI of complex bifurcation lesions. (J Interven Cardiol 2012;25:289–296)     

Drug-coated balloon in the treatment of coronary bifurcation lesions: A hope or hype?

When compared to non-bifurcation lesions, percutaneous coronary intervention in coronary bifurcation lesions is technically demanding and has historically been limited by lower procedural success rates and inferior clinical results. Following the development of drug-eluting stents, dramatically better results have been demonstrated. In most of the bifurcation lesions, the provisional technique of implanting a single stent in the main branch (MB) remains the default approach. However, some cases require more complex two-stent techniques which carry the risk of side branch (SB) restenosis. The concept of leaving no permanent implant behind is appealing because of the complexity of bifurcation anatomy with significant size mismatch between proximal and distal MB which may drive rates of in-stent restenosis and the potential impact of MB stenting affecting SB coronary flow dynamics. With the perspective of leaving lower metallic burden, a drug-coated balloon (DCB) has been utilized to treat bifurcations in both the MB and SB. The author gives an overview of the existing state of knowledge and prospects for the future for using DCB to treat bifurcation lesions.     

Proximal Side-Branch Optimization in Crush Stenting: A Step-by-Step Technical Approach in a Silicone Phantom Model

Provisional single drug-eluting stent (DES) strategy remains the standard of care in simple bifurcation lesions which comprise the vast majority of coronary bifurcations. Nevertheless, the presence of complex bifurcations which are defined based on the 1) Side Branch (SB) lesion length of >10 mm and 2) SB ostial diameter stenosis of >70% are approached with a 2-DES strategy upfront. The bifurcation angle will further define the most appropriate technique, with T-stenting more suitable in angulations close to 90°, Culotte and the family of Crush techniques more appropriate for acute angles of <75°. The Crush techniques which are composed of the classic Crush, mini-Crush and double kissing Crush (DK-Crush) share the core principle of protruding the SB DES within the Main Branch (MB) to minimize the risk of ostial SB restenosis, which remains the most prevalent etiology of stent failure during 2-stent approach in bifurcations. Proximal Side Optimization (PSO) is an additional technical consideration to further optimize the protruding SB struts enabling 1) optimal SB strut accommodation to the larger MB vessel diameter, 2) strut enlargement that will further facilitate effortless rewiring for kissing balloon inflation (KBI) avoiding unfavorable guide wire advancement in the peri-ostial SB area.     

Drug‐Eluting vs. Conventional Balloon for Side Branch Dilation in Coronary Bifurcations Treated by Provisional T Stenting

Objective

The origin of the side branch (SB) is the most common site for restenosis in coronary bifurcations. The end‐point is to compare the results of SB dilation with drug‐eluting balloon (DEB group) versus conventional balloon (BAL group) in bifurcations treated with provisional T stenting.

Methods and Results

Each group included 50 patients. In DEB, the origin of SB was dilated with a Sequent^® Please balloon. In both groups, a Taxus Liberté^® stent was implanted in the main vessel, with kissing balloon postdilation. If the outcome for the SB was suboptimal, a Taxus stent was implanted in BAL and a bare stent in DEB group. An angiographic follow‐up and IVUS were scheduled for 12 months later. Adverse events (MACE) were 24% in BAL versus 11% in DEB (P = 0.11), with greater revascularization (TLR) in the BAL group (22% vs. 12%, P = 0.16). At angiographic follow‐up, there was a lower percentage of SB restenosis in the DEB group (20% vs. 7%, P = 0.08), with less late loss (0.40 mm vs. 0.09 mm, P = 0.01).

Conclusion

Side branch dilation with a drug‐eluting balloon resulted in better angiographic outcomes than with a conventional balloon, with less late loss and restenosis at the 12‐month follow‐up. (J Interven Cardiol 2013;26:454‐462)