Late acquired coronary aneurysm and restenosis after bioresorbable vascular scaffold implantation: a case report

Background

Although the technology of bioresorbable vascular scaffold (BVS) aroused the peak of interest a few years ago and currently remains available only as part of experimental research, patients who have had BVS implanted should be still carefully monitored to detect possible long-term complications.

Case summary

We present the case of a 47-year-old man who had received BVS implantation for ST-segment elevation myocardial infarction. Six years later, computed tomography coronary angiography (CTCA) demonstrated in-segment restenosis in between two newly formed coronary aneurysms at the site of the implanted BVS. The patient received successful optical coherence tomography-guided percutaneous intervention with a new metallic drug-eluting stent implantation.

Discussion

Our case demonstrates that coronary aneurysms can be well characterized with CTCA and are often incidentally discovered as they cause no symptoms. The incidence of coronary aneurysm at the site of a previously implanted BVS is not defined, and little is known about the pathophysiology and evolution of these lesions. Therefore, the decision to proceed with conservative management or intervention must be tailored to the clinical conditions of the patient, the anatomy, the rapidity of growth, and the possible thrombotic burden.

Safety and efficacy of everolimus-eluting bioresorbable vascular scaffold for cardiac allograft vasculopathy (CART)

BACKGROUND

Cardiac allograft vasculopathy (CAV) is still the main drawback of heart transplantation (HTx) and percutaneous coronary intervention (PCI) is a palliative measure because of the high incidence of failure.

OBJECTIVE

This study aimed to investigate the safety and efficacy of bioresorbable scaffolds (BRSs) as potential novel therapeutic tool for the treatment of coronary stenoses in CAV.

METHODS

This is a multicenter, single-arm, prospective, open-label study (CART, NCT02377648), that included patients affected by advanced CAV treated with PCI and second-generation ABSORB BRS (Abbott Vascular). The primary endpoint was the incidence of 12-month angiographic in-segment scaffold restenosis (ISSR). Secondary endpoints were the incidence of major adverse cardiac events (MACEs) at 12- and 36-month follow-up and the incidence of ISSR at 36 months. A paired intracoronary imaging analysis at baseline and follow-up was also performed.

RESULTS

Between 2015 and 2017 35 HTx patients were enrolled and treated for 44 coronary lesions with 51 BRSs. The primary endpoint occurred in 13.5% of the lesions (5/37), with a cumulative ISSR rate up to 3 years of 16.2% (6/37). Angiographic lumen loss was 0.40 ± 0.62 mm at 12 months and 0.53 ± 0.57 mm at 36 months. Overall survival rate was 91.4% and 74.3%, and MACEs incidence 14.2% and 31.4% at 12 and 36 months, respectively. At the paired intracoronary imaging analysis, a significant increase of the vessel external elastic membrane area in the treated segment and some progression of CAV proximally to the BRS were detected.

CONCLUSIONS

BRS-based PCI for the treatment of CAV is feasible and safe, with an ISSR incidence similar to what reported in retrospective studies with drug-eluting stents.

Long-term intracoronary imaging and physiological measurements of bioresorbable scaffolds and untreated atherosclerotic plaques

BACKGROUND

Bioresorbable scaffolds (BRS) provide the prospect of restoring the anatomic and physiologic characteristics of the vascular wall.

OBJECTIVE

This study sought to examine the long-term outcomes of BRS-based coronary intervention in a young population with diffuse and severe coronary atherosclerotic disease (CAD) and to compare the long-term evolution of treated segments versus the natural progression of untreated non-flow limiting stenoses.

METHODS

Observational, single-center cohort study that prospectively included patients that underwent percutaneous coronary intervention with implantation of ABSORB BRS (Abbott Vascular). The clinical endpoint was the incidence of device-oriented composite endpoint (DoCE) up to 5 years follow-up. A subgroup of patients with baseline intracoronary imaging assessment of long lesions and/or multivessel disease underwent elective angiographic (70 patients, 129 lesions) and intracoronary imaging (55 patients, 102 lesions) follow-up. Paired intravascular ultrasound (IVUS) and quantitative flow reserve (QFR) were analyzed.

RESULTS

Between 2012 and 2017, 159 patients (mean age 54.0 ± 11.1) with native CAD were treated with BRS on 247 lesions. Patients were mainly at their first cardiac event, mostly acute coronary syndromes (86.5%). At the median follow-up time of 56 months [41-65], DoCE occurred in 15/159 (9.4%) patients, while non-target vessel-oriented composite endpoint occurred in 16 patients (10.4%). A significant atherosclerotic progression was detected on residual non-flow limiting plaques as per IVUS and QFR assessment, while no significant change was detected in the treated segment.

CONCLUSIONS

Mild-to-moderate asymptomatic CAD progressed significantly at 5-year despite OMT. BRS-treated segments had a less aggressive progression at 5-year despite more severe and symptomatic CAD at baseline.

Impact of post-implantation time on bioresorbable vascular scaffold outcomes for type C versus non-type C coronary lesions: A longer-term study

BACKGROUND

We have demonstrated that bioresorbable vascular scaffold (BVS) for ACC/AHA type C lesions was associated with higher risks of long-term target lesion revascularization (TLR) and target lesion failure (TLF). We determined the specific time after which higher risks of BVS for type C lesions are reduced in a longer-term follow-up.

METHODS

We analyzed data of 457 patients (59 ± 12 years, 87% male) with 714 BVS implanted for 529 lesions and a median follow-up of 56.4 (48.6-62.6) months. Patients with BVS for at least one type C lesion (N = 177) at index intervention and all non-type C lesions (N = 280) were compared for TLF (cardiac death, target vessel myocardial infarction, TLR). We specified the interactions between the non-type C versus type C group and the event-free survival times dichotomized at 24, 30, 32, 33, 36, and 39 months respectively.

RESULTS

The type C group had more multivessel disease (86% versus 65%, p < 0.001), left anterior descending artery treated (68% versus 53%, p = 0.002), intravascular imaging used (48% vs. 25%, p < 0.001), and BVS (2.3 ± 0.9 vs. 1.1 ± 0.3, p < 0.001) implanted with a longer total length (57 ± 21 vs. 29 ± 8 mm, p < 0.001). The TLR or TLF was higher (both log-rank p < 0.05) in the type C than in the non-type C group. However, the risks of TLR (hazard ratio: 3.6, 95% CI = 1.1-11.6) and TLF (hazard ratio: 3.8, 95% CI = 1.2-12.1) for type C lesions only remained higher until 24 months post-BVS implantation.

CONCLUSION

BVS provides a longer-term advantage, particularly for type C lesions with the majority requiring long stenting.

Preclinical Evaluation of an Everolimus-Eluting Bioresorbable Vascular Scaffold Via a Long-Term Rabbit Iliac Artery Model

BACKGROUND

Biodegradable poly (l-lactic acid) (PLLA), a bio safe polymer with a large elastic modulus, is widely used in biodegradable medical devices. However, because of its poor mechanical properties, a PLLA strut must be made twice as thick as a metal strut for adequate blood vessel support. Therefore, the mechanical properties of a drug-eluting metal-based stents (MBS) and a bioresorbable vascular scaffolds (BVS) were evaluated and their safety and efficacy were examined via a long-term rabbit iliac artery model.

METHODS

The surface morphologies of the MBSs and BVSs were investigated via optical and scanning electron microscopy. An everolimus-eluting (EE) BVS or an EE-MBS was implanted into rabbit iliac arteries at a 1.1:1 stent-to-artery ratio. Twelve months afterward, stented iliac arteries from each group were analyzed via X-ray angiography, optical coherence tomography (OCT), and histopathologic evaluation.

RESULTS

Surface morphology analysis of the EE coating on the MBS confirmed that it was uniform and very thin (4.7 μm). Comparison of the mechanical properties of the EE-MBS and EE-BVS showed that the latter outperformed the former in all aspects (radial force (2.75 vs. 0.162 N/mm), foreshortening (0.24% vs. 1.9%), flexibility (0.52 vs. 0.19 N), and recoil (3.2% vs. 6.3%). At all time points, the percent area restenosis was increased in the EE-BVS group compared to the EE-MBS group. The OCT and histopathological analyses indicate no significant changes in strut thickness.

