Clinical outcomes following bifurcation double-stenting with bioresorbable scaffolds

Impact of directional coronary atherectomy followed by drug-coated balloon strategy to avoid the complex stenting for bifurcation lesions

Although the simple single stenting rather than complex double stenting is recommended on percutaneous coronary intervention (PCI) for bifurcation lesions, double stenting cannot always be avoided. We investigated the impact of directional coronary atherectomy (DCA), followed by drug-coated balloon (DCB) treatment to reduce the number of stents and avoid complex stenting in PCI for bifurcation lesions and short-term patency. DCA treatment without stents was attempted for 27 bifurcation lesions in 25 patients, of those, 26 bifurcation lesions in 24 patients were successfully treated and 3-month follow-up angiography and optical coherence tomography (OCT) were performed. Sixteen lesions (59.3%) were related to left main trunk distal bifurcations, and 7 (25.9%) were true bifurcation lesions. Among the true bifurcation lesions, 4 lesions (57.1%) needed 1 stent, and the other 3 lesions (42.9%) needed no stents. Among the non-true bifurcation lesions, 1 lesion (5.0%) needed bailout stent and other lesions (95.0%) needed no stents. According to DCA followed by DCB treatment, the angiographic mean diameter stenosis improved from 65.5 ± 15.0% to 7.8 ± 9.8%, and the mean plaque area in intravascular ultrasound improved from 80.4 ± 10.5% to 39.0 ± 11.5%, respectively. Angiographic and OCT late lumen loss values were 0.2 ± 0.6 mm and 1.4 ± 1.9 mm, respectively. No patient had in-hospital major adverse cardiac events (MACE) and 3-month MACE. In conclusion, compared with standard provisional side branch stenting strategy, DCA followed by DCB treatment might reduce the number of stents, avoid complex stenting for major bifurcation lesions and provide good short-term outcomes.

Safety and Efficacy of Bioresorbable Vascular Scaffolds in Coronary Bifurcation Lesions: A Systematic Review and Meta-Analysis

INTRODUCTION

Coronary bifurcation lesions (CBL) are one fifth of all coronary lesions and they do not have an optimal strategy for stenting yet. Bioresorbable scaffolds (BRS) are novel inventions proposed to be the optimal solution. The aim of this systematic review was to assess the role of BRS in treating CBL by comparing it to dedicated bifurcation stents (DBS).

METHODS

A systematic review was conducted following the PRISMA guidelines, searching databases such as ScienceDirect, EMBASE, MEDLINE, NIH, TRIP, PUBMED, and ClinicalTrials. gov. The risk of bias was assessed by MINORS and modified Cowley's criteria. Q statistic was used for heterogeneity testing and a meta-analysis was conducted using the "meta" package in the R software application.

RESULTS

Fourteen studies were included with an average follow-up period of twelve months. Almost 80% of the participants were male (p-value= 0.148) and around two-thirds were smokers. Meta-analysis was performed for myocardial infarction (MI), target lesion revascularisation (TLR), major adverse cardiac events (MACE), and stent thrombosis (ST). These showed statistically nonsignificant differences, with a slight trend favouring BRS except with stent thrombosis.

CONCLUSION

There is a lack of randomised trials on the topic, which may be an area for further research. But the results showed favourable yet statistically insignificant outcomes for BRS except for ST, an issue that can be addressed with technological advancement.

Angiographic and Midterm Outcomes of Bioresorbable Vascular Scaffold for Coronary Bifurcation Lesions

Data on the angiographic and clinical performance of bioresorbable vascular scaffolds (BVS) for bifurcation lesions treatment are still limited. Data were examined of 107 patients with at least 1 coronary bifurcation lesion involving a side branch ≥2mm. Angiographic and clinical outcomes were collected. Optical coherence tomography analysis was performed in a subgroup of patients. Between July 2009 and December 2015, 423 patients underwent PCI with Absorb BVS. A total of 110 lesions were identified as bifurcations, of which 24.5% were classified as true bifurcation lesions. Lesion complexity B2/C was 68.1%. Ninety-five out of 110 lesions were treated by provisional stenting technique while 2 stenting strategy was the final approach in 15 lesions. Procedural success of main branch was 100% whereas side-branch impairment at the end of the procedure was 4.5%. The mean follow-up was 21 months with one-third of the patients followed up for at least 2 years. The overall target lesion failure and scaffold/stent thrombosis rate at 1 year was 7.8% and 3.9%, respectively. In conclusion the results of the present analysis suggest the BVS implanted in bifurcations lesions are associated with procedural safety and angiographic success as well as acceptable target lesion failure rate at 1 year.

