Long-term clinical results and predictors of adverse outcomes after drug-eluting stent implantation for bifurcation lesions in a real-world practice: the COBIS (Coronary Bifurcation Stenting) registry

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 technique of proximal optimization with kissing balloon inflation in bifurcation lesions

BACKGROUND

Percutaneous coronary interventions (PCI) of bifurcation lesions poses a technical challenge with a high complication rate. Kissing balloon inflation (KBI) and proximal optimization technique (POT) are used to correct bifurcation carina after stenting. However, both may still lead to uncomplete strut apposition to the side branch (SB) lateral wall. Proposed herein, is a new stent-optimization technique following bifurcation stenting consisting of a combination of POT and KBI called proximal optimization with kissing balloon inflation (POKI).

METHODS

Bench and in-vivo evaluations were performed. For the bench visualization bifurcated silicone mock vessel was used. The POKI technique was simulated using a 3.5 mm POT balloon. For the in-vivo evaluation patients with angiographic bifurcation lesions in a native coronary artery with diameter ≥ 2.5 mm and ≤ 4.5 mm, SB diameter ≥ 2.0 mm, and percentage diameter stenosis (%DS) more than 50% in the main vessel (MV) were included. Provisional stenting was the default strategy.

RESULTS

In total 41 vessels were evaluated. The target vessel was left main in 9 (22.0%) patients, left anterior descending artery - in 26 (63.4%), left circumflex artery - in 4 (9.8%) and right coronary artery - in 2 (4.9%). The predominant type of bifurcation was Medina 1-1-1 (61.8%). Baseline proximal MV DS% was 60.0 ± 23.7%, distal MV DS% - 58.8 ± 28.9% and SB DS% 53.0 ± 32.0%. The application of POKI was feasible in 41 (100%) of the vessels. Post-PCI residual DS at proximal MV was 11.5 ± 15.4%, distal MV - 6.6 ± 9.3%, and SB - 22.9 ± 28.5%. Both procedural and angiographic success was 100%.

CONCLUSIONS

POKI is a novel stent-optimization technique for bifurcation lesions. It showed excellent feasibility and success rate both in bench and in-vivo evaluation.

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

BACKGROUND

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

Background

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

Objectives

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

Methods

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

Results

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

Conclusions

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

Optimal strategy for side branch treatment in patients with left main coronary bifurcation lesions

INTRODUCTION AND OBJECTIVES

There are no guidelines regarding the most appropriate approach for provisional side branch (SB) intervention in left main (LM) bifurcation lesions.

METHODS

The present prospective, randomized, open-label, multicenter trial compared conservative vs aggressive strategies for provisional SB intervention during LM bifurcation treatment. Although the trial was designed to enroll 700 patients, it was prematurely terminated due to slow enrollment. For 160 non-true bifurcation lesions, a 1-stent technique without kissing balloon inflation was applied in the conservative strategy, whereas a 1-stent technique with mandatory kissing balloon inflation was applied in the aggressive strategy. For 46 true bifurcation lesions, a stepwise approach was applied in the conservative strategy (after main vessel stenting, SB ballooning when residual stenosis> 75%; then, SB stenting if residual stenosis> 50% or there was a dissection). An elective 2-stent technique was applied in the aggressive strategy. The primary outcome was a 1-year target lesion failure (TLF) composite of cardiac death, myocardial infarction, or target lesion revascularization.

RESULTS

Among non-true bifurcation lesions, the conservative strategy group used a smaller amount of contrast dye than the aggressive strategy group. There were no significant differences in 1-year TLF between the 2 strategies among non-true bifurcation lesions (6.5% vs 4.9%; HR, 1.31; 95%CI, 0.35-4.88; P=.687) and true bifurcation lesions (17.6% vs 21.7%; HR, 0.76; 95%CI, 0.20-2.83; P=.683).

CONCLUSIONS

In patients with a LM bifurcation lesion, conservative and aggressive strategies for a provisional SB approach have similar 1-year TLF rates.

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

OBJECTIVES

The aim of the current study was to evaluate the long-term clinical impact of fractional flow reserve (FFR) in jailed left circumflex coronary artery (LCx) after left main coronary artery (LM) simple crossover stenting.

BACKGROUND

Although the provisional side-branch intervention with FFR guidance has been validated for non-LM bifurcation lesions, the outcome of such a strategy in LM bifurcation disease is not well-known.

METHODS

Patients who underwent LM-to-left anterior descending coronary artery simple crossover stenting and who had FFR measurements in the LCx thereafter were enrolled. A low FFR was defined as ≤0.80. The clinical outcomes were assessed by the 5-year rate of target lesion failure (TLF) (a composite of cardiac death, target-vessel myocardial infarction, or target lesion revascularization).

