Provisional side branch-stenting for coronary bifurcation lesions: evidence of improving procedural and clinical outcomes with contemporary techniques

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.

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

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Proximal optimisation technique versus final kissing balloon inflation in coronary bifurcation lesions: the randomised, multicentre PROPOT trial

BACKGROUND

Clinical implications of the proximal optimisation technique (POT) for bifurcation lesions have not been investigated in a randomised controlled trial.

AIMS

This study aimed to investigate whether POT is superior in terms of stent apposition compared with the conventional kissing balloon technique (KBT) in real-life bifurcation lesions using optical coherence tomography (OCT).

METHODS

A total of 120 patients from 15 centres were randomised into two groups - POT followed by side branch dilation or KBT. Finally, 57 and 58 patients in the POT and KBT groups, respectively, were analysed. OCT was performed at baseline, immediately after wire recrossing to the side branch, and at the final procedure.

RESULTS

The primary endpoint was the rate of malapposed struts assessed by the final OCT. The rate of malapposed struts did not differ between the POT and KBT groups (in-stent proximal site: 10.4% vs 7.7%, p=0.33; bifurcation core: 1.4% vs 1.1%, p=0.67; core's distal edge: 6.2% vs 5.3%, p=0.59). More additional treatments were required among the POT group (40.4% vs 6.9%, p<0.01). At one-year follow-up, only one patient in each group underwent target lesion revascularisation (2.0% vs 1.9%).

CONCLUSIONS

POT followed by side branch dilation did not show any advantages over conventional KBT in terms of stent apposition; however, excellent midterm clinical outcomes were observed in both strategies.

Provisional stenting or not provisional stenting: seven critical points for bifurcations treatment with a glimpse on left main bifurcation stenting

Stenting of coronary bifurcation lesions represents a challenge for the interventional cardiologist. A bifurcation lesion could be treated with several techniques. Therefore, it is of paramount importance to decide the strategical approach at the beginning of the procedure evaluating the patient's bifurcation anatomy, the angle between main and side branch, plaque burden at the level of the carina, and size of the side branch. Although it is clear that all bifurcation's treatment techniques have each one their advantages and disadvantages, provisional stenting remains the gold-standard technique, because it leaves the possibility to switch to other technical solutions with optimal angiographic and long-term clinical results. In this review, different tips and tricks for left main and bifurcation stenting are debated.

Summary of Practice Considerations for Percutaneous Coronary Intervention of Left Main Bifurcation Disease

Left main bifurcation percutaneous coronary intervention is a challenging subset that requires expertise in techniques that are in constant modification. Imaging is important in lesion preparation and optimising outcomes. The interventionalist needs to be highly skilled in the different techniques, as missteps may lead to stent thrombosis and critical in-stent restenosis. Lesion classification between simple and complex identifies those who would best benefit from a two-stent technique. Current technical approaches and practice considerations are summarised in this manuscript.

The Proximal Optimization Technique Improves Clinical Outcomes When Treated without Kissing Ballooning in Patients with a Bifurcation Lesion

Background and Objectives

There are limited data regarding the clinical efficacy of the proximal optimization technique (POT) in the treatment of coronary bifurcation lesions. We investigated the influence of POT on the clinical outcomes of patients with coronary bifurcation lesions.

Methods

We enrolled a total of 1,191 patients with a bifurcation lesion with a side branch (SB) diameter ≥2.5 mm treated with a drug-eluting stent from 18 centers between January 2003 and December 2009. The primary outcome was major adverse cardiac events (MACEs: cardiac death, myocardial infarction or target lesion revascularization [TLR]). We performed one-to-many (1:N) propensity score matching with non-fixed matching ratio.

Results

POT was performed in 252 patients. During follow-up (median 37 months), the incidence of MACE was lower in the POT group than it was in the non-POT group (adjusted hazard ratio, 0.43; 95% confidence interval [CI], 0.24–0.79; p=0.006). After propensity score matching, these were 0.34; 95% CI, 0.17–0.69; p=0.003 for MACE and 0.37; 95% CI, 0.17–0.78; p=0.01 for TLR. The use of POT was associated with significantly lower TLR in patients treated without kissing ballooning, but was not in those who underwent kissing ballooning (p for interaction=0.03).

Conclusions

In coronary bifurcation lesions with a large SB, POT may be beneficial to improve long-term clinical outcome, particularly in patients treated without kissing ballooning during the procedure.

Trial Registration

ClinicalTrials.gov Identifier: NCT01642992

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

AIM

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

METHODS AND RESULTS

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

CONCLUSION

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

Understanding the Coronary Bifurcation Stenting

Coronary bifurcation stenting is still complex and associated with a high risk of stent thrombosis and restenosis even with contemporary techniques. Although provisional approach has been proved to be the standard strategy of treatment, There is still lack of evidences for multiple steps of the procedure. For so many years we have been focused on the optimization of side branch (SB), but the clinical outcome is mostly dependent on the main vessel (MV) stenting. The optimal expansion of MV stent without the compromise of SB is the ultimate goal to achieve in the coronary bifurcation stenting. Understanding the anatomy and physiology of coronary bifurcation lesion should be the most important step to this goal. The relationship of vessel diameter between branches and the anatomical and functional significance of plaque shift and carina shift are two most important concepts to understand. They are the science behind the predictors of SB occlusion, and the rationale of proximal optimization technique and final kissing ballooning. This specific review will be devoted to review those concepts as well as clinical evidences to support them.

Clinical Outcome of Double Kissing Crush Versus Provisional Stenting of Coronary Artery Bifurcation Lesions: The 5-Year Follow-Up Results From a Randomized and Multicenter DKCRUSH-II Study (Randomized Study on Double Kissing Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions)

BACKGROUND

Provisional stenting is effective for anatomic simple bifurcation lesions. Double kissing crush stenting reduces the 1-year rate of target lesion revascularization. This study aimed to investigate the 5-year clinical results of the DKCRUSH-II study (Randomized Study on Double Kissing Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions).

METHODS AND RESULTS

A total of 370 patients with coronary bifurcation lesions who were randomly assigned to either the double kissing crush or provisional stenting group in the DKCRUSH-II study were followed for 5 years. The primary end point was the occurrence of a major adverse cardiac event at 5 years. Patients were classified by simple and complex bifurcation lesions according to the DEFINITION criteria (Definitions and Impact of Complex Bifurcation Lesions on Clinical Outcomes After Percutaneous Coronary Intervention Using Drug-Eluting Stents). At 5 years, the major adverse cardiac event rate (23.8%) in the provisional stenting group was insignificantly different to that of the double kissing group (15.7%; P=0.051). However, the difference in the target lesion revascularization rate between 2 groups was sustained through the 5-year follow-up (16.2% versus 8.6%; P=0.027). The definite and probable stent thrombosis rate was 2.7% in each group (P=1.0). Complex bifurcation was associated with a higher rate of target lesion revascularization (21.6%) at 5 years compared with 11.1% in patients with a simple bifurcation (P=0.037), with an extremely high rate in the provisional stenting group (36.8% versus 12.5%, P=0.005) mainly because of final kissing balloon inflation (19.4% versus 5.2%; P=0.036).

CONCLUSIONS

The double kissing crush stenting technique for coronary bifurcation lesions is associated with a lower rate of target lesion revascularization. The optimal stenting approach based on the lesions' complexity may improve the revascularization for patients with complex bifurcations.

CLINICAL TRIAL REGISTRATION

URL: http://www.chictr.org. Unique identifier: ChiCTR-TRC-0000015.