CONCLUSION

BVSs with thinner struts and shorter resorption times should be developed. A comparable long-term safety/efficacy evaluation after complete absorption of BVSs should be conducted.

Five-year clinical outcomes using the bioresorbable vascular scaffold: Insights from the FRANCE ABSORB registry

BACKGROUND

Randomized trials comparing the first-generation absorb bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, CA, USA) with a drug-eluting stent showed a moderate but significant increase in the rate of 3-year major adverse cardiac events and scaffold thrombosis, followed by a decrease in adverse events after 3 years.

AIM

The objective of this study was to assess the 5-year outcomes of patients treated with at least one absorb BVS and included in the FRANCE ABSORB registry.

METHODS

All patients treated in France with an absorb BVS were prospectively included in a large nationwide multicentre registry. The primary efficacy outcome was the occurrence of 5-year major adverse cardiac events. Secondary efficacy outcomes were the rates of 5-year target vessel revascularization and definite/probable scaffold thrombosis.

RESULTS

Between September 2014 and April 2016, 2,070 patients were included in 86 centres (mean age 55±11 years; 80% men; 49% with acute coronary syndrome). The rates of 1-, 3- and 5-year major adverse cardiac events were 3.9%, 9.4% and 12.1%, respectively (including cardiac death in 2.5% and target vessel revascularization in 10.4%). By multivariable analysis, diabetes, oral anticoagulation, the use of multiple Absorb BVSs and the use of a 2.5mm diameter absorb BVS were associated with 5-year major adverse cardiac events. The rates of 1-, 3- and 5-year definite/probable scaffold thrombosis were 1.5%, 3.1% and 3.6%, respectively. By multivariable analysis, older age, diabetes, anticoagulation at discharge and the use of a 2.5mm diameter absorb BVS were associated with 5-year scaffold thrombosis.

CONCLUSIONS

Absorb BVS implantation was associated with low rates of 1-year major adverse cardiac events, which increased significantly at 3-year follow-up. There was a clear decrease in the rates of scaffold thrombosis and major adverse cardiac events after 3 years.

Lesion impacts on long-term outcomes in patients implanted with bioresorbable vascular scaffold

BACKGROUND

Bioresorbable vascular scaffold (BVS) had been implanted to several kinds of complex coronary lesions in real-world practice. We tested if long-term outcomes of BVS for complex lesions would be worse than that for relatively simple lesions.

METHODS

We analyzed 457 patients (59 ± 12 years, 87% male) with 714 BVS implanted for their 529 lesions and median follow-up of 32.7 (26.8-39.3) months. Complex group (N = 284) was defined as those with BVS for acute coronary syndrome, chronic total occlusion, bifurcation/ostial lesions, instent restenosis/hybrid with metallic stents, diffuse lesions (overlapped by 2 BVS with each ≧ 18 mm), venous graft/left main lesions, or lesions after rotablation. We compared their outcomes with the remaining 173 patients as non-complex group.

RESULTS

The complex group had more chronic kidney disease (7% vs. 2%), multivessel disease (78% vs. 65%), use of intravascular imaging (40% vs. 23%), and more BVS (1.8 ± 0.9 vs. 1.1 ± 0.3) with longer total lengths (47 ± 22 vs. 29 ± 8 mm) implanted than non-complex group (all p < 0.05). However, the long-term target lesion revascularization (TLR) or target lesion failure (TLF) was similar (log rank p > 0.05) between the two groups. Multivariate Cox regression analyses showed BVS for ACC/AHA type C lesions was independently associated with higher risks of TLR (hazard ratio: 2.7, 95% CI = 1.1-6.6) and TLF (hazard ratio: 2.6, 95% CI = 1.1-6.3).

CONCLUSIONS

Comparable outcomes were found between BVS for complex and non-complex lesion category. However, higher risks of TLR and TLF for type C lesions still suggested the prognostic impact of lesion complexity on long-term outcomes of BVS.

Intravascular ultrasound predictors of long-term outcomes following ABSORB bioresorbable scaffold implantation: A pooled analysis of the ABSORB III and ABSORB Japan trials

BACKGROUND

The long-term prognostic impact of IVUS findings following Absorb BVS implantation remains uncertain. This study aimed to identify the IVUS predictors of long-term clinical outcomes following ABSORB bioresorbable vascular scaffold (BVS) implantation from the pooled IVUS substudy cohorts of the ABSORB III and Japan trials.

METHODS

A total of 298 lesions in 286 patients were enrolled with 2:1 randomization to ABSORB BVS vs. cobalt-chromium everolimus-eluting stents. This sub-analysis included 168 lesions of 160 patients in the Absorb arm whose post-procedural quantitative IVUS were available. The primary endpoint of this analysis was device-oriented composite endpoint (DOCE) of target lesion failure, including cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization. The median follow-up duration was 4.9 [3.1-5.0] years.

RESULTS

During follow-up, DOCE occurred in 10.1% of lesions treated with Absorb BVS. Among several post-procedural IVUS indices associated with DOCE, non-uniform device expansion (defined as uniformity index = minimum / maximum device area) (hazard ratio 0.47 per 0.1 increase [95%CI 0.28 to 0.77]; p = 0.003) and residual reference plaque burden (hazard ratio 4.01 per 10% increase [95%CI 1.50 to 10.77]; p = 0.006) were identified as independent predictors of DOCE by Cox multivariable analysis.

CONCLUSIONS

Nonuniform device expansion and substantial untreated residual plaque in reference segments were associated with long-term adverse events following BVS implantation. Baseline imaging to identify the appropriate device landing zone and procedural imaging to achieve uniform device expansion if possible (e.g. through post-dilatation) may improve clinical outcomes of BVS implantation.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01751906 (ABSORB III); NCT01844284 (ABSORB Japan).

Factors associated with long-term major adverse cardiac events of coronary bioresorbable vascular scaffold

The long-term clinical outcomes after implantation of bioresorbable vascular scaffolds (BVS) in a real-world cohort were not well described. To identify factors associated with major adverse cardiovascular events (MACE) on long-term follow-up after implantation of BVS in patients undergoing elective percutaneous coronary intervention (PCI). This was an observational study based on a hospital registry of percutaneous coronary intervention. Participants were consecutive patients who underwent PCI and implanted with at least one everolimus-eluting BVS (Absorb^®) in a single center between 2014 and 2017. Among the 170 cases analyzed (mean age 60.4 ± 10.7), a total of 203 Absorb BVS were implanted. MACE developed in 33 (19.4%) patients over a median follow-up period of 61 months, including 9 (5.3%) deaths, 13 (7.6%) non-fatal myocardial infarction and 19 (11.2%) ischemia driven target vessel revascularization. Definite or probable stent thrombosis developed in 4 (2.4%) patients. In crude analysis, history of smoking and initial presentation of non-ST elevation-acute coronary syndrome (NSTE-ACS) were predictors of long-term MACE. In adjusted analysis, presentation with NSTE-ACS was an independent predictor of long-term MACE [adjusted odds ratio (OR) 4.52; 95% confidence interval (95% CI) 1.50 to 13.6, P = 0.007]. Among patients receiving implantation of ABSORB BVS, presentation with NSTE-ACS was an independent predictor of MACE after a median follow-up period of 61 months. Future research is needed to confirm these findings and to determine the long-term safety of BVS in patients with NSTE-ACS.

Peri-strut low intensity areas and in-scaffold neointima growth after bioresorbable scaffold implantation in STEMI. A serial optical coherence tomography study

BACKGROUND

Peri-strut low intensity areas (PLIA) visualized by optical coherence tomography (OCT) have been related to neointimal proliferation and increased incidence of target lesion revascularization in stable coronary artery disease. The aim of this study was to determine the association between PLIA by OCT and the long-term vascular healing response after bioresorbable scaffold (BRS) implantation in the setting of ST-segment elevation myocardial infarction (STEMI).

METHODS

This is a single-centre, longitudinal, cohort study with a serial: baseline, 1, 2 and 5 years OCT evaluation of neointimal response (lumen area and neoatherosclerosis) after percutaneous coronary intervention (PCI) with BRS Absorb™ 1.0 implantation in patients presenting with STEMI. PLIA was analyzed in every cross section and scored: 0-no PLIA; 1-PLIA < 1 quadrant; 2-PLIA ≥ 1 and <2 quadrants; 3-PLIA ≥ 2 and <3 quadrants; 4-PLIA in ≥3 quadrants.