RESULTS

In 83 patients, the mean FFR of the LCx after LM stenting was 0.87 ± 0.08, and 14 patients (16.9%) had a low FFR. There was no correlation between the FFR and angiographic % diameter stenosis in jailed LCx (R² = 0.039; p = 0.071) and there was no difference in the angiographic % diameter stenosis in the high and low FFR groups. At 5 years, the low FFR group had a significantly higher rate of TLF than the high FFR group (33.4% vs. 10.7%; hazard ratio: 4.09, 95% confidence interval: 1.15 to 14.52; p = 0.029). However, there was no difference in the clinical outcomes according to the angiographic % diameter stenosis. In a multivariate analysis, a low FFR was an independent predictor of the risk for a 5-year TLF (hazard ratio: 6.49; 95% confidence interval: 1.37 to 30.73; p = 0.018).

CONCLUSIONS

The patients with a high FFR in jailed LCx had better 5-year outcomes than those with a low FFR. The FFR measurement in jailed LCx can be helpful in selecting an adequate treatment strategy and may reduce unnecessary complex procedures.

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.

Transfer of Low-Density Lipoproteins in Coronary Artery Bifurcation Lesions with Stenosed Side Branch: Numerical Study

Evidence from clinical data suggests that the stenotic side branch (SB) is one of the key predictors for SB occlusion-based adverse events. In this study, we hypothesized that coronary bifurcations with stenotic SB might lead to severe concentration polarization of atherogenic lipids, such as the low-density lipoproteins (LDL), motivating the adverse events in the clinic. To confirm this hypothesis, this work numerically investigated the transport of LDL in different bifurcation lesions based on the Medina classification with various location and stenosis severities. The results showed that the coronary bifurcations with stenotic SB might be suffering more serious concentration polarization of LDL on the luminal surface of the SB due to higher level of LDL concentrations. Moreover, compared to the other bifurcation lesion types, the type (1,0,1) had the highest luminal surface LDL concentration along the SB and the highest degree of risk to enhance the process of atherosclerosis. In addition, this study also showed that the luminal surface LDL concentration increased with elevated stenosis severity. The type (1,0,1) with the severe stenosis (75% diameter reduction) had the highest concentration at the SB. In conclusion, these results suggested that both location of lesions and stenosis severities had great influence on the distribution of LDL on the luminal surface of the SB. Therefore, the estimation of disease severity and the interventional therapy should be carried out not only according to the stenosis severities in clinic. Moreover, compared to the other bifurcation lesion types, the type (1,0,1), rather than the type (1,1,1) as usually considered, had the highest luminal surface LDL concentration along the SB and the highest degree of risk to enhance the process of atherosclerosis.

Application of the MADS classification system in a "mega mammoth" stent trial: Feasibility and preliminary clinical implications

OBJECTIVES AND BACKGROUND

We attempted to test the feasibility of application of the MADS classification system in the largest stent trial to date and evaluate the preliminary clinical implications of this approach.

METHODS

In the randomized GLOBAL LEADERS trial, testing two different antiplatelet strategies in patients undergoing PCI with bivalirudin and biolimus-eluting stents, the e-CRF was dedicated to bifurcation treatment according to the MADS classification. Based on this e-CRF, the techniques used for bifurcations treatment in GLOBAL LEADERS were described and compared with two large, all-comer registries of bifurcations treatment (I-BIGIS and COBIS), used as historical controls.

RESULTS

Among 15,991 patients enrolled in the trial, 22,921 lesions treated at the index and staged procedure were available for analysis and 2,757 of these lesions were bifurcations and 7 were trifurcation lesions. The e-CRF-based MADS classification was achieved in 2,757 of these lesions (100%). 80.3% of bifurcations were treated using a single stent, 18.9% using 2 stents and 0.7% using 3 stents. Overall, the "main across side first" approach (A) was used in 77.4% with the "side branch first" approach (S) being the second most frequently used technique (10.2%). A single stent was used in the majority of the "A" approach (87.9%). A reduction in the use of 2-stent techniques (from 33.9 to 18.9%) was observed between GLOBAL LEADERS and I-BIGIS. The "A" approach was the most frequently used technique in GLOBAL LEADERS, while in COBIS the "S" strategy was most frequently employed.

CONCLUSIONS

Application of the MADS classification through an e-CRF was feasible in the largest stent trial today and provided useful information about the trends observed overtime 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.

