Outcomes of Optimised Implantation Technique with Bioresorbable scaffolds: A Pooled Analysis of ABSORB-IV and COMPARE-ABSORB Trials

Randomised trials have demonstrated higher midterm rates of adverse events and device thrombosis with Absorb-BVS compared to contemporary drug-eluting-stents (DES). BVS failure was ascribed to the implantation technique and consequently two large randomised trials evaluated the clinical impact of an optimised scaffold-implant-procedure. However, pooling together data from ABSORB-IV and those of the COMPARE-ABSORB, the scaffold was still associated with a statistically significant increased risk of target-vessel myocardial-infarction (OR 1.5; 95% CI 1.04-2.17; P = 0.03) and thrombotic events (OR 2.85; 95% CI 1.33-6.11; P = 0.007) at 1-year. Such kind of results could be in part attributed to a lower radial force and the higher acute recoil of the BVS as observed in previous studies. Besides a painstaking implantation technique, future generations of bioresorbable stents should incorporate an excellent mechanical propriety in order to compete with the current-generation DES.

Coronary Shear Stress after Implantation of Bioresorbable Scaffolds – a Modern Interdisciplinary Concept at the Border between Interventional Cardiology and Cardiac Imaging

Bioresorbable scaffolds/stents offer new and exciting perspectives in the treatment of patients with acute coronary syndromes, especially after the recent development of invasive imaging techniques, such as optical coherence tomography, which allow complete assessment of vascu-lar segments. A particular advantage of bioresorbable scaffolds is that once the biosorption of the scaffold is complete, the vascular segment regains its normal physiological functions, thus eliminating the risk of late complications. New studies show the importance of shear stress in the progression of vascular atherosclerosis or in accelerating endothelial turnover. Based on the current knowledge in this field, a future standardized determination of shear stress may help in the long-term follow-up of patients that have suffered or are at risk of developing an acute coronary syndrome.

Hybrid Coronary Percutaneous Treatment with Metallic Stents and Everolimus-Eluting Bioresorbable Vascular Scaffolds: 2-years Results from the GABI-R Registry

The limitations of the first-generation everolimus-eluting coronary bioresorbable vascular scaffolds (BVS) have been demonstrated in several randomized controlled trials. Little data are available regarding the outcomes of patients receiving hybrid stenting with both BVS and drug-eluting stents (DES). Of 3144 patients prospectively enrolled in the GABI-Registry, 435 (age 62 ± 10, 19% females, 970 lesions) received at least one BVS and one metal stent (hybrid group). These patients were compared with the remaining 2709 (3308 lesions) who received BVS-only. Patients who had received hybrid stenting had more frequently a history of cardiovascular disease and revascularization (p < 0.05), had less frequently single-vessel disease (p < 0.0001), and the lesions treated in these patients were longer (p < 0.0001) and more frequently complex. Accordingly, the incidence of periprocedural myocardial infarction (p < 0.05) and that of cardiovascular death, target vessel and lesion failure and any PCI at 24 months was lower in the BVS-only group (all p < 0.05). The 24-months rate of definite and probable scaffold thrombosis was 2.7% in the hybrid group and 2.8% in the BVS-only group, that of stent thrombosis in the hybrid group was 1.86%. In multivariable analysis, only implantation in bifurcation lesions emerged as a predictor of device thrombosis, while the device type was not associated with this outcome (p = 0.21). The higher incidence of events in patients receiving hybrid stenting reflects the higher complexity of the lesions in these patients; in patients treated with a hybrid strategy, the type of device implanted did not influence patients´ outcomes.

Bioresorbable Scaffold for Treatment of Coronary Artery Lesions: Intravascular Ultrasound Results From the ABSORB Japan Trial

OBJECTIVES

The aim of this study was to characterize post-procedural intravascular ultrasound (IVUS) findings in the ABSORB Japan trial, specifically stratified by the size of target coronary arteries.

BACKGROUND

Despite overall noninferiority confirmed in recent randomized trials comparing bioresorbable vascular scaffolds (BVS) (Absorb BVS) and cobalt-chromium everolimus-eluting metallic stents (CoCr-EES), higher event rates of Absorb BVS have been reported with suboptimal deployment, especially in small coronary arteries.

METHODS

In the ABSORB Japan trial, 150 patients (2:1 randomization) were scheduled in the IVUS cohort. Small vessel was defined as mean reference lumen diameter <2.75 mm. Tapered-vessel lesions were defined as tapering index (proximal/distal reference lumen diameter) ≥1.2.

RESULTS

Overall, IVUS revealed that the Absorb BVS arm had smaller device expansion than the CoCr-EES arm did, which was particularly prominent in small- and tapered-vessel lesions. Higher tapering index was also associated with higher rates of incomplete strut apposition in Absorb BVS, but not in CoCr-EES. With respect to procedural techniques, small-vessel lesions were treated more frequently with noncompliant balloons at post-dilatation but using significantly lower pressure in the Absorb BVS arm. In contrast, tapered-vessel lesions were post-dilated at equivalent pressure but with significantly smaller balloon catheters in the Absorb BVS arm, compared with the CoCr-EES arm.

CONCLUSIONS

The significantly smaller device expansion especially in small vessels may account for the poorer outcomes of Absorb BVS in this lesion type. Appropriate optimization strategy, possibly different between polymeric and metallic devices, needs to be established for bioresorbable scaffold technology. (AVJ-301 Clinical Trial: A Clinical Evaluation of AVJ-301 Absorb™ BVS) in Japanese Population [ABSORB JAPAN]; NCT01844284).