RESULTS

Of the 23 patients implanted BRS, 18 completed 2-year follow-up, whereas complete OCT data up to 5 years were available in 12 patients. Presence of PLIA was identified in 100% patients at 1 and 2 years, whereas at 5 years neither PLIA nor scaffold struts were visualized by OCT. Neoatherosclerosis was identified in 73,68% patients after 1 year and in all patients at 2 and 5 years. The mean PLIA score > 1 at 2 years was associated with greater percentage of minimum lumen area decrease after 2 years from index procedure.

CONCLUSIONS

The extent of PLIA by OCT at 2 years after primary PCI with BRS was associated with lumen area decrease. Neoatherosclerosis formation was detected in all patients at 2 and 5 years. PLIA assessment could serve as an additive means to predict neointimal healing pattern after next generation BRS implantation.

A case report of a recurrent early and late Bioresorbable vascular scaffold thrombosis: serial angiography and optical coherence tomography findings

Background

In bioresorbable vascular scaffolds (BVSs), there is some concern about a possible increase in the rate of scaffold thromboses (ScTs). Although several characteristics similarly contribute to the development of both early and late ScTs, there are also clearly different pathomechanisms between the two time-dependent types of thromboses, especially with BVSs.

Case presentation

We recently experienced a very rare case of a 69-year-old man who had recurrent early and late ScTs with somewhat differing pathomechanisms as assessed by optical coherence tomography (OCT). For the late ScT, OCT identified a scaffold dismantling in the same place that a peri-strut low intensity area (PLIA) was observed in the previous OCT finding.

Conclusion

We report the management of an ScT in a case with findings such as a heterogeneous a BVS degradation, peri-strut low intensity area (PLIA), intraluminal scaffold dismantling, and under-sizing and/or stent malapposition observed in OCT.

A paradox in sex-specific clinical outcomes after bioresorbable scaffold implantation: 2-year results from the AIDA trial

BACKGROUND

Females are underrepresented in clinical trials evaluating new stent technologies whilst results may differ between the sexes. Females are known to have smaller, more tortuous coronary arteries and have generally more comorbidities. On the other hand, they may have smaller plaque burden. This subgroup-analysis sought to assess sex-specific outcomes after Absorb bioresorbable vascular scaffold (BVS) or XIENCE everolimus-eluting stent (EES) implantation.

METHODS

The AIDA trial was an investigator-initiated, non-inferiority, all-comers trial, in which 1845 patients were randomly assigned to either Absorb BVS or XIENCE EES. Baseline clinical, angiography and procedural variables, as well as 2-year clinical outcomes were analyzed by sex and device modality.

RESULTS

Of the 1845 randomized patients, 475 (25.7%) were females. The 2-year rates of target vessel failure (TVF) with Absorb BVS versus XIENCE EES in females were 6.4% versus 10.6% (HR 0.59; 95% CI: 0.31-1.11; p = 0.10) and in males 12.7% versus 9.7% (HR 1.34; 95% CI: 0.98-1.85; p = 0.07). Males treated with Absorb BVS were at higher risk for TVF compared to females treated with Absorb BVS (HR 2.06; 95% CI 1.21-3.53; p = 0.007). Definite/probable device thrombosis occurred in females with Absorb BVS versus XIENCE EES in 1.6% versus 1.4% (HR 1.15; 95% CI: 0.26-5.12; p = 0.86) and in males 3.9% versus 0.7% (HR 5.55; 95% CI: 2.11-14.35; p < 0.001). A statistical significant interaction between sex and device was present for TVF (p = 0.02), but was not seen for definite/probable device thrombosis (p = 0.08).

CONCLUSIONS

In this subgroup analysis, Absorb BVS used in routine practice tends to result in better clinical outcomes in females compared to males.

Absorb GT1 Bioresorbable Vascular Scaffold System - 1-Year Post-Marketing Surveillance in Japan

BACKGROUND

The Japan post-marketing surveillance (PMS) for the Absorb GT1 bioresorbable vascular scaffold (BVS) mandated an intracoronary imaging-guided implantation technique.Methods and Results:We enrolled 135 patients who were planned to undergo PCI with THE Absorb GT1. Adequate lesion preparation, imaging-guided appropriate sizing, and high-pressure post-dilatation using a noncompliant balloon to minimize final diameter stenosis were recommended. The primary endpoint was the scaffold thrombosis rate at 3 months. All patients successfully received at least 1 Absorb GT1 at the index procedure and completed 1-year follow-up. All 139 lesions were predilatated: cutting/scoring balloon and noncompliant balloon were used in 48 (34.5%) and 58 (41.7%) lesions, respectively. Post-dilatation was performed in 137 (98.5%) lesions with mean high pressure of 18.8 atm. Optical coherence tomography (OCT) was used in 127 of 139 (91.4%) lesions, and revealed 56.7% of lesions had incomplete scaffold apposition (ISA) but only in 1.89% in the per strut analysis. All patients received adenosine diphosphate receptor antagonist at discharge, and 132 (97.8%) patients continued therapy through the year. No definite/probable scaffold thrombosis, cardiac death, myocardial infarction, or ischemia-driven target lesion revascularization was reported up to 1 year follow-up.

CONCLUSIONS

Appropriate OCT-guided BVS implantation may prevent incomplete strut apposition, thereby reducing the risk of target lesion failure and scaffold thrombosis.

Neoatherosclerosis - Long-Term Assessment of Bioresorbable Vascular Scaffold

Although metallic stents improved the safety and efficacy of percutaneous coronary intervention (PCI), even the latest generation of drug-eluting stents (DES) is still limited by several factors. The limitations of DES are mainly related to the permanent metallic caging in vessel, chronic inflammatory response to the polymer and adverse effects of antiproliferative drug on endothelial tissue, leading to impaired physiological vasomotor response and late stent-related adverse events such as stent thrombosis and neoatherosclerosis. Bioresorbable vascular scaffold (Absorb BVS; Abbott Vascular) was designed to overcome these drawbacks of DES by disappearing from the vessel wall. Absorb BVS, however, was withdrawn from the world market because of increased incidence of scaffold thrombosis compared with DES. Importantly, only very limited long-term post-BVS implantation data are available, especially with regard to neoatherosclerosis, which can lead to very late adverse events even after resorption of the scaffold. Therefore, the goal of this review was to highlight the mid to long term clinical outcomes published to date, and to describe the features of the intimal healing process and neoatherosclerosis in the 5 years following Absorb BVS implantation, mainly based on our previous study. This may provide important information on the pathophysiology of the scaffolded vessel for clinicians, and promote identification of future bioresorbable materials for PCI that will minimize the stimulus for neoatherosclerosis.

Guided de-escalation of DAPT in acute coronary syndrome patients undergoing percutaneous coronary intervention with BVS implantation: a post-hoc analysis from the randomized TROPICAL-ACS trial

To investigate the safety and efficacy of an early platelet function testing (PFT)-guided de-escalation of dual antiplatelet treatment (DAPT) in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) with bioresorbable vascular scaffolds (BVS). Early DAPT de-escalation is a new non-inferior alternative to 12-months DAPT in patients with biomarker positive ACS treated with stent implantation. In this post-hoc analysis of the TROPICAL-ACS trial, which randomized 2610 ACS patients to a PFT-guided DAPT de-escalation (switch from prasugrel to clopidogrel) or to control group (uniform prasugrel), we compared clinical outcomes of patients (n = 151) who received a BVS during the index PCI. The frequency of the primary endpoint (cardiovascular death, myocardial infarction, stroke or BARC ≥ 2 bleeding) was 8.8% (n = 6) in the de-escalation group vs. 12.0% (n = 10) in the control group (HR 0.72, 95% CI 0.26–1.98, p = 0.52) at 12 months. One early definite stent thrombosis (ST) occurred in the control group (day 19) and 1 possible ST (sudden cardiovascular death) in the de-escalation group (day 86), both despite prasugrel treatment and in a background of high on-treatment platelet reactivity assessed at day 14 after randomization (ADP-induced platelet aggregation values of 108 U and 59 U, respectively). A PFT-guided DAPT de-escalation strategy could potentially be a safe and effective strategy in ACS patients with BVS implantation but the level of platelet inhibition may be of particular importance. This hypothesis-generating post-hoc analysis requires verification in larger studies with upcoming BVS platforms.