Differential effect of side branch intervention on long-term clinical outcomes according to side branch stenosis after main vessel stenting: Results from the COBIS (Coronary Bifurcation Stenting) Registry II

BACKGROUND

Indication of side branch (SB) intervention after main vessel (MV) stenting is not established for coronary bifurcation lesions.

METHODS

We evaluated 2017 patients who were treated with 1-stent technique or MV stenting as a first strategy. Patients undergoing SB intervention after MV stenting (SB intervention group, n=929) were compared to those treated with MV stenting only (no-SB intervention group, n=1088).

RESULTS

During a median follow-up of 37months, cardiac death or myocardial infarction (MI) tended to occur less frequently in the SB intervention group than in the no-SB intervention group (1.8% versus 2.9%; adjusted hazard ratio [HR] 0.53; 95% confidence interval [CI] 0.25-1.11; P=0.09). There was a significant interaction between SB intervention and SB stenosis after MV stenting (P for interaction <0.01). Among 1077 patients with diameter stenosis of SB ≥50% after MV stenting, SB intervention was associated with a lower risk of cardiac death or MI (1.2% versus 4.2%; adjusted HR 0.22; 95% CI 0.09-0.52; P<0.01). However, among 940 patients with diameter stenosis of SB <50%, there was no significant difference in cardiac death or MI between the SB intervention group and the no-SB intervention group (3.5% versus 2.2%; adjusted HR 1.36; 95% CI 0.58-3.20; P=0.48).

CONCLUSIONS

The effect of SB intervention differed according to SB stenosis after MV stenting. SB intervention may reduce cardiac death or MI in bifurcation lesions with diameter stenosis of SB ≥50% after MV stenting.

Long-Term Clinical Outcomes of True and Non-True Bifurcation Lesions According to Medina Classification- Results From the COBIS (COronary BIfurcation Stent) II Registry

BACKGROUND

Little is known about the clinical outcomes of patients with different types of coronary bifurcation lesions. We sought to compare long-term clinical outcomes of patients with true or non-true bifurcation lesions who underwent percutaneous coronary intervention.

METHODS AND RESULTS

We compared major adverse cardiac events (MACE: cardiac death, myocardial infarction [MI], or target lesion revascularization) between 1,502 patients with true bifurcation lesions (51.8%) and 1,395 with non-true bifurcation lesions (48.2%). True bifurcation lesions were defined as Medina classification (1.1.1), (1.0.1), or (0.1.1) lesions. During a median follow-up of 36 months, MACE occurred in 296 (10.2%) patients. Patients with true bifurcation lesions had a significantly higher risk of MACE than those with non-true bifurcation lesions (HR 1.39; 95% CI 1.08-1.80; P=0.01). Among true bifurcation lesions, Medina (1.1.1) and (0.1.1) were associated with a higher risk of cardiac death or MI than Medina (1.0.1) (HR 4.15; 95% CI 1.01-17.1; P=0.05). During the procedure, side branch occlusion occurred more frequently in Medina (1.1.1) and (1.0.1) than Medina (0.1.1) lesions (11.5% vs. 7.4%, P=0.03).

CONCLUSIONS

Patients with true bifurcation lesions had worse clinical outcomes than those with non-true bifurcation lesions. Procedural and long-term clinical outcomes differed according to the type of bifurcation lesion. These findings should be considered in future bifurcation studies.

The impact of side branch predilatation on procedural and long-term clinical outcomes in coronary bifurcation lesions treated by the provisional approach

INTRODUCTION AND OBJECTIVES

It is uncertain whether side branch predilatation before main vessel stenting is necessary. We evaluated the effect of side branch predilatation on outcomes in percutaneous coronary intervention for true nonleft main bifurcation determined by the Medina classification using the provisional approach.

METHODS

Target vessel failures (composite of cardiac death, myocardial infarction, or target vessel revascularization) were compared between patients who underwent side branch predilatation (predilatation group, n = 175) and those who did not (nonpredilatation group, n = 662).

RESULTS

Final kissing-balloon inflation (57.1% vs 35.8%; P < .001) was performed more frequently and the cross-over rate to a 2-stent technique (14.9% vs 5.1%; P < .001) was higher in the predilatation group. During a median follow-up of 21 months, the predilatation group had a higher incidence of target vessel failures (14.3% vs 6.8%; P = .002) and target vessel revascularization (12.0% vs 5.6%; P = .003), but not of cardiac death or myocardial infarction compared with the nonpredilatation group. On multivariate analysis, side branch predilatation was associated with a higher occurrence of target vessel failures (adjusted hazard ratio = 2.11; 95% confidence interval, 1.27-3.50; P = .004). These results remained consistent after a propensity score-matched population analysis (for target vessel failures, adjusted hazard ratio = 2.63; 95% confidence interval, 1.09-6.34; P = .0031) and they were also constant among the various subgroups, according to the bifurcation angle, calcification, and diameter stenosis of the side branch.