Three-year outcome of everolimus-eluting bioresorbable vascular scaffold versus everolimus-eluting metallic stents: a comprehensive updated meta-analysis of randomized controlled trials

INTRODUCTION

In recent years, everolimus-eluting bioresorbable vascular scaffold stents (EE-BRS) were developed as alternative to everolimus-eluting metallic stents (EES) for coronary artery disease (CAD) treatments. Areas covered: Searches were conducted in MEDLINE, EMBASE, EBSCO, Springer, Ovid, TCTMD, Cardiosource, Clinical Trial Results and the Cochrane Library with combined key words such as bioresorbable vascular scaffold (BVS), everolimus-eluting metallic stents, EES, coronary artery disease, CAD and randomized-Controlled Trials.Finally, 5,474 patients were enrolled for comparison of device-induced thrombosis, ischemia-driven target lesion revascularization (ID-TLR), device-oriented composite endpoints (DOCE), patient-oriented composite endpoints (POCE), and target vessel failure (TVF) between EE-BRS and EES treatments. The primary literature search retrieved 200 records. Expert Opinion: There was no difference regarding DOCEs, POCEs and ID-TLRs for 1 or 2 years, whereas there were significant differences regarding thrombosis between EE-BRS and EES interventions in the 1-year (pooled HR, 2.15, 95%CI: 1.11, 4.18) and 2-year follow-ups (pooled HR, 2.02, 95%CI: 1.08, 3.78), but not in the 3-year follow-up (pooled HR, 1.57, 95%CI: 0.66, 3.75) anymore. The results of this study showed no inferiority of EE-BRS regarding TVF, DOCE, POCE and ID-TLR 1-year and 2-years after interventions, but enhanced risk of thrombosis in the EE-BRS patients, which disappeared in 3-year follow-ups.

Long-term safety of bioresorbable scaffolds: insights from a network meta-analysis including 91 trials

AIMS

The aim of this study was to investigate the long-term safety and efficacy of biodegradable scaffolds and metallic stents.

METHODS AND RESULTS

We analysed a total of 91 randomised controlled trials with a mean follow-up of 3.7 years in 105,842 patients which compared two or more coronary metallic stents or biodegradable scaffolds and reported the long-term clinical outcomes (≥2 years). Network meta-analysis showed that patients treated with the Absorb bioresorbable vascular scaffold (BVS) had a significantly higher risk of definite or probable scaffold thrombosis (ScT) compared to those treated with metallic DES. The risk of very late ScT was highest with the Absorb BVS among comparators. Pairwise conventional meta-analysis demonstrated that the elevated risk of ScT with Absorb BVS compared to cobalt-chromium everolimus-eluting stents was consistent across the time points of ≤30 days (early), 31 days - 1 year (late) and >1 year (very late) ScT. In addition, target lesion failure rates were significantly higher in the Absorb BVS cohort, driven by both increased risk of target vessel myocardial infarction and ischaemia-driven target lesion revascularisation.

CONCLUSIONS

Absorb BVS implantation was associated with increased risk of long-term and very late ScT compared to current-generation metallic DES. The risk of ScT occurred with a rising trend beyond one year.

Everolimus-eluting bioresorbable vascular scaffolds: learning from the past to improve the future

Bioresorbable vascular scaffolds (BVS) were developed to overcome the long-term limitations of metallic drug-eluting stents (DES). Shortcomings of DES include their permanent metallic cage which prevents normal coronary vasomotion, vascular remodeling, precludes future bypass grafting, and creates a nidus for very late stent thrombosis. With its transient scaffold which provides early mechanical support and subsequently resorbs thereby restoring physiologic properties and architecture of the vasculature, BVS offers a promising development within the field of interventional cardiology. Even though various BVS have been or are currently under development, the ABSORB BVS from Abbott Vascular was the first FDA approved device. In this review, we shed light on shortcomings of the current generation DES and theoretical advantages of BVS. In addition, we will discuss in detail clinical data from observational studies, meta-analyses, registries, and randomized controlled trials as it pertains to the efficacy and safety outcomes with everolimus-eluting BVS as compared to the current generation everolimus-eluting metallic stents (EES). We will summarize reasons behind the disappointing results from clinical trials and the failure of first generation BVS leading to its withdrawal from the market. Lastly, we will briefly review ongoing developments with the newer-generation BVS and future pre-clinical and clinical studies that are underway to evaluate the efficacy and safety of second-generation BVS.

Predictors of bioresorbable scaffold failure in STEMI patients at 3 years follow-up

BACKGROUND

Little data are available on the long-term outcomes of bioresorbable scaffold (BRS) in the setting of ST-segment elevation myocardial infarction (STEMI). The aim of this study is to investigate three-years outcomes and predictors of BRS failure in patients presenting with STEMI.

METHODS AND RESULTS

Two prospective, single-arm registries were pooled. Incidence and predictors of clinical outcome were assessed with Kaplan-Meier and Cox regression analyses. From May-2012 to January-2015, 183 STEMI patients (58 ± 13 years, 77% males, 29% diabetics) who received a total of 256 BRS (1.4 ± 0.8 per patient) were included. 248 patients (65 ± 11 years, 74% males, 27% diabetics) treated for stable coronary artery disease (SCAD) served as control. 3-years follow-up was available in 386 (90%) patients. Device-oriented composite endpoint and scaffold thrombosis (ScT) rates were similar in the two groups (STEMI: 11.5% vs SCAD: 12.9%, P = 0.84; STEMI: 3.6% vs SCAD: 3.3%, P = 0.90). While early ScT was more frequent in SCAD patients, late/very late ScT was a feature of STEMI. While in STEMI patients the incidence of ScT was higher in vessels with RVD > 3.5 mm, a RVD < 2.5 mm was a predictor of events in stable patients. Similarly, BRS undersizing predicted events in STEMI patients, while oversizing was a predictor in stable ones. Finally, the incidence of ScT was reduced in both STEMI and stable patients (from 6.3% to 0% and from 5.80% to 0.9%) when an optimized implantation technique was used.

CONCLUSIONS

The incidence of events for three years follow-up was similar in STEMI and SCAD patients, although different timing and features underlie ScT in the two groups.