Bioresorbable vascular scaffolds for percutaneous treatment of chronic total coronary occlusions: a meta-analysis

BACKGROUND

BRS represent a new approach to treating coronary artery disease. Beneficial properties of BRS regarding the restoration of vasomotility after resorption make them attractive devices in CTO revascularization. However, experience in this setting is limited.

METHODS

We systematically searched Medline, Scholar, and Scopus for reports of at least 9 patients with CTO undergoing BRS implantation. Patients' and procedural characteristics were summarized. The primary outcome of interest was target lesion revascularization (TLR). Pooled estimates were calculated using a random-effects meta-analysis. The study protocol was registered in PROSPERO (CRD42017069322).

RESULTS

Thirteen reports for a total of 843 lesions with a median follow-up of 12 months (IQR 6-12) were included in the analysis. At short-term, the summary estimate rate of TLR was 2.6% (95% CI: 1 to 4%, I² = 0%, P = 0.887) while at mid to long-term it was 3.8% (95% CI: 2 to 6%, I² = 0%, P = 0.803). At long-term follow-up (≥12 months), the summary estimate rate of cardiac death was 1.1% (95% CI: 0 to 2%, I² = 0%, P = 0.887). The summary estimate rates of scaffold thrombosis and clinical restenosis were respectively 0.9% (95% CI: 0 to 2%, I² = 0%, P = 0.919) and 1.8% (95% CI: 0 to 4%, I² = 0%, P = 0.448). Finally, the summary estimate rate of target vessel revascularization was 6.6% (95% CI: 0 to 11%, I² = 0%, P = 0.04).

CONCLUSIONS

Implantation of BRS in a population with CTO is feasible, although further longer-term outcome studies are necessary.

Pharmacokinetic Study of Sirolimus-Eluting BioResorbable Vascular Scaffold System for Treatment of De Novo Native Coronary Lesions: A Sub-Study of MeRes-1 Trial

Background

MeRes100™ (Meril Life Sciences Pvt. Ltd., Vapi, India) is a novel sirolimus-eluting bioresorbable vascular scaffold (BRS). The purpose of this sub-study of MeRes-1 trial is to evaluate the systemic release of sirolimus from MeRes100 BRS implanted for the treatment of de novo native coronary artery lesions.

Methods

The MeRes-1 is a prospective, multicenter, first-in-human trial of sirolimus-eluting MeRes100 BRS. The pharmacokinetic sub-study was conducted at two Indian sites in 10 patients who were implanted with the MeRes100 BRS loaded with sirolimus at a dose of 1.25 µg/mm². Venous blood samples were collected at pre-dose and 12-time points after implantation of the scaffold. Sirolimus concentration was successively analyzed using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry method.

Results

A total of 12 scaffolds were implanted in 10 patients. Non-compartmental analysis demonstrated time to reach peak concentration of sirolimus between 0.5 h to 3 h after scaffold implantation. The peak concentration (C_max) was deduced to be 7.47 ± 2.61 ng/mL, AUC was 436.45 ± 171.24 h·ng/mL, and the t_½ was observed at 98.59 ± 33.58 h. The clearance was 0.66 ± 0.16 L/h and lower limit of quantification was detectable at 14.1 days.

Conclusions

The MeRes-1 pharmacokinetic sub-study confirmed that MeRes100 BRS is safe and tolerable at limited systemic exposure of sirolimus.

Immune-inflammatory response after bioresorbable vascular scaffold implantation in patients with acute myocardial infarction with ST elevation in a long-term perspective

A higher rate of bioresorbable vascular scaffold (BVS) thrombosis has been observed after device implantation compared to implantation of permanent metallic stents in recently published studies. The mechanism of BVS thrombosis is currently under debate. To assess whether the immune-inflammatory response after BVS implantation is a potential trigger of BVS thrombosis. The PRAGUE-19 study was an academic study that enrolled consecutive patients with ST-segment elevation myocardial infarction (STEMI) with the intention to implant a BVS. A laboratory sub-study included 49 patients with an implanted BVS (of which 38 underwent the complete 2-year follow-up) and 52 patients having an implanted permanent metallic stent as the control group (of which 30 underwent the complete 2-year follow-up). Samples for inflammatory markers [high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α)] were taken before BVS or stent implantation, on days 1 and 2 after device implantation and at 1 month and 2 years for a clinical control. The primary combined clinical endpoint of the sub-study (death, reinfarction or target vessel revascularization) occurred in 4.08% of the BVS group and 7.69% of the control group (p = 0.442) during the 2-year follow-up period, with overall mortality of 2.04% in the BVS group and 1.92% in the control group (p = 0.966). Definite BVS thrombosis occurred in one patient in the subacute phase; there was no late or very late thrombosis. Two definite stent thromboses were observed in the control group: one in the subacute phase and the other in the late phase. Baseline inflammatory marker levels did not differ between the groups. Lower levels of IL-6 and hs-CRP were observed in the BVS group compared to the control group (12.02 ± 5.94 vs. 15.21 ± 5.33 pg/ml; p < 0.01; 3952.9 ± 1704.75 ng/ml vs. 4507.49 ± 1190.01 ng/ml; p = 0.037, respectively) on days 1 and 2 (12.01 ± 6.31 vs. 13.85 ± 6.01 pg/ml; p = 0.089; 4447.92 ± 1325.31 ng/ml vs. 4637.03 ± 1290.99 ng/ml; p = 0.255, respectively). No differences in IL-6 or hs-CRP were observed after 1 month or 2 years in the clinical control. Levels of TNF-α did not differ between the groups in the early period after BVS or metallic stent implantation, nor during follow-up. The immune-inflammatory response is lower during the early phase after BVS implantation compared to that after metallic stent implantation, but the responses did not differ in the long term.

Different behaviors of bioresorbable vascular scaffold in different types of calcified lesion: Insights from intravascular imaging

A 55-year-old male underwent percutaneous coronary intervention (PCI) for left anterior descending artery chronic total occlusion. After lesion preparation with non-compliant (NC) balloon, two bioresorbable vascular scaffolds (2.5/28 mm, 3.0/28 mm, Absorb BVS, Abbott Vascular, Santa Clara, CA, USA) were implanted followed by 1:1 sized NC balloon post-dilatation at 20 atm. Final intravascular ultrasound (IVUS) showed acceptable BVS expansion in diffusely calcified lesions. Twenty-one months' follow-up coronary angiography revealed severe restenosis with reocclusion at the distal edge of the distal BVS. After recanalization with a 1.0 mm balloon, optical coherence tomography (OCT) was performed. Quantitative analysis comparing OCT and IVUS at the index procedure demonstrated that minimum scaffold area at follow-up became significantly smaller and with higher eccentricity, suggesting severe recoil at the lesions with thick calcium spot, whereas these changes were not observed at the lesion with relatively thin calcification. The lesions were successfully revascularized with drug-eluting stents and final OCT showed symmetric expansion of metallic stents. Our case demonstrates that different types of calcification can have an impact on BVS expansion and recoil. In calcified lesions, an optimal implantation technique is mandatory to achieve the best possible results, and characterization of calcified lesions with intravascular imaging may be helpful to decide PCI strategy with BVS. <Learning objective: Calcified lesions represent a challenging lesion subset for bioresorbable vascular scaffold (BVS) because of less radial strength of the latter. Quantitative analysis with intravascular imaging demonstrated that different types of calcification can have an impact on BVS expansion and recoil. In calcified lesions, an optimal implantation technique is mandatory to achieve the best possible results, and characterization of calcified lesions with intravascular imaging may be helpful to decide percutaneous coronary intervention strategy with BVS.>.