CONCLUSIONS

Side branch predilatation before main vessel stenting may be associated with an increased risk of repeat revascularization in patients with true nonleft main bifurcation treated by the provisional approach.

TRIAL REGISTRATION

ClinicalTrials.gov number: NCT00851526.

Long-term outcomes of simple crossover stenting from the left main to the left anterior descending coronary artery

BACKGROUND/AIMS

Although complex bifurcation stenting in patients with non-left main (LM) bifurcation lesions has not yielded better clinical outcomes than simpler procedures, the utility of complex bifurcation stenting to treat LM bifurcation lesions has not yet been adequately explored.

METHODS

In the present study, patients who underwent LM-to-left anterior descending (LAD) coronary artery simple crossover stenting to treat significant de novo distal LM or ostial LAD disease, in the absence of angiographically significant ostial left circumflex (LCX) coronary artery disease, were consecutively enrolled. The frequencies of 3-year major adverse cardiovascular events (MACEs; cardiac death, myocardial infarction, and target lesion revascularization), were analyzed.

RESULTS

Of 105 eligible consecutive patients, only 12 (11.4%) required additional procedures to treat ostial LCX disease after main vessel stenting. The mean percentage diameter of ostial LCX stenosis increased from 22.5% ± 15.2% to 32.3% ± 16.3% (p < 0.001) after LM-to-LAD simple crossover stenting. The 3-year incidence of MACEs was 9.7% (cardiac death 2.2%; myocardial infarction 2.2%; target lesion revascularization 8.6%), and that of stent thrombosis 1.1%. Of seven cases (7.5%) requiring restenosis, pure ostial LCX-related repeat revascularization was required by only two.

CONCLUSIONS

Simple crossover LM-to-LAD stenting without opening of a strut on the LCX ostium was associated with acceptable long-term clinical outcomes.

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

OBJECTIVES

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Impact of acute coronary syndrome classification and procedural technique on clinical outcomes in patients with coronary bifurcation lesions treated with drug-eluting stents

BACKGROUND

We examined the impact of non-ST-segment elevation acute coronary syndrome (NSTE-ACS) on clinical outcomes in patients with bifurcation lesions treated with drug-eluting stents.

HYPOTHESIS

We hypothesized that NSTE-ACS would be attributable to the increased risk of major adverse cardiac events (MACE) in bifurcation percutaneous coronary intervention.

METHODS

We enrolled 1668 patients, using data from a multicenter real-world bifurcation registry. The primary objective was to compare the 2-year cumulative risk of MACE in patients with NSTE-ACS to those with stable angina. Major adverse cardiac events were defined as the composite endpoint of cardiac death, myocardial infarction (MI), and target-lesion revascularization.

RESULTS

Non-ST-segment elevation acute coronary syndrome was seen in 969 (58.1%) patients and stable angina in 699. Major adverse cardiac events occurred in 7.3% of NSTE-ACS patients and in 5.2% with stable angina (P = 0.042). However, cardiac death, MI, and target-lesion revascularization were similar between the 2 groups. We stratified patients with NSTE-ACS into those with non-ST-segment elevation MI and those with unstable angina. Cumulative risks of 2-year MACEs were 7.0% in non-ST-segment elevation MI patients and 7.5% in unstable angina patients (P = 0.87). In the NSTE-ACS cohort, the baseline lesion length in the side branch (adjusted hazard ratio [HR]: 1.04, 95% confidence interval [CI]: 1.01-1.07, P = 0.022), paclitaxel-eluting stents in the main vessel (adjusted HR: 2.02, 95% CI: 1.21-3.40, P = 0.008), and final kissing ballooning (adjusted HR: 1.88, 95% CI: 1.10-3.21, P = 0.021) were independent predictors of MACE.

CONCLUSIONS

Compared with stable angina patients, the NSTE-ACS patients who underwent bifurcation percutaneous coronary intervention had an increased risk of MACE during the 2-year follow-up.

A randomized comparison of sirolimus- vs. paclitaxel-eluting stents for treatment of bifurcation lesions by single stent and kissing balloon: results of the SINGLE KISS trial

BACKGROUND

In the treatment of bifurcation lesions, routine stenting of both branches has thus far failed to demonstrate a clear clinical advantage over a provisional one-stent strategy. On the other hand, large scale data evaluating different stent types for clinical outcomes after one-stent treatment with final kissing inflation (FKI) of bifurcation lesions is also limited. This prospective study evaluated the clinical and angiographic outcomes of paclitaxel-eluting stents (PES) vs. sirolimus-eluting stents (SES) in single crossover main branch stenting followed by FKI in patients with bifurcation lesions.