Clinical results of bioresorbable drug-eluting scaffolds in short and long coronary artery lesions using the PSP technique

BACKGROUND

Data on bioresorbable vascular scaffolds (BVS) for the treatment of long lesions are limited. We studied the use of BVS-Absorb in routine clinical practice and compared the outcome of long lesions with short lesions. Implantation of drug-eluting scaffolds without PSP-technique (predilation, proper sizing and postdilation) is associated with an increased thrombotic risk. We compared the long-term outcome up to 36 months of patients with short (< 20 mm) and long (≥20 mm) coronary artery lesions after implantation of bioresorbable vascular scaffolds (BVS) via PSP-technique.

METHODS

Three hundred twenty-six patients with 424 lesions were enrolled in this prospective study and underwent percutaneous coronary intervention with the Absorb BVS. Clinical follow-up was scheduled after 12, 24 and 36 months. In all lesions the PSP-technique was used. The device oriented composite endpoint (DOCE) was defined as cardiac death, myocardial infarction (MI) not clearly related to a non-target vessel and target lesion revascularization (TLR).

RESULTS

Kaplan-Meier estimates for DOCE after 12 months were 2.63% for short lesions and 8.09% for long lesions (p = 0.0131), 5.51% vs. 11.35% (p = 0.0503) after 24 months and 8.00% vs. 18.00% (p = 0.0264) after 36 months of clinical follow-up. Kaplan-Meier estimates for TLR after 12 months were 1.46% for short and 7.69% for long lesions (p = 0.0012), 2.06% vs. 8.75% after 24 months (p = 0.0027) and 4.96% vs. 9.59% after 36 months of follow-up (p = 0.0109). Scaffold thrombosis rates were low.

CONCLUSIONS

In long lesions compared to short ones the bioresorbable scaffold Absorb implanted with the proper PSP technique Absorb has significant higher rates of DOCE.

THE LEVEL OF EVIDENCE

Is 3 (non-random sample).

Bioresorbable Vascular Scaffold Compared With Minimally Invasive Bypass Surgery for the Left Anterior Descending Coronary Artery Disease: 12-Month Follow up

THE AIM

Evaluates long-term clinical outcomes of percutaneous coronary intervention (PCI) with bioresorbable vascular scaffold (BVS) versus minimally invasive direct coronary artery bypass (MIDCAB) surgery for the treatment of left anterior descending (LAD) lesions.

METHODS AND RESULTS

In this single-center study were included 130 patients with stable angina and significant (≥ 70 %) LAD disease. Patients were randomly assigned in a 1:1 ratio to PCI with everolimus-eluting BVS (n=65) or MIDCAB (n=65). The primary end-point was major adverse cerebro-cardiovascular events (MACCE) and secondary was scaffold (graft) thrombosis at 1 year. The groups of patients were comparable for all baseline demographic, clinical and angiographic parameters. MACCE at 12 month occurred in 9.2 % of patients in the BVS group and in 4.6 % of patients in the MIDCAB group (p=0.3). There was no significant difference between the groups in rates of all cause death (1.5 % vs 1.5 %, p=1.0), myocardial infarction (3.1 % vs. 6.1 %, p=0.4), any revascularization (1.5 % vs. 6.1 %, p=0.1) and scaffold (graft) thrombosis (1.5 % vs. 1.5 %, p=1.00).

CONCLUSION

At 12-month follow up, there was no significant difference in the rate of MACCE between PCI by BVS and MIDCAB in patients with isolated LAD lesions.

Multislice computed tomography assessment of everolimus-eluting Absorb bioresorbable scaffolds in comparison with metallic drug-eluting stents from the ABSORB Japan randomised trial

AIMS

Blooming artefacts limit accurate coronary assessment by multislice computed tomography (MSCT) in metallic stents. We sought to investigate whether bioresorbable vascular scaffolds (BVS) could be better assessed by MSCT.

METHODS AND RESULTS

Among 400 patients in the randomised ABSORB Japan trial, a pre-specified MSCT substudy was performed in 98 patients (103 lesions) in the BVS arm and 49 patients (49 lesions) in the cobalt-chromium everolimus-eluting stent (CoCr-EES) arm at 13 months prior to follow-up angiography. The assessability of BVS by MSCT was superior to that of CoCr-EES (94% versus 67%, p<0.001). Blooming artefacts were the main reason CoCr-EES could not be analysed (29%), while marker artefacts precluded analysis in 1.1% of BVS. In the CoCr-EES arm, non-assessable lesions were more prevalent in segments with 2.5 mm stents compared to 3.0 or 3.5 mm stents (75.0% versus 23.5%, p=0.01), while in the BVS arm image quality was good regardless of the diameter. The in-device minimal lumen diameter by MSCT was smaller than that by QCA with a difference of 0.61 mm in the CoCr-EES arm, vs. only 0.026 mm in the BVS arm.

CONCLUSIONS

The feasibility of MSCT assessment of BVS-treated lesions was greater than that for lesions with CoCr-EES.

Three-year clinical outcomes of patients treated with everolimus-eluting bioresorbable vascular scaffolds: Final results of the ABSORB EXTEND trial

BACKGROUND

There is still limited data on the very long term clinical outcomes after ABSORB BRS in daily practice. We sought to evaluate the 3 year-performance of the Absorb bioresorbable vascular scaffolds for the treatment of low/moderate complexity patients enrolled in the ABSORB EXTEND trial.

METHODS

ABSORB EXTEND is a prospective, single-arm, open-label clinical study in which 812 patients were enrolled at 56 sites. This study allowed the treatment of lesions ≤28 mm in length and reference vessel diameter of 2.0-3.8 mm (as assessed by on-line QCA). To determine the independent predictors of MACE, a multivariable logistic regression model was built using a stepwise (forward/backward) procedure.