Three-year follow-up optical coherence tomography of under-expanded drug-eluting stent in-stent restenosis treated with ABSORB bioresorbable vascular scaffold following ultra-high pressure pre-dilatation

The management of in-stent restenosis continues to be a common challenge in modern interventional cardiology. Drug-eluting stents have emerged to be an effective treatment following bare-metal stent in-stent restenosis as compared with drug-coated balloon angioplasty and repeat bare-metal stenting. The addition of another metallic layer is however undesirable and may limit further treatment options. In the last few years, everolimus-eluting bioresorbable vascular scaffolds have become available in treating native coronary artery disease with complete hydrolysis into water and carbon dioxide within 3-5 years. To exploit this property, we successfully used it to manage a case of drug-eluting stent in-stent restenosis from a previously under-expanded stent as demonstrated in this case. Small registry series have also recently been published supporting favorable outcomes with this approach. To the best of our knowledge, this case has the longest optical coherence tomography follow-up beyond 3 years. <Learning objective: The dedicated dual-layer OPN NC balloon (Schwager Medica, Winterthur, Switzerland) could be used in the under-expanded metallic stent that is not overcome by conventional non-compliant balloons as demonstrated in our case. The application of bioresorbable vascular scaffold in drug-eluting stent in-stent restenosis has satisfactory medium- to long-term clinical outcome. The 3-year follow-up intracoronary study demonstrated complete tissue coverage of the scaffold. Complete bioresorption of the scaffold, by hydrolysis into carbon dioxide and water, takes approximately 3-5 years, thus avoiding another layer of metallic cage.>.

A randomized trial comparing two stent sizing strategies in coronary bifurcation treatment with bioresorbable vascular scaffolds - The Absorb Bifurcation Coronary (ABC) trial

BACKGROUND

Limited information is available on the use of Bioresorbable Vascular Scaffold (BVS) in bifurcations involving significant side branches. When treating bifurcation disease with metal stents, the recommendation is to choose a stent diameter based on the distal main vessel diameter. Whether this sizing strategy is applicable to BVS is currently unknown.

METHODS

We randomised 37 patients undergoing elective PCI for 'false' bifurcation disease (Medina 0,1,0; 1,0,0; 1,1,0) to receive BVS based either on proximal or distal reference diameters. Optical Frequency Domain Imaging (OFDI) measurements were performed pre BVS insertion to obtain proximal and distal reference diameters and post implantation. BVS size was chosen according to the proximal or distal reference diameter as per randomisation. Implantation was performed using the PSP technique tailored to bifurcation stenting. OFDI was repeated post implantation to confirm satisfactory expansion and apposition.

RESULTS

Baseline demographics between the two groups were similar. Patients were aged 62.8 ± 3.3 years; 76% were male. Mean side branch diameter was 2.24 ± 0.13 mm. TIMI III flow in the main vessel was achieved in all cases. Side branch occlusion occurred in 1 case (2.7%). In the distal-sizing arm, there was a greater incidence of significant malapposition (>300 μm) at the proximal end of the scaffold on OCT (2.3% versus 0.8%, p 0.023). The incidence of distal edge dissections was numerically greater in the proximal-sizing group but this was not statistically significant (31.3% vs 11.8%, p 0.17).

CONCLUSION

Both proximal and distal sizing strategies have similar procedural complication rates when using the ABSORB BVS to treat coronary bifurcations. However a proximal sizing strategy is associated with less malapposition and may be preferable.

Clinical outcomes of bioresorbable vascular scaffold to treat all-comer patients. Are patients with acute coronary syndrome better candidates for bioresorbable vascular scaffold?

BACKGROUND

Scaffold thromboses (ST) and adverse events and have been associated with bioresorbable vascular scaffolds (BVS) at long-term, but their mechanism remains unclear. We sought to evaluate patient and lesion characteristics associated with mid- to long-term outcomes in patients treated with BVS.

METHODS

This is an observational single-center, single-arm, retrospective study evaluating the performance of BVS in an all-comer population, including complex lesions (chronic total occlusions, long lesions), small vessels, and acute coronary syndromes (ACS).

RESULTS

From May 2013 to June 2015, we included 482 patients (580 lesions) that were treated with BVS implantation including 71.2% treated for ACS in the present analysis. Mean follow-up period was 816.2 ± 242.6 days. The primary endpoint was device oriented cardiac events (DOCE), defined as a composite of target-lesion revascularization (TLR), ST, target vessel myocardial infarction (TVMI) and cardiac death. Using Kaplan-Meier methods, the DOCE and ST rates at 36 months were 9.4% and 2.3%, respectively. No ST occurred between 2 and 3 years and ST occurred after 3 years, in one patient. Using multivariate analysis, ACS was the only significant predictor of lower rates of DOCE (p = 0.04, HR: 0.47, 95% CI: 0.23-0.96).

CONCLUSIONS

In this large all-comers real-world cohort, lesions treated with BVS had non-negligible rates of DOCE and ST, in line with previous published randomized trials. The occurrence of very late event was very low after 24 months. ACS patients had lower rates of DOCE.

Low major adverse cardiac event rates following bioresorbable vascular scaffold implantation: Impact of implantation technique on treatment outcomes

Background and objective

Studies conducted across the world have reported that the rates of major adverse cardiac events (MACE) following the use of bioresorbable vascular scaffolds (BVS) are comparable to that noted with traditional drug eluting stents (DES). However, there is limited data on the immediate and medium-term clinical outcomes following the use of the Absorb BVS (Abbott Vascular, Santa Clara, SA) in the Indian context. This study was conducted to determine real-world evidence on the immediate and medium-term clinical outcomes in all patients undergoing percutaneous coronary intervention (PCI) with the Absorb BVS.

Methods

Data of all patients who were treated with Absorb BVS at our center were evaluated. Between December 2012 and October 2016, 142 patients underwent PCI with BVS. The MACE rates during hospitalization, at 30 days, 3 months, 6 months after PCI, and every 6 months thereafter were the primary endpoints evaluated with median follow up of 13 months.

Results

Mean age of the study participants was 53.7 ± 11.8 years. Intravascular ultrasound imaging was performed in 15.34% of patients. Predilatation and postdilatation were performed in 81.8% and 84.6% of scaffolds, respectively. There were no episodes of MACE during hospitalization. However, 1 BVS-related MACE was observed at the 1-month (0.7%) as well as at the ≥12 month (0.8%) follow up visits. At the 6- and 12-month follow up visits, 2 (1.5%) and 3 (2.5%) non-BVS-related MACEs, respectively, were recorded.

Conclusion

The use of Absorb BVS in this real-world experience was associated with very good immediate and medium-term clinical outcomes.

Vascular response and healing profile of everolimus-eluting bioresorbable vascular scaffolds for percutaneous treatment of chronic total coronary occlusions: A one-year optical coherence tomography analysis from the GHOST-CTO registry

BACKGROUND

Bioresorbable vascular scaffolds (BVS) have been heralded with potential benefits that are especially desired in long lesions, including chronic total occlusions (CTOs). Procedural feasibility and mid-term outcomes of BVS in CTOs have been reported. However, there is still a paucity of data regarding the vascular and healing response to BVS in CTOs evaluated by optical coherence tomography (OCT).

METHODS

This study included prospectively 21 patients who had a CTO lesion treated with a BVS. Angiography and OCT scan were recorded at either post-implantation and 1-year follow-up. Quantitative coronary angiography and OCT analyses were performed by an independent core laboratory.

RESULTS

The angiographic analysis showed a significant increase in the percentage of in-segment diameter stenosis at 1year (11.89±9.5% vs. 21.84±11.7%; p=0.002). The OCT analysis showed a trend (p=0.07) towards increased mean scaffold area and significant reductions in mean lumen diameter (3.1±0.36mm vs. 2.85±0.47mm; p=0.0046), mean lumen area (7.8±1.73mm² vs. 6.76±2mm²; p=0.0082) and minimal lumen area (5.26±1.86mm² vs. 3.56±1.52mm²; p<0.0001). Malapposition area and volume decreased from 0.26±0.17mm² to 0.08±0.1mm² (p=0.0003) and from 14.17±12.92mm³ to 3.99±4.46mm³ (p=0.0014), respectively. The rate of uncovered or malapposed struts, measured at the frame level, was 5.29±6.48% at 1year.

CONCLUSIONS

In a small series of CTO patients treated with BVS implantation, OCT outcomes at 1year displayed an overall favorable vascular response and healing profile.

Coronary calcification as a mechanism of plaque/media shrinkage in vessels treated with bioresorbable vascular scaffold: A multimodality intracoronary imaging study

BACKGROUND AND AIMS

Whether coronary calcification is correlated with plaque/media shrinkage (PS) remains unclear. The aim of this study was to assess the relationship between the calcification process and PS, combining serial optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in vessels treated with bioresorbable vascular scaffolds (BVS).