METHODS

We randomized 800 patients with single bifurcation lesions to PES (n=400) and SES (n=400) groups.

RESULTS

Crossover rates to the two-stent strategy were low in both groups (PES 1.5%, SES 2.8%; p=0.23). At 1 year, there was no significant difference in the primary endpoint of this study, target lesion revascularization rate (PES 3.8%, SES 3.2%, hazard ratio 0.83; 95% confidence interval 0.39 to 1.76; p=0.62). Stent thrombosis occurred in only 1 case in the SES group after 282 days. At 9 months, a total of 593 patients underwent quantitative coronary measurement. The main branch restenosis rate in the PES group was significantly higher than that of the SES group (PES 12.2%, SES 5.5%; p=0.004), however both groups exhibited similar high side branch restenosis rates (PES 17.2%, SES 19.3%; p=0.6).

CONCLUSIONS

In patients with bifurcation lesions, a single stent strategy using PES and SES with FKI indicated similar 1 year clinical outcomes and safety profiles.

Coronary bifurcation lesions treated with simple approach (from the Cordoba & Las Palmas [CORPAL] Kiss Trial)

The present report compared the incidence of 1-year clinical events in patients with bifurcation lesions that had been treated with a simple approach who were randomized to either a simultaneous final kissing balloon (KB) or an isolated side-branch (SB) balloon post-dilation. From February 2007 to December 2008, 293 patients with all types of Medina bifurcation lesions were enrolled in a prospective study. All patients underwent implantation of a sirolimus- or everolimus-eluting stent across the bifurcation and provisional SB stenting. Patients with no SB ostial compromise or those needing a second stent were excluded from the present study (n = 49). The eligible patients were randomly assigned to treatment with final KB inflation (n = 124, KB group) or isolated balloon after dilation (n = 120, non-KB group). No significant differences were found between the patients from the KB and non-KB groups in terms of age, risk factors, clinical status, or location of the bifurcation lesions. The angiographic data and immediate results were also similar in both groups. Four patients experienced a non-Q-wave acute myocardial infarction in the hospital: three (2%) from the KB group and one (1%) from the non-KB group. Two in-hospital deaths occurred in the non-KB group. Target lesion revascularization was required in 7 patients (3%): 5 from the KB group and 2 from the non-KB group. Late mortality occurred in 3 patients from the KB group and 2 patients from the non-KB group. The incidence of major events at 1 year (death, target lesion revascularization, or acute myocardial infarction) was similar in both groups: 11 (9%) from the KB group and 7 (6%) from the non-KB group (p = NS). In conclusion, no differences in the clinical outcome at 1 year of follow-up were observed between the patients with bifurcation lesions treated with a simple approach and either a simultaneous final KB or an isolated SB balloon post-dilation.

Evaluation of local flow conditions in jailed side branch lesions using computational fluid dynamics

Background and Objectives

Lesions of vascular bifurcation and their treatment outcomes have been evaluated by anatomical and physiological methods, such as intravascular ultrasound and fractional flow reserve (FFR). However, local changes in flow dynamics in lesions of bifurcation have not been well evaluated. This study aimed at evaluating changes in the local flow patterns of bifurcation lesions.

Materials and Methods

Eight (n=8) representative simulation-models were constructed: 1 normal bifurcation, 5 main-branch (MB) stenting models with various side-branch (SB) stenoses (ostial or non-ostial 75% diameter stenosis with 1- or 2-cm lesion lengths, ostial 75% diameter stenosis caused by carina shift), and 2 post-kissing models (no or 50% SB residual stenosis). Pressure, velocity, and wall shear stress (WSS) profiles around the bifurcation sites were investigated using computational fluid dynamics.

Results

Post-stenting models revealed significant pressure drop in the SB (FFR<0.75), excluding the carina shift model (FFR=0.89). In the post-kissing models, there was no significant pressure drop. All post-stenting models revealed eccentric low velocity flow patterns and areas of low WSS, primarily in the lateral wall on distal MB. Post-kissing angioplasty improved pressure drop in the SB but resulted in alteration of flow distribution in the MB. In the carina shift model, kissing ballooning resulted in deteriorated local flow conditions due to increased area of low velocity and WSS.

Conclusion

This study suggests that the most commonly used bifurcation intervention strategy may cause local flow disturbances, which may partially explain high restenosis and event rates in patients with bifurcation lesions.