RESULTS

Average population age was 61 years and 26.5% had diabetes. Most patients had single target lesion (92.4%). Adequate scaffold deployment (PSP) was achieved in 14.2% of the cases. At three years, the composite endpoints of MACE and ischemia-driven target vessel failure were 9.2% and 10.6%, respectively. The cumulative rate of ARC definite/probable thrombosis was 2.2%, with 1.2% of the cases occurring after the 1st year. Independent predictors of MACE were hypertension and the need for "bail out" stent.

CONCLUSION

At three-year follow-up, the use of ABSORB in low/moderate complex PCI was associated with low and acceptable rates of major adverse clinical events, despite the infrequent use of the recommended contemporary scaffold deployment technique. However, scaffold thrombosis rate was higher than reported with current generation of metallic DES. The study is registered on clinicaltrials.gov (unique identifier NCT01023789).

Long-term outcome of first 300 implanted Absorb bioresorbable vascular scaffolds in an all-comers Middle East population

Objectives

To evaluate long-term clinical outcomes of the Absorb bioresorbable vascular scaffold (BVS) system (Abbott Vascular) in an all-comers Middle East population.

Methods

This prospective registry study included an initial set of patients with coronary lesions treated using Absorb BVS. Patients were followed for target vessel failure (TVF) including cardiac death, target vessel myocardial infarction (MI), and target lesion revascularization.

Results

A total of 217 patients (age, 55 ± 11 years; male, 169) with 300 treated lesions were included (median follow-up, 36 months [range, 26–41 months]; complete follow-up, 201 patients). Diabetes mellitus and acute coronary syndrome were present in 50% and 57% of patients, respectively. TVF rate was 32/201 (15.9%), including cardiac death in 10 (5%), target vessel MI in 13 (6.5%), and target lesion revascularization in 22 patients (10.9%). Definite or probable device thrombosis occurred in 11/201 patients (5.5%). TVF was associated with heart failure, worse ejection fraction, multi-vessel BVS, multi BVS in lesion, and total BVS length >50 mm.

Conclusions

Long-term outcome following Absorb BVS implantation in a population with high prevalence of high-risk and complex patients is acceptable, but heart failure, worse ejection fraction, and multi-vessel or long BVS implantation were associated with worse outcomes.

Three-Year Results of the Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Infrapopliteal Arteries

Purpose: To investigate the midterm performance of the everolimus-eluting Absorb bioresorbable vascular scaffold (BVS) for the treatment of symptomatic infrapopliteal atherosclerotic disease. Methods: A single-center study prospectively enrolled 48 symptomatic patients (mean age 82.1±8.0 years; 27 men) between September 2013 and February 2018 to evaluate the Absorb everolimus-eluting BVS system in distal popliteal and tibial lesions. Mean lesion length was 20.1±10.8 mm. Following predilation, up to 2 BVS were implanted in target lesions in 55 limbs. Clinical and duplex ultrasound follow-up was performed at 1, 3, 6, 12, 24, 36, and 48 months to determine 30-day morbidity and midterm Kaplan-Meier estimates of binary restenosis, clinically-driven target lesion revascularization (CD-TLR), amputation, and mortality. Results: Seventy-one scaffolds were implanted to treat 61 lesions. Technical success was achieved in all patients, with no amputation, death, or target limb bypass surgery within 30 days of the index procedure. There was 1 early thrombotic occlusion of 2 BVS in a previously anticoagulated patient not given antiplatelet medication after the procedure. During a mean follow-up of 24.0±15.3 months, 11 (23%) patients died; the remaining 37 were available for follow-up. Binary restenosis (50%–75%) was detected in 6 (8%) scaffolds. Primary patency estimates at 12, 24, and 36 months were 92.2%, 90.3%, and 81.1%; freedom from CD-TLR estimates were 97.2%, 97.2%, and 87.3% at the same time points. No late scaffold thrombosis has been observed. The majority of the 55 limbs (51, 93%) were clinically improved; 4 (7%) were unchanged. Thirty-six (92%) of 39 limbs treated for tissue loss achieved complete wound healing, with no major amputation (limb salvage 100%). Conclusion: Midterm follow-up demonstrates excellent safety, patency, and freedom from CD-TLR rates using the Absorb bioresorbable vascular scaffold below the knee.

Cardiovascular stents: overview, evolution, and next generation

Compared to bare-metal stents (BMSs), drug-eluting stents (DESs) have been regarded as a revolutionary change in coronary artery diseases (CADs). Releasing pharmaceutical agents from the stent surface was a promising progress in the realm of cardiovascular stents. Despite supreme advantages over BMSs, in-stent restenosis (ISR) and long-term safety of DESs are still deemed ongoing concerns over clinically application of DESs. The failure of DESs for long-term clinical use is associated with following factors including permanent polymeric coating materials, metallic stent platforms, non-optimal drug releasing condition, and factors that have recently been supposed as contributory factors such as degradation products of polymers, metal ions due to erosion and degradation of metals and their alloys utilizing in some stents as metal frameworks. Discovering the direct relation between stent materials and associating adverse effects is a complicated process, and yet it has not been resolved. For clinical success it is of significant importance to optimize DES design and explore novel strategies to overcome all problems including inflammatory response, delay endothelialization, and sub-acute stent thrombosis (ST) simultaneously. In this work, scientific reports are reviewed particularly focusing on recent advancements in DES design which covers both potential improvements of existing and recently novel prototype stent fabrications. Covering a wide range of information from the BMSs to recent advancement, this study mostly sheds light on DES's concepts, namely stent composition, drug release mechanism, and coating techniques. This review further reports different forms of DES including fully biodegradable DESs, shape-memory ones, and polymer-free DESs.

Early experience and favorable clinical outcomes of everolimus-eluting bioresorbable scaffolds for coronary artery disease in Korea

BACKGROUND/AIMS

Compared with metallic drug-eluting stents (DES), bioresorbable vascular scaffolds (BVS) may further improve long-term outcomes of percutaneous coronary intervention (PCI) in patients with coronary artery disease. We report our early experience with BVS in Korea.