METHODS

In 15 patients (16 vessels), OCT and IVUS images were matched using anatomic landmarks at post-procedure and five years. PS was defined as relative decrease in plaque/media area >5%. The association between the calcification process and PS was investigated. Mixed effect models were used to assess correlations and changes over time.

RESULTS

Seventy-two OCT and IVUS paired cross sections in- and out-scaffolded segments were matched at baseline and follow-up (432 images). In total, 35 out of the 72 cross sections showed PS, and 37 cross sections showed no PS (non-PS) at 5-year follow-up. Delta (Δ) plaque/media area showed negative correlation with Δ OCT calcium area (r = -0.29, p = 0.004), Δ OCT calcium arc (r = -0.42, p < 0.001), Δ OCT calcium length (r = -0.5, p < 0.001), and Δ IVUS calcium arc (r = -0.31, p = 0.024), respectively. On echogenicity analysis, Δ plaque/media area was positively associated with Δ hypoechogenic area (r = 0.47, p = 0.002). An increase in calcium area was negatively correlated to Δ hypoechogenicity (r = -0.29, p < 0.016). The increase in calcium area was positively correlated with Δ lumen area (r = 0.24, p = 0.044).

CONCLUSIONS

In segments treated with BVS, the calcification process was associated with PS, decrease in the hypoechogenic tissue and late luminal enlargement. Combining IVUS and OCT provides a unique method to assess the correlation between the calcification process and plaque/media shrinkage.

Bioresorbable Vascular Scaffold Korean Expert Panel Report

Bioresorbable vascular scaffold (BRS) is an innovative device that provides structural support and drug release to prevent early recoil or restenosis, and then degrades into nontoxic compounds to avoid late complications related with metallic drug-eluting stents (DESs). BRS has several putative advantages. However, recent randomized trials and registry studies raised clinical concerns about the safety and efficacy of first generation BRS. In addition, the general guidance for the optimal practice with BRS has not been suggested due to limited long-term clinical data in Korea. To address the safety and efficacy of BRS, we reviewed the clinical evidence of BRS implantation, and suggested the appropriate criteria for patient and lesion selection, scaffold implantation technique, and management.

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.

The effect of bioresorbable vascular scaffold implantation on distal coronary endothelial function in dyslipidemic swine with and without diabetes

BACKGROUND

We studied the effect of bioresorbable vascular scaffold (BVS) implantation on distal coronary endothelial function, in swine on a high fat diet without (HFD) or with diabetes (DM+HFD).

METHODS

Five DM+HFD and five HFD swine underwent BVS implantation on top of coronary plaques, and were studied six months later. Conduit artery segments >5mm proximal and distal to the scaffold and corresponding segments of non-scaffolded coronary arteries, and segments of small arteries within the flow-territory of scaffolded and non-scaffolded arteries were harvested for in vitro vasoreactivity studies.

RESULTS

Conduit segments proximal and distal of the BVS edges showed reduced endothelium-dependent vasodilation as compared to control vessels (p≤0.01), with distal segments being most prominently affected(p≤0.01). Endothelial dysfunction was only observed in DM±HFD swine and was principally due to a loss of NO. Endothelium-independent vasodilation and vasoconstriction were unaffected. Surprisingly, segments from the microcirculation distal to the BVS showed enhanced endothelium-dependent vasodilation (p<0.01), whereas endothelium-independent vasodilation and vasoconstriction were unaltered. This enhanced vasorelaxation was only observed in DM+HFD swine, and did not appear to be either NO- or EDHF-mediated.

CONCLUSIONS

Six months of BVS implantation in DM+HFD swine causes NO-mediated endothelial dysfunction in nearby coronary segments, which is accompanied by a, possibly compensatory, increase in endothelial function of the distal microcirculation. Endothelial dysfunction extending into coronary conduit segments beyond the implantation-site, is in agreement with recent reports expressing concern for late scaffold thrombosis and of early BVS failure in diabetic patients.

Recommendations for the use of bioresorbable vascular scaffolds in percutaneous coronary interventions : 2017 revision

BACKGROUND

To eliminate some of the potential late limitations of permanent metallic stents, the bioresorbable coronary stents or 'bioresorbable vascular scaffolds' (BVS) have been developed.

METHODS

We reviewed all currently available clinical data on BVS implantation.

RESULTS

Since the 2015 position statement on the appropriateness of BVS in percutaneous coronary interventions, several large randomised trials have been presented. These have demonstrated that achieving adequate 1 and 2 year outcomes with these first-generation BVS is not straightforward. These first adequately powered studies in non-complex lesions showed worse results if standard implantation techniques were used for these relatively thick scaffolds. Post-hoc analyses hypothesise that outcomes similar to current drug-eluting stents are still possible if aggressive lesion preparation, adequate sizing and high-pressure postdilatation are implemented rigorously. As long as this has not been confirmed in prospective studies the usage should be restricted to experienced centres with continuous outcome monitoring. For more complex lesions, results are even more disappointing and usage should be discouraged. When developed, newer generation scaffolds with thinner struts or faster resorption rates are expected to improve outcomes. In the meantime prolonged dual antiplatelet therapy (DAPT, beyond one year) is recommended in an individualised approach for patients treated with current generation BVS.

CONCLUSION

The new 2017 recommendations downgrade and limit the use of the current BVS to experienced centres within dedicated registries using the updated implantation protocol and advise the prolonged usage of DAPT. In line with these recommendations the manufacturer does not supply devices to the hospitals without such registries in place.

Mid-term and long-term safety and efficacy of bioresorbable vascular scaffolds versus metallic everolimus-eluting stents in coronary artery disease: A weighted meta-analysis of seven randomised controlled trials including 5577 patients

Aims

Mid- and long-term safety and efficacy of the Absorb bioresorbable vascular scaffold (BVS) have been studied in randomised trials; however, most were not individually powered for clinical endpoints. We performed a weighted meta-analysis comparing mid- and long-term outcomes in patients treated with the BVS compared with the Xience metallic stent.

Methods and results

Randomised trials comparing the BVS and Xience were identified by searching MEDLINE, EMBASE and conference abstracts. Seven trials were included (BVS n = 3258, Xience n = 2319) with follow-up between 1–3 years. The primary outcome of target lesion failure occurred more frequently in BVS compared with Xience [OR 1.34; 95% CI 1.11–1.62, p = 0.003]. Overall definite or probable device thrombosis occurred more frequently with the BVS [OR 2.86; 95% CI 1.88–4.36, p < 0.001] and this extended beyond 1 year of follow-up [OR 4.13; 95% CI 1.99–8.57, p < 0.001]. Clinically indicated or ischaemia driven target lesion revascularisation [OR 1.43; 95% CI 1.11–1.83, p = 0.005] and myocardial infarction (all MI) [OR 1.64; 95% CI 1.20–2.23, p = 0.002] were more frequently seen in the BVS compared with Xience. Rates of target vessel failure [OR 1.15; 95% CI 0.91–1.46, p = 0.25] and cardiac death [OR 0.91; 95% CI 0.57–1.46, p = 0.71] were not significantly different between BVS and Xience.

Conclusion

This meta-analysis shows a higher rate of target lesion failure and an almost threefold higher rate of device thrombosis in BVS compared with Xience, which extends beyond the first year. Device thrombosis did not lead to an overall increased (cardiac) mortality.

Electronic supplementary material

The online version of this article (doi: 10.1007/s12471-017-1008-x) contains supplementary material, which is available to authorized users.

Long-term outcome of bioresorbable vascular scaffolds for the treatment of coronary artery disease: a meta-analysis of RCTs

BACKGROUND

Coronary bioresorbable scaffolds (BRS) were developed to overcome the limitations of standard metallic stents, especially to address late events after percutaneous coronary interventions. The aim of this meta-analysis was to evaluate the efficacy and safety of BRS, compared with Everolimus-eluting stents (EES), using the data available from randomized trials, with a focus on long-term outcomes.

METHODS

Published randomized trials comparing BRS to EES for the treatment of coronary artery disease were searched for within PubMed, Cochrane Library and Scopus electronic databases up to April 4th 2017. The summary measure used was odds ratio (OR) with 95% confidence intervals.