Hybrid Percutaneous Coronary Intervention With Bioresorbable Vascular Scaffolds in Combination With Drug-Eluting Stents or Drug-Coated Balloons for Complex Coronary Lesions

Bioresorbable vascular scaffolds (BVS) have become an attractive option in the percutaneous coronary intervention field due to the potential advantages associated with the complete resorption process that occurs within a few years. However, current-generation BVS have several limitations including thicker struts, reduced radial strength, and limited expansion capability when compared with drug-eluting stents (DES). As a result, complex coronary disease often contains BVS-inappropriate/unfavorable segments. This does not necessarily mean that BVS use must be completely avoided, and minimizing the length of permanent metallic caging may still be advantageous. Operators should fully understand the limitations of current BVS, and when to consider a hybrid strategy of BVS in combination with DES or drug-coated balloons.

A hybrid strategy with bioresorbable vascular scaffolds and drug eluting stents for treating complex coronary lesions

BACKGROUND

Due to the inherent limitations of current generation BVSs, complex coronary artery disease often contains BVS unsuitable segments. Our aim was to assess the feasibility of a hybrid approach using bioresorbable vascular scaffolds (BVSs) and drug-eluting stents (DESs) for the treatment of complex coronary artery lesions not suitable for a scaffolding only approach.

METHODS

A retrospective multicenter cohort analysis was performed on patients with complex de novo or in-stent restenosis lesions treated with a hybrid BVS (Absorb BVS, Abbott Vascular, Santa Clara, CA) and DES strategy. The primary endpoint was target lesion failure (TLF) defined as a composite of cardiac death, target-vessel myocardial infarction (MI) and target lesion revascularization (TLR).

RESULTS

A total of 98 patients (105 lesions) were treated with the hybrid strategy. Isolated long lesions in which either proximal or distal reference vessel diameters were not suitable for BVS were an indication in 36.2% (n=38) of cases. In contrast, 28% (n=29) of lesions treated with the hybrid strategy were bifurcations in which the side branch was predominantly treated with DES (n=28). DES bailout after BVS implantation was an indication in 21.9% (n=23 lesions). The rates of type B2/C and long lesions (>28mm) were 95.2% and 74.3% respectively. The mean total BVS and DES lengths implanted were 37.5±24.1mm and 25.0±14.7mm respectively. The rate of TLF in the overall cohort of patients (median follow-up 405days [interquartile range 189-658]) was 11.4% at 1-year. This was primarily driven by TLR (9.5%), with rates of cardiac death and target vessel MI of 2.1% and 1.4% respectively. No cases of definite or probable BVS/DES thrombosis occurred.

CONCLUSION

In conclusion, the use of a hybrid BVS/DES strategy was feasible and associated with acceptable outcomes at 1-year, considering the length and complexity of lesions treated. Further, larger studies with longer follow-up are needed to confirm our findings.

Bioresorbable Scaffolds for Coronary Stenosis: When and How Based Upon Current Studies

PURPOSE OF REVIEW

First-generation bioresorbable scaffolds (BRS), largely represented by the poly-l-lactic acid (PLLA) ABSORB (Abbott Vascular, Temecula, Illinois, US), have demonstrated, in low to moderate lesion complexity, similar efficacy to current generation metallic drug-eluting stents. However, a trend toward more device thrombosis has been observed, especially when the scaffolds are used in off-label situations. In this review, we address the most relevant drawbacks of these devices and, based on the available scientific data, we visit the scenarios where there is more uncertainty about their indication, trying to identify the lesions/patients to whom this technology should be voided at its current stage of development.

RECENT FINDINGS

Based on available data from randomized trials and observational real world registries, the use of first generation BRS has been associated with a trend to higher acute/subacute thrombosis rate, which might be partially explained by the peculiarities related to their deployment technique, such as the need for precise vessel sizing and caution on post-dilation. Special attention should be paid when using these devices to treat small coronary arteries (<2.5 mm), long lesions requiring overlapping, and patients with acute coronary syndrome, in particular those with ST-segment elevation myocardial infarction (STEMI). Finally, the role of these devices is still uncertain in more complex lesion anatomies such as bifurcations, ostial lesions, etc. Although based on attractive clinical premises, the current indications of BRS are still limited by significant drawbacks observed in the first generation of these devices. Of note, new generation scaffolds are currently in preclinical and clinical evaluation and present features that might surpass most of these limitations.