METHODS

We evaluated 105 consecutive patients with BVS implanted at Asan Medical Center, Korea between October 21, 2015 and June 3, 2016. Angiographic results, and in-hospital and 6-month clinical outcomes were assessed.

RESULTS

A total of 134 BVS were implanted to treat 115 lesions. The mean age was 62 ± 10.5 years; 85 patients (81%) were males, 26 patients (25%) were presented with acute coronary syndrome. Among 115 lesions treated with BVS, 76 (66.1%) were B2/C type, 27 (23.5%) were bifurcation lesions, and four (3.5%) were chronic total occlusion. Pre-dilation and post-dilation using high-pressure non-compliant balloon was performed in 104 lesions (90.4%) and 113 lesions (98.2%), respectively. During the procedure, intravascular imaging was used for all patients (100%; intravascular ultrasound 89 and optical coherence tomography 40 patients). Device success rate was 100%. In-segment and in-scaffold acute again were 1.1 ± 0.6 and 1.3 ± 0.5 mm, respectively. Periprocedural myocardial infraction occurred in four patients (3.8%). No deaths, stent thrombosis, or urgent revascularizations occurred either during hospitalization or the follow-up period.

CONCLUSION

In this single-center experience, implantation of BVS with intravascular imaging support was feasible and early clinical outcomes were excellent. Evaluation of long-term efficacy and safety of BVS and its feasibility in clinical use for a broader range of lesions is warranted.

Outcome of percutaneous coronary intervention with the Absorb bioresorbable scaffold: data from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR)

AIMS

Randomised trials indicate higher rates of stent thrombosis (ST) and target lesion failure (TLF) after percutaneous coronary intervention (PCI) with the Absorb bioresorbable scaffold (BRS) compared with modern drug-eluting stents (DES). We aimed to investigate the outcome of all Swedish patients treated with the Absorb BRS.

METHODS AND RESULTS

The Absorb BRS (n=810) was compared with commonly used modern DES (n=67,909). The main outcome measure was definite ST; mean follow-up was two years. Despite being implanted in a younger, lower-risk population compared with modern DES, the Absorb BRS was associated with a higher crude incidence of definite ST at stent level: 1.5 vs. 0.6%, hazard ratio (HR) 2.38 (95% confidence interval [CI]: 1.34-4.23), adjusted HR 4.34 (95% CI: 2.37-7.94); p<0.001. The patient level adjusted HR was 4.44 (95% CI: 2.25-8.77). Rates of in-stent restenosis were similar for BRS and DES. Non-compliance with dual antiplatelet therapy (DAPT) guidelines was noted in six out of 12 BRS ST events. Three very late ST events occurred with the Absorb BRS.

CONCLUSIONS

In this real-world observational study, the Absorb BRS was associated with a significantly higher risk of definite ST compared with modern DES. Non-compliance with DAPT guideline recommendations was common among Absorb definite ST events.

Implantation techniques (predilatation, sizing, and post-dilatation) and the incidence of scaffold thrombosis and revascularisation in lesions treated with an everolimus-eluting bioresorbable vascular scaffold: insights from the AIDA trial

AIMS

Specific implantation strategies have been proposed for the Absorb bioresorbable vascular scaffold (Absorb BVS) to optimise outcomes. We aimed to analyse whether the occurrence of definite scaffold thrombosis (ScT) and target lesion revascularisation (TLR) in Absorb-treated AIDA patients was influenced by scaffold implantation techniques.

METHODS AND RESULTS

Absorb BVS implantation in 1,074 lesions was graded according to definitions of optimal implantation based on predilatation, sizing, and post-dilatation (PSP). Lesion-oriented outcomes (definite ScT and TLR) that occurred during a median follow-up of 707 days were related to the presence or absence of PSP. Of 1,074 lesions, 158 (14.7%) lesions met PSP criteria. The most prevalent reason for not meeting PSP criteria was inadequate sizing: 863 (94.2%). Definite ScT occurred in four of 158 PSP-treated lesions compared with 27 of 916 non PSP-treated lesions, with two-year KM estimates of 3.0% vs. 4.1% and an HR of 1.14 (p=0.811). TLR occurred in eight of 158 PSP-treated lesions compared with 61 of 916 non PSP-treated lesions, with KM estimates of 5.6% vs. 7.1% and an HR of 1.29 (p=0.492).

CONCLUSIONS

In AIDA, lesions that underwent scaffold implantation according to an optimised Absorb BVS implantation technique did not have lower rates of ScT and TLR compared to scaffold-treated lesions that did not meet PSP criteria.

Meta-Analysis Comparing Outcomes After Everolimus-Eluting Bioresorbable Vascular Scaffolds Versus Everolimus-Eluting Metallic Stents in Patients with Acute Coronary Syndromes

Acute coronary syndromes (ACS) may represent an intriguing clinical scenario for implantation of bioresorbable vascular scaffold (BRS). Nevertheless, the knowledge about the performance of these devices in patients with ACS is limited. Therefore, we performed a meta-analysis of clinical studies aiming to assess the safety and efficacy of everolimus-eluting-BRS versus everolimus-eluting-metallic stents (EES) in ACS patients undergoing percutaneous coronary intervention. Six studies enrolling 2,318 patients were included and analyzed for the risk of primary safety outcome (stent or scaffold thrombosis [ST/ScT]), primary efficacy outcome (target lesion revascularisation [TLR]), and secondary outcomes (myocardial infarction, cardiac death, all-cause death). Median follow-up was 9.5 (6 to 19.5) months. Patients treated with BRS had a significantly higher risk of definite ST/ScT compared with those receiving EES (2.3% vs 1.08%, odds ratio [OR] 2.22, 95% confidence interval [CI] 1.10 to 4.45, p = 0.03, I2 = 0%). Similarly, the risk of TLR was significantly higher in the BRS compared with EES group (3.5% vs 2.5%, OR 1.79, 95% CI 1.02 to 3.16, p = 0.04, I2 = 0%). When TLRs due to thrombosis were excluded, the difference in risk estimates between the 2 groups was no longer significant (OR 1.19, 95% CI 0.48 to 2.98, p = 0.71, I2 = 25%). Risk for secondary endpoints did not differ between the 2 groups. Results were confirmed when clinical and procedural variables were tested as potential effect modifiers in the meta-regression analysis for both primary endpoints. In conclusion, compared with those receiving EES, patients with ACS treated with BRS had increased risk of definite device thrombosis and TLR at mid-term follow-up.