RESULTS

A total of 5 studies were eligible, including 5219 patients. At 2 years, BRS was associated with higher rates of target lesion failure (9.4% vs 7.2%; OR = 1.33; 95% CI 1.07 to 1.63; p = 0.008) and device thrombosis (2.3% vs 0.7%; OR = 3.22; 95% CI 1.86 to 5.57; p < 0.0001) compared with EES. The incidence of both early (within 30 days after implantation, 1.1% vs 0.5%, OR 1.97, 95% CI 1.02 to 3.81; p = 0.05) and very-late device thrombosis (>1 year, 0.6% vs 0.1%, OR 4.03, 95% CI 1.37 to 11.82; p = 0.01) was higher with BRS compared with EES.

CONCLUSIONS

BRS may be associated with worse two-years clinical outcomes compared with EES in patients with coronary artery disease.

Comparison of everolimus- and biolimus-eluting coronary stents with everolimus-eluting bioresorbable vascular scaffolds: Two-year clinical outcomes of the EVERBIO II trial

BACKGROUND

Data from randomized controlled trials have shown that the ABSORB BVS is non-inferior to Cobalt Chromium everolimus-eluting stents at 2years.

METHODS & RESULTS

The EVERBIO II trial (Comparison of Everolimus- and Biolimus-Eluting Coronary Stents with Everolimus-Eluting Bioresorbable Vascular Scaffold) is a single-center, assessor-blind, randomized controlled trial enrolling 240 patients with an allocation ration of 1:1:1 conducted at University and Hospital Fribourg, Switzerland. The studied devices were an everolimus-eluting persistent polymer stent (EES), a biolimus-eluting stent with bioabsorbable polymer (BES) and a fully bioresorbable vascular scaffold (BVS). Clinical end points collected at 9months, 12months, and 2years, were academic research consortium defined composites, device thrombosis and target-vessel revascularization. Clinical follow-up at 2years was available in 96% (N=77) of patients in the EES group, in 100% (N=80) in the BES and 99% (N=77) in the BVS group. The device-oriented composite end point of cardiac death, target-vessel myocardial infarction and target-lesion revascularization occurred in 13 (16%) patients treated with EES, in 7 (9%) patients treated with BES and in 16 (21%) patients treated with BVS. There was no significant difference when the metallic stents were compared to the BVS (p=0.12). There was one late scaffold thrombosis throughout the trial in the BVS group, and no definite stent thrombosis in either EES or BES treated patients.

CONCLUSIONS

The current analysis shows no significant differences with regard to clinical outcomes at 2years between BVS and the best-in-class metallic DES. Event rates were numerically higher in BVS-treated patients. However, when BVS were compared to BES alone, the occurrence of device related adverse events was significantly increased.

Mid- to long-term outcome of patients treated with everolimus-eluting bioresorbable vascular scaffolds: Data of the BVS registry Göttingen predominantly from ACS patients

BACKGROUND

Bioresorbable vascular scaffolds (BVS) are widely used in routine clinical practice. While previous studies reported acceptable short- to midterm outcome after BVS implantation, data on longer-term outcome are rare.

METHODS

Patients treated with at least one Absorb®-BVS were consecutively enrolled. Follow-up data were assessed after 834.0 [769.0-1026.0] days. The primary device-oriented composite endpoint (DOCE) was defined as cardiovascular death, myocardial infarction (MI) and/or target lesion revascularization (TLR).

RESULTS

Between 2012 and 2014, 195 patients were included into study analysis. Overall, 244 BVS were implanted. Mean patient age was 64.0[54.3-74.0] years. Three-quarter of patients had an ACS; of those 42.9% had ST-elevation-MI and 40.8% had non-ST-elevation-MI. DOCE occurred in 3.1%, 6.7%, 11.8% and 15.4% of patients during hospital stay, within 6-months, 18-months or during the complete follow-up period, respectively. In those patients, median time until DOCE was 211.5[43.25-567.25] days. In 11 (36.7%) patients DOCE occurred after >12months. Using univariable analysis, bifurcation stenting was associated with a hazard ratio (HR) of 11.8[2.38-58.57] for TLR (p=0.002) and 2.1[1.02-4.49] for DOCE (p=0.045). Similarly, in ACS patients, bifurcation stenting was associated with an increased risk for TLR (HR=10.4[2.01-53.56]; p=0.005) and for DOCE (HR=2.4[1.09-5.32]; p=0.029) and in multivariable analysis, it remained an independent predictor of DOCE (HR=3.0; p=0.018).

CONCLUSIONS

Although, the rates of (potentially) device-related complications following BVS implantation are acceptable, they are nonetheless not negligible. Interestingly, they did not decline over time. Bifurcation stenting could be found as relevant procedure-related predictor of DOCE, especially in ACS patients. Randomized trials are warranted to confirm these findings.

Left Main coronary angioplasty of a 9-year-old child with bioresorbable vascular scaffold [corrected]

Familial hypercholesterolemia is an autosomal dominant disorder due to mutations in the low-density lipoprotein receptor gene, characterized by skin and tendon xanthomas, xanthelasmas, and increased risk of premature coronary artery disease. Here, we report a case of 9-year-old girl who presented with angina and dyspnoea on exertion with xanthomas and an elevated serum cholesterol and triglyceride. She had severe stenosis of the left main coronary artery (LMCA) requiring angioplasty and placement of Bioresorbable vascular scaffold (BVS). This is the first case report in literature of the use of BVS for LMCA stenosis in a 9-year-old child. © 2017 Wiley Periodicals, Inc.

Bioresorbable vascular scaffold to treat malignant in-stent restenosis in a patient with nickel allergy

Nickel is the most frequent allergen in patients with allergic contact dermatitis and nickel allergy has been associated with recurrent in-stent restenosis. However, it is often misdiagnosed because of a low suspicion threshold. It should be discarded in patients with recurrent in-stent restenosis, especially if their medical history reveals prior contact dermatitis. It is also noteworthy and rarely specified that even newer generation stents that use novel metal alloys also contain low amounts of nickel. To avoid the implantation of new stents containing this metal, when percutaneous coronary intervention is indicated, drug eluting balloons or bioresorbable vascular scaffolds associated with small doses of steroids could provide good alternatives of treatment. To the best of our knowledge, this is the first description of this therapeutic alternative in such an exceedingly rare clinical scenario.

Comparative assessment of "plaque/media" change on three modalities of IVUS immediately after implantation of either everolimus-eluting bioresorbable vascular scaffold or everolimus-eluting metallic stent in Absorb II study

The purpose of the study to assess the comparability of immediate changes in plaque/media volume (PV) on three modalities of intravascular ultrasound (IVUS) after implantation of either bioresorbable vascular scaffold (BVS) or everolimus-eluting metallic stent (EES) in Absorb II Study. The two devices have different device volume and ultrasound backscattering that may interfere with the “plaque/media” assessed by three modalities on IVUS: grayscale, backscattering of radiofrequency and brightness function. In a multicenter randomized controlled trial, 501 patients with stable or unstable angina underwent documentary IVUS pre- and post- implantation. The change in plaque/media volume (PV) was categorized into three groups according to the relative PV change in device segment: PV “increased” >+5% (PVI), PV unchanged ±5% (PVU), and PV decreased <−5% (PVD). The change in PV was re-evaluated three times: after subtraction of theoretical device volume, after analysis of echogenicity based on brightness function. In 449 patients, 483 lesions were analyzed pre- and post-implantation. “PVI” was more frequently observed in BVS (53.8%) than EES group (39.4%), p = 0.006. After subtraction of the theoretical device volume, the frequency of “PVI” decreased in both BVS (36.2%) and EES (32.1%) groups and became comparable (p = 0.581). In addition, the percentage of “PVI” was further reduced in both device groups after correction for either radiofrequency backscattering (BVS 34.4% vs. EES 22.6%) or echogenicity (BVS 25.2% vs. EES 9.7%). PV change in device segment was differently affected by BVS and EES devices implantation due to their differences in device volume and ultrasound backscattering. It implies that the lumen volume was also artifactually affected by the type of device implanted. Comparative IVUS assessment of lumen and plaque/media volume changes following implantation of BVS and EES requires specific methodological adjustment.

Is bioresorbable vascular scaffold acute recoil affected by baseline renal function and scaffold selection?

OBJECTIVE

The aim of the present study was to investigate the relationship between glomerular filtration rate (GFR) and acute post-scaffold recoil (PSR) in patients undergoing bioresorbable scaffold (BVS) implantation.