Comparison of the Absorb bioresorbable vascular scaffold to the Xience durable polymer everolimus-eluting metallic stent in routine clinical practice: a propensity score-matched analysis from a multicenter registry

INTRODUCTION

Most clinical trials related to bioresorbable vascular scaffold (BVS) technology are limited to a highly selected patient population.

AIM

To evaluate early and long-term clinical outcomes of the Absorb everolimus-eluting BVS compared to the everolimus-eluting metallic XIENCE V stent in routine clinical practice.

MATERIAL AND METHODS

This is a multicenter, retrospective propensity score-matched comparative study, comprising 76 patients treated with a bare metal stents (BMS) and 501 with a XIENCE stent. Patients included in the study had stable and unstable angina and both types of myocardial infarction (STEMI and NSTEMI) as an indication for intervention and at least one significant de novo lesion in native coronary arteries. The primary endpoint was major adverse cardiovascular event (MACE), defined as death, myocardial infarction (MI), or target vessel revascularization (TVR).

RESULTS

Median follow-up was 400 days in both groups. After propensity score matching for patient baseline characteristics, only higher rate of predilatation, predominantly treated left anterior descending artery (LAD) and lower number of used stents in the BVS group remained statistically significant. After adjustment there was no difference in type of treated lesions. The MACE rate did not differ between BVS and drug-eluting stents (DES) groups (7.2% vs. 11.15%, respectively; p = 0.17). The TVR was 2.9% in both groups. Except in the periprocedural period, there were no deaths or MI in the BVS group. There was no stent thrombosis in either studied group.

CONCLUSIONS

In routine clinical practice throughout long-term follow-up, clinical outcomes of patients who successfully received the Absorb BVS did not differ from those of patients who received the Xience stent. Longer follow-up data are required to determine whether these findings will persist beyond one year.

Effect of Post-Dilatation Following Primary PCI With Everolimus-Eluting Bioresorbable Scaffold Versus Everolimus-Eluting Metallic Stent Implantation: An Angiographic and Optical Coherence Tomography TROFI II Substudy

OBJECTIVES

This study sought to investigate the effect of post-dilatation on angiographic and intracoronary imaging parameters in the setting of primary percutaneous coronary intervention comparing the everolimus-eluting bioresorbable scaffold (BRS) with the everolimus-eluting metallic stent (EES).

BACKGROUND

Routine post-dilatation of BRS has been suggested to improve post-procedural angiographic and subsequent device-related clinical outcomes.

METHODS

In the ABSORB STEMI TROFI II trial, 191 patients with ST-segment elevation myocardial infarction were randomly assigned to treatment with BRS (n = 95) or EES (n = 96). Minimal lumen area and healing score as assessed by optical coherence tomography at 6 months were compared between BRS- and EES-treated patients stratified according to post-dilatation status.

RESULTS

Primary percutaneous coronary intervention with post-dilatation was performed in 48 (50.5%) BRS- and 25 (25.5%) EES-treated lesions. There were no differences in baseline characteristics and post-procedural minimal lumen diameter between groups. In the BRS group, lesions with post-dilatation were associated with a trend toward a smaller minimal lumen area at 6 months (5.07 ± 1.68 mm² vs. 5.72 ± 1.77 mm²; p = 0.09) and significantly larger angiographic late lumen loss (0.28 ± 0.34 mm vs. 0.12 ± 0.25 mm; p = 0.02), whereas no difference was observed in the EES arm (5.46 ± 2.18 mm² vs. 5.55 ± 1.77 mm²; p = 0.85). The neointimal healing score was low and comparable between groups with and without post-dilation (BRS: 1.55 ± 2.61 vs. 1.92 ± 2.17; p = 0.48; EES: 2.50 ± 3.33 vs. 2.90 ± 4.80; p = 0.72).

CONCLUSIONS

In the setting of selected patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention with BRS or EES, post-dilatation did not translate into larger lumen area or improved arterial healing at follow-up. (ABSORB STEMI: The TROFI II; NCT01986803).

Late thrombotic events after bioresorbable scaffold implantation: a systematic review and meta-analysis of randomized clinical trials

Aims

To compare the long-term safety and efficacy of bioresorbable vascular scaffold (BVS) with everolimus-eluting stent (EES) after percutaneous coronary interventions.

Methods and results

A systematic review and meta-analysis of randomized clinical trials comparing clinical outcomes of patients treated with BVS and EES with at least 24 months follow-up was performed. Adjusted random-effect model by the Knapp-Hartung method was used to compute odds ratios (OR) and 95% confidence intervals (CI). The primary safety outcome of interest was the risk of definite/probable device thrombosis (DT). The primary efficacy outcome of interest was the risk of target lesion failure (TLF). Five randomized clinical trials (n = 1730) were included. Patients treated with Absorb BVS had a higher risk of definite/probable DT compared with patients treated with EES (OR 2.93, 95%CI 1.37-6.26, P = 0.01). Very late DT (VLDT) occurred in 13 patients [12/996 (1.4%, 95%CI: 0.08-2.5) Absorb BVS vs. 1/701 (0.5%, 95%CI: 0.2-1.6) EES; OR 3.04; 95%CI 1.2-7.68, P = 0.03], 92% of the VLDT in the BVS group occurred in the absence of dual antiplatelet therapy (DAPT). Patients treated with Absorb BVS had a trend towards higher risk of TLF (OR 1.48, 95%CI 0.90-2.42, P = 0.09), driven by a higher risk of target vessel myocardial infarction and ischaemia-driven target lesion revascularization. No difference was found in the risk of cardiac death.

Conclusion

Compared with EES, the use of Absorb BVS was associated with a higher rate of DT and a trend towards higher risk of TLF. VLDT occurred in 1.4% of the patients, the majority of these events occurred in the absence of DAPT.

Serial 5-Year Evaluation of Side Branches Jailed by Bioresorbable Vascular Scaffolds Using 3-Dimensional Optical Coherence Tomography: Insights From the ABSORB Cohort B Trial (A Clinical Evaluation of the Bioabsorbable Everolimus Eluting Coronary Stent System in the Treatment of Patients With De Novo Native Coronary Artery Lesions)

BACKGROUND

The long-term fate of Absorb bioresorbable vascular scaffold (Abbott Vascular, Santa Clara, CA) struts jailing side branch ostia has not been clarified. We therefore evaluate serially (post-procedure and at 6 months, 1, 2, 3, and 5 years) the appearance and fate of jailed Absorb bioresorbable vascular scaffold struts.

METHODS AND RESULTS

We performed 3-dimensional optical coherence tomographic analysis of the ABSORB Cohort B trial (A Clinical Evaluation of the Bioabsorbable Everolimus Eluting Coronary Stent System in the Treatment of Patients With De Novo Native Coronary Artery Lesions) up to 5 years using a novel, validated cut-plane analysis method. We included 29 patients with a total of 85 side branch ostia. From the 12 ostia which could be assessed in true serial fashion, 7 showed a pattern of initial decrease in the ostial area free from struts, followed by an increase in strut-free ostial area toward the end of the 5 years of follow-up. In a repeated-measures analysis with time as fixed variable and ostial area free from struts as dependent variable, we showed a numeric decrease in the estimated ostial area free from struts from 0.75 mm² (baseline) to 0.68 mm² (first follow-up visit at 6 months or 1 year) and 0.63 mm² (second follow-up visit at 2 or 3 years). However, from the second visit to the 5-year follow-up visit, there was a statistically significant increase from 0.63 to 0.89 mm² (P=0.001). Struts overlying an ostium divided the ostium into compartments, and the number of these compartments decreased over time.

CONCLUSIONS

This study showed that in most cases, the side branch ostial area free from struts initially decreased. However, with full scaffold bioresorption, the ostial area free from scaffold increased between 2 to 3 years and 5 years in the vast majority of patients.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00856856.

Comparison of Acute Thrombogenicity for Metallic and Polymeric Bioabsorbable Scaffolds: Magmaris Versus Absorb in a Porcine Arteriovenous Shunt Model

BACKGROUND

A comparison in acute thrombogenicity between the Magmaris sirolimus-eluting bioabsorbable magnesium scaffold and the Absorb bioresorbable vascular scaffold has not been performed. This study assessed acute thrombogenicity of Magmaris compared with Absorb and the Orsiro hybrid drug-eluting stent in a porcine arteriovenous shunt model.

METHODS AND RESULTS

An ex vivo porcine carotid jugular arteriovenous shunt was established and connected to SYLGARD tubing containing the Magmaris, Absorb, and Orsiro scaffolds/stents and allowed to run in the shunt for a maximum of 1 hour. Twelve shunts (2 shunt runs per pig) were run comparing the 3 scaffolds in alternating order. Nested generalized linear mixed models were used to compare variables between scaffold groups while adjusting for variability between shunt runs. Confocal fluorescent microscopy costaining CD61/CD42b demonstrated that both Magmaris (3.0%) and Orsiro (4.6%) had less platelet coverage of the total scaffold compared with Absorb (21.8%). Scanning electron microscopy demonstrated significantly less thrombus deposition to Magmaris as a percentage of the total scaffold compared with Absorb (5.0% versus 16.1%, P=0.02). Magmaris had significantly less PM-1-positive neutrophil and CD14-positive monocyte adherence compared with both Orsiro and Absorb. Orsiro had significantly less monocyte deposition compared with Absorb.

CONCLUSIONS

Despite a similar scaffold strut thickness, the Magmaris sirolimus-eluting bioabsorbable magnesium scaffold was significantly less thrombogenic compared with the Absorb bioresorbable vascular scaffold in an ex vivo porcine arteriovenous shunt model. Further studies are needed to determine whether the reduced thrombogenicity of Magmaris will result in reductions in major cardiovascular events.

Transradial experience with bioresorbable vascular scaffolds: A case-matched study with metallic drug-eluting stents

BACKGROUND

Whether polymeric bioresorbable vascular scaffolds (BVS) implantation with transradial approach is feasible and safe is unknown. We compared the feasibility and safety of the transradial approach for BVS delivery with metallic drug-eluting stents (DES).

METHODS

We identified 118 consecutive patients who underwent BVS implantation and we compared 30-days and 1-year results with 118 matched patients with DES. Patients were matched for age, sex, risk factors and clinical indication.

RESULTS

Rates of transradial approach were 98% in the BVS group vs 95% in the DES group (P = 0.16) with 5Fr used in 38% and 32% (P = 0.34), respectively. The number of stents was similar in both groups, 2.6 ± 1.5 vs 2.4 ± 1.3 (P = 0.23). Although maximal pressure for stent deployment was identical in both groups (16 ± 3 atm), more lesions were pre-dilated (83% vs 52%, P < 0.001) and post-dilated (71% vs 33%, P < 0.001) in the BVS group. Contrast volume (217 ± 97 vs 175 ± 108 ml, P < 0.001), fluoroscopy time (16 [10-23] vs 13 [8-21] min, P = 0.04) and procedure duration (65 ± 31 vs 56 ± 47 min, P = 0.045) were significantly higher in the BVS group. Major adverse cardiac events, including death, myocardial infarction and target vessel revascularization remained similar in both groups, 1.7% vs 0.8% (P = 0.56) at 30 days and 10% vs 8.5% (P = 0.66) at 1 year. At 1 year, stent thrombosis occurred in 2 (1.7%) patients in the BVS group and 1 (0.8%) patient in the DES group (P = 0.56).