METHODS

We included 130 patients who underwent everolimus-eluting BVS device (Absorb BVS; Abbott Vascular, Santa Clara, CA, USA) or the novolimus-eluting BVS device (Elixir Medical Corporation) implantations for single or multi-vessel disease. Clinical, angiographic variables and procedural characteristics were defined and pre-procedural GFR was calculated for each patient. Post-procedural angiographic parameters of each patient were analyzed. Primary objective of the study was to evaluate the effect of GFR on angiographic outcomes after BVS implantation while secondary objective was to compare post-procedural angiographic results between the two BVS device groups.

RESULTS

Baseline clinical characteristics and angiographic parameters were similar between the two BVS groups. Post-procedural angiographic analysis revealed significantly lower PSR in the DESolve group than the Absorb group (0.10±0.04 vs. 0.13±0.05, p: 0.003). When PSR in the whole study population was evaluated, it was positively correlated with age, tortuosity , calcification and PBR as there was a negative correlation between GFR. Besides GFR were found to be independent predictors for PSR in all groups and the whole study population.

CONCLUSION

In patients undergoing BVS implantation, pre-procedural low GFR is associated with increased post-procedural PSR. Calcification, age, PBR, dyslipidemia and tortuosity are other independent risk factors for PSR. DESolve has lower PSR when compared with Absorb.

Current practices of Asia-Pacific cardiologists in the utilization of bioresorbable scaffolds

BACKGROUND & AIMS

Although Absorb Bioresorbable Vascular Scaffolds (A-BVS) are routinely used in the Asia-Pacific, there is little information on patient selection or deployment technique here. This document investigates the experiences of leading interventional cardiologists from the Asia-Pacific region with a focus on patient characteristics, deployment techniques and management.

METHODS AND RESULTS

A detailed questionnaire was distributed to 28 highly-experienced interventional cardiologists ('Authors') from 13 Asia-Pacific countries. The results were discussed at a meeting on patient selection, technical consideration, deployment practices and patient management. Potential patient benefits of Absorb compared to metallic DES, the learning curve for patient selection and preparation, device deployment, and subsequent patient management approaches are presented.

CONCLUSIONS

Current practices are derived from guidelines optimized for European patients. Differences in approach exist in the Asia-Pacific context, including limited access to imaging and frequency of occurrence of complex lesions. Nevertheless, the use of the Absorb BVS ('Absorb') in certain Asia-Pacific countries has flourished and practices here are continuing to mature.

IVUS and OCT guided primary percutaneous coronary intervention for spontaneous coronary artery dissection with bioresorbable vascular scaffolds

Spontaneous coronary artery dissection (SCAD) is an uncommon but important cause of acute coronary syndrome. The diagnosis of SCAD by an angiogram alone can be challenging and the increasing use of intracoronary imaging has proven an invaluable diagnostic adjunct in this regard. The appropriate initial management of SCAD has been a matter of significant debate. Owing to frequent spontaneous healing of coronary dissection and a higher risk of complications with percutaneous coronary intervention (PCI) in the setting of SCAD, a default approach of mechanical revascularization is not recommended. However in the presence of vessel occlusion and on-going myocardial infarction PCI is mandated. Bioresorbable vascular scaffolds (BVS) offer potential advantages over the conventional stents in the setting of SCAD. We describe a state-of-the-art approach to the acute treatment of SCAD causing STEMI, utilizing intravascular ultrasound (IVUS), optical coherence tomography (OCT) and BVS and discuss management strategies for the modern era.

Prevalence of parameters of suboptimal scaffold deployment following angiographic guided bioresorbable vascular scaffold implantation in real world practice - an optical coherence tomography analysis

AIM

To assess the prevalence of suboptimal bioresorbable vascular scaffold (BVS, Abbott Vascular, Santa Clara, California) deployment in real world practice with intracoronary optical coherence tomography (OCT) imaging.

METHODS

Consecutive patients who underwent percutaneous coronary intervention using BVS and the final optimization assessed with OCT imaging in two tertiary care centers between December 2012 and February 2015 were evaluated for parameters of suboptimal scaffold deployment by OCT.

RESULTS

Overall, 36 scaffolds were implanted in 27 patients during this period. Mean age of the population was 54.7±8.2years and 19 (70.4%) were type B2/C lesions. The prevalence of parameters of suboptimal scaffold deployment were: underexpansion-22(61.1%), geographic miss-3(8.3%), tissue prolapse-7(25.9%), scaffold pattern irregularity-1(2.8%), longitudinal elongation-7(38.8%). Of the 7 overlaps imaged: excessive overlap was observed in 3 and scaffold gap in one. The median duration of follow up was 679days (range 193-963days). There were four events during this period. None were associated with suboptimal scaffold deployment.

CONCLUSION

OCT based parameters of suboptimal scaffold deployment are common in real world scenario and were not associated with adverse outcomes on long term follow up. These findings need to be confirmed in larger studies.

Use of 'Guideliner' catheter to overcome failure of delivery of Absorb™ Bioresorbable Vascular Scaffold in calcified tortuous coronary lesions: technical considerations in 'Real World Patients'

In our series of 177 real world patients (223 lesions) who underwent Absorb Bioresorbable Vascular Scaffold (BVS) implantation, 78 lesions were calcified and tortuous lesions. In four of these, despite adequate lesion bed preparation, appropriate guiding catheter support and use of buddy wires, the BVS failed to track through the proximal calcified and tortuous coronary anatomy (CTCA). "Guide Liner" catheter (GLC) had to be finally used to resuccessfully deliver and implant BVS to the lesion site. We report for the first time four cases of use of guideliner catheter to successfully overcome failed delivery of BVS to the lesion site through proximal CTCA, calcified and tortuous coronary artery (CTCA) lesions treated with Absorb™ BVS. Because the BVS is a large profile device, certain difficulties were encountered in delivering it through the GLC, which were finally overcome. We have therefore discussed the 'lessons and learnt' and "salient practice points" to enable successful delivery of BVS through the GLC.

Two-year Optical Coherence Tomography Findings after Balloon-Only Treatment of Bioresorbable Scaffold Restenosis in a Calcified Coronary Lesion: A Case Report

We report a case of a 65-year-old female patient treated with an everolimus-eluting bioresorbable scaffold (BRS) after rotational atherectomy of a severely calcified lesion of the left anterior descending coronary artery. The implanted BRS restenosed 10 months after implantation and was treated with a scoring balloon followed by drug-eluting balloons with good immediate and long-term results. To the best of our knowledge, this is the first report of a balloon-only treatment of a restenosis occurring more than 6 months after BRS implantation; angiographic and optical coherence tomography images after treatment and at two-year follow-up are presented.

Optical coherence tomography guidance for percutaneous coronary intervention with bioresorbable scaffolds

BACKGROUND

The effect of optical coherence tomography (OCT) guidance on the implantation strategy during all phases of percutaneous coronary intervention (PCI) with bioresorbable vascular scaffolds (BVSs) in a real-world scenario has been poorly investigated.

METHODS

Consecutive patients undergoing BVS implantation at our institution were included in this registry. Frequency-domain OCT pullbacks were performed at the operator's discretion during all phases of BVS implantation procedures to optimize preparation of lesions, confirm BVS size, and optimize expansion and apposition of scaffolds.

RESULTS

Between September 2012 and July 2015, 203 BVSs were implanted in 101 consecutive patients at our institution (2.01 BVSs/patient). In 66 patients, the procedure was performed under OCT guidance. In the OCT subgroup, 66 (77.6%) of the 85 treated lesions were complex (B2/C AHA/ACC type). Overall, 147 OCT pullbacks were performed and 72/147 (49.0%) pullbacks indicated the need for changing strategy. After angiography-only-guided optimisation of BVS in 27 (31.8%) lesions, an OCT examination prompted performance of a second post-expansion. This resulted in an increase in the minimal scaffold area (5.5 to 6.3mm(2), p=0.004) and a decrease in the incomplete scaffold apposition area (1.1 to 0.6mm(2), p=0.082), with no new stent fractures. When the population was divided according to the time of BVS implantation, an initial learning adaptation became evident, with the number of OCT-guided changes in strategy significantly decreasing between the initial and final time periods (p=0.017).

CONCLUSIONS

OCT guidance for BVS implantation significantly affects the procedural strategy, with favourable effects on acute results and the learning curve.