CONCLUSION

The use of transradial approach for BVS compared to DES implantation was feasible and safe in all-comers, although BVS implantation included more technical challenges. Outcomes up to 1-year remained comparable in both groups.

Bioresorbable Scaffolds in Coronary Intervention: Unmet Needs and Evolution

Bioresorbable scaffolds (BRS) represent a novel paradigm in the 40-year history of interventional cardiology. Restoration of cyclic pulsatility and physiologic vasomotion, adaptive vascular remodeling, plaque regression, and removal of the trigger for late adverse events are expected BRS benefits over current metallic drug-eluting stents. However, first-generation BRS devices have significant manufacturing limitations and rely on optimal implantation technique to avoid experiencing an excess of clinical events. There are currently at least 22 BRS devices in different stages of development, including many trials of device iterations with thinner (<150 µm) struts than first-generation BRS. This article reviews the outcomes of commercially available and potentially upcoming BRS, focusing on the most recent stages of clinical development and future directions for each scaffold type.

Impact of calcium on procedural and clinical outcomes in lesions treated with bioresorbable vascular scaffolds - A prospective BRS registry study

BACKGROUND

There is limited data on the impact of calcium (Ca) on acute procedural and clinical outcomes in patients with lesions treated with bioresorbable vascular scaffolds (BRS). We sought to evaluate the effect of calcium on procedural and clinical outcomes in a 'real world' population.

METHODS

Clinical outcomes were compared between patients with at least 1 moderately or heavily calcified lesion (Ca) and patients with no/mild calcified lesions (non-Ca) enrolled in our institutional BRS registry.

RESULTS

455 patients (N) with 548 lesions (L) treated with 735 BRS were studied. Patients in the Ca group (N=160, L=200) had more complex (AHA B2/C lesion: 69.0% in Ca vs 14.9% in non-Ca, p<0.001) and significantly longer lesions (27.80±15.27 vs 19.48±9.92mm, p<0.001). Overall device success rate was 99.1% with no significant differences between the groups. Despite more aggressive lesion preparation and postdilation compared to non Ca, acute lumen gain was significantly less in Ca lesions (1.50±0.66 vs 1.62±0.69mm, p=0.040) with lower final MLD (2.28±0.41 vs 2.36±0.43, p=0.046). There were no significant differences in all-cause mortality, total definite scaffold thrombosis (ST), target lesion revascularization and myocardial infarction between the 2 groups. Late ST was more frequent in the Ca group compared to non Ca group (late ST: 2.1 vs 0%, p=0.02).

CONCLUSIONS

Clinical outcomes after BRS implantation in calcified and non-calcified lesions were similar. A remarkable difference in timing of thrombosis was observed, with an increased rate of late thrombosis in calcified lesions.

Thirty-Day and One-Year Clinical Outcomes of Bioresorbable Vascular Scaffold Implantation: A Single-Center Experience

Background

Available data on the use of the Bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, CA) in real-world patients is limited, particularly in Asian populations. The aim of this study was to assess clinical outcomes of patients treated with a BVS in real-world practice in Taiwan.

Methods

This study focused on 156 patients with coronary artery disease and a total of 249 lesions who received BVS implantation from October 2012 to October 2015. The study's primary endpoint was major adverse cardiac event (MACE), such as a myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), definite or possible scaffold thrombosis, cardiovascular death, and all-cause mortality during the thirty-day follow-up period. The secondary endpoint was MACE during the one-year follow-up period. Additionally, the composite clinical secondary endpoint was target lesion failure (TLF), which was called device-oriented composite endpoint.

Results

The average age of the patients was 60.34 ± 10.15 years, and 81.4% were male. The average of Syntax score was 12.42 ± 8.77 points. 44.2 % lesions were type B2 or C. At 31 days, one patient experienced a MACE (1/156) the composite of two TLF (2/249) with ST elevation MI, which was related to scaffold thrombosis. At one-year, 5.1 % (8/156) of the patients experienced a MACE and 3.6% (9/249) of the lesions experienced a TLF. There was no cardiovascular or all-cause mortality in the 30-day follow-up. The one-year cardiovascular and all-cause mortality rates were each 1.3%, respectively. Diabetes, ostial lesion, bifurcation lesion, and non-standard dual anti-platelet therapy (DAPT) were the strong associations of one-year TLF.

Conclusions

Even with difficult and complex lesions of patients in this study, acceptable outcomes were achieved with low definite or possible scaffold thrombosis rates after BVS implantation. And despite anatomical issues, it is important to complete standard DAPT.

Coronary Bioresorbable Vascular Scaffold Use in the Treatment of Coronary Artery Disease

Bioresorbable vascular scaffolds (BVS) represent a promising novel approach for the treatment of coronary artery disease. BVS promise to address some of the well-known limitations of current drug-eluting stents, while providing a transient scaffolding of the vessel to prevent acute vessel closure/recoil. Drug elution by BVS prevents neointimal proliferation in a similar fashion to drug-eluting stents, and complete bioresorption is associated with late vessel lumen enlargement, plaque regression, and restoration of vasomotion. Based on the pathophysiological reasons and on the results derived from clinical studies, BVS are increasingly being used in clinical practice. The aim of this review is to provide an overview of the current evidence supporting the use of BVS in clinical practice. In particular, we will discuss the randomized controlled trials and registries evaluating the clinical outcome of these devices, with a special focus on their application in patients with acute coronary syndrome and in specific lesion subsets (bifurcations, chronic total occlusions, and in-stent restenosis).