Predictors of scaffold failure and impact of optimized scaffold implantation technique on outcome: Results from the German-Austrian ABSORB RegIstRy

AIMS

We aimed to investigate predictors of scaffold failure and the potential impact of an optimized scaffold implantation technique by means of a learning curve on long-term clinical outcome after bioresorbable scaffold (BRS) implantation and to evaluate predictors of scaffold failure.

METHODS AND RESULTS

A total of 3326 patients were included in this prospective, observational, multi-center study (ClinicalTrials.gov NCT02066623) of consecutive patients undergoing BRS implantation between November 2013 and January 2016. The 3144 patients completed follow-up after 24 months, 3265 patients were eligible for time-to-event-analysis. Clinical endpoints were major adverse cardiac events-a composite endpoint of death, target vessel revascularization and myocardial infarction, and scaffold thrombosis (ScT). Patients were grouped according to treatment before or since 2015. During follow-up MACE rate improved from 2.52% after 30 days, 5.45% after 6 months and 12.67% after 24 months to 1.52%, 3.44%, and 10.52%, respectively. A total of 75 ScT occurred. In multiple regression analysis, treatment of bifurcations, long lesions, and procedures performed earlier than 2014 were identified as predictors for the occurrence of ScT.

CONCLUSION

Treatment of bifurcation lesions is the strongest predictor of ScT following BRS implantation. A significantly lower incidence of ScT and 24-month target lesion revascularization in patients recruited after 2014 into our observational registry suggests the influence of a learning curve.

Comparison of the everolimus-eluting bioresorbable vascular scaffold versus the everolimus-eluting metallic stent in real-world patients with ST-segment elevation myocardial infarction

INTRODUCTION

Despite the withdrawal of the ABSORB bioresorbable vascular scaffold (BVS) from clinical use, continuous observation of BVS-treated patients is necessary. In the vast majority of clinical trials, patients with ST-segment elevation myocardial infarction (STEMI) were excluded from the analysis.

AIM

To compare the early and long-term outcomes of the BVS with the everolimus-eluting metallic stent (EES) in patients with STEMI.

MATERIAL AND METHODS

Consecutive patients treated with BVS or EES in our center were screened. For analysis, only patients with STEMI were enrolled. The primary endpoint was a comparison of the target lesion failure at 12 and 24 months. The secondary endpoints encompass occurrence of the patient-oriented cardiovascular endpoint (PoCE), stent thrombosis (ST), device, and procedural success.

RESULTS

Between 2012 and 2016, 2,137 patients were hospitalized for STEMI. Of these, 123 patients received the BVS (163 scaffolds; 151 lesions), whereas in 141 patients the EES (203 stents; 176 lesions) was implanted. The median follow-up was 931 ±514 days. The primary endpoint at 12 months occurred in 9.7% in the BVS group and in 8.5% in the EES group (hazard ratio (HR) = 2.61; 95% confidence interval (CI): 0.90-7.56; p = 0.076). At 24 months the incidence of the primary endpoint was 15.2% in the BVS group and 14.9% in the EES group (HR = 2.46; 95% CI: 0.85-7.07; p = 0.095). The rates of PoCE, ST, device, and procedural success were also comparable in both groups.

CONCLUSIONS

STEMI patients treated with the BVS showed statistically similar rates of primary and secondary endpoints compared with the EES.

Weighing the potential late benefits versus early hazard associated with bioresorbable vascular scaffolds in percutaneous coronary interventions: a Markov decision analytic model

OBJECTIVE

Use of poly-L-lactic acid-based bioresorbable scaffolds (BRS) has been associated with increased risk of device thrombosis during the first 3 years after implantation as compared to metallic everolimus-eluting stents (EES). The long-term performance of BRS relative to EES remains unknown.

METHODS

We used a Markov decision analysis model to evaluate the effectiveness of BRS vs. EES over a lifetime horizon. In addition to one-way sensitivity analyses of key variables, we evaluated the impact of optimal implantation technique and limiting procedures to larger vessels (>2.6 mm in diameter) on model results.

RESULTS

Assuming no risk of target lesion revascularization for BRS after 3 years, we found a small increment in quality-adjusted life expectancy (QALE) of 0.02 with the use of BRS relative to EES, with benefit being observed after 21.8 years. Optimal implantation technique and limiting to larger vessels resulted in larger gains in QALE (0.08 and 0.06, respectively) with BRS and shorter times to equipoise (6.7 and 8.3 years, respectively). Model results were highly sensitive to variations in the relative risk of stent thrombosis (BRS vs. EES).

CONCLUSIONS

Based on currently available data, it would take approximately 21.8 years for the presumed late benefits of current BRS relative to EES to overcome the early hazard associated with their use under favorable assumptions. Optimal implantation technique and limiting procedures to larger vessels improved BRS performance and reduced time to equipoise. Eliminating the higher BRS thrombosis risk is necessary in developing future generations of BRS as an acceptable alternative to EES.

Twelve-month outcomes after bioresorbable vascular scaffold implantation in patients with acute coronary syndromes. Data from the European Multicenter GHOST-EU Extended Registry

AIMS

The aim of this study was to report on the midterm outcomes of patients undergoing percutaneous coronary intervention with bioresorbable vascular scaffolds (BVS) for the treatment of acute coronary syndromes (ACS) and compare with those of patients with stable coronary artery disease (sCAD).

METHODS AND RESULTS

One thousand four hundred and seventy-seven (1,477) patients underwent implantation of one or more BVS (Absorb BVS; Abbott Vascular, Santa Clara, CA, USA) at 11 European centres and were included in the GHOST-EU registry. Admissions comprised 47.1% of the patients (951 BVS) with ACS, and 52.8% (1,274 BVS) with sCAD. During a median follow-up of 384 (359-460) days, patient-oriented endpoints (PoCE), including all-cause death, any infarction, any revascularisation, were recorded in 271 patients (12-month incidence in ACS patients: 18.5% vs. 11.6% in the sCAD group, p<0.001). Device-oriented composite endpoints (DoCE), cardiac death, target vessel infarction and target lesion revascularisation, were observed in 98 patients (12-month incidence of 4.2% in the sCAD group, 6.4% in the ACS group; p=0.052). The 12-month incidence of definite scaffold thrombosis was 2.6% in ACS patients and 0.8% in XIENCE patients (p=0.006). In multivariate analysis, ACS was a predictor of DoCE (HR: 2.26 [1.34-3.81], p=0.002), PoCE (HR: 1.71 [1.13-2.58], p=0.011), and stent thrombosis (HR: 2.51 [1.13-5.60], p=0.025). In contrast, the incidence of target lesion revascularisation was not different between groups. There was no difference in the incidence of any of these endpoints among the different clinical presentations (unstable angina, non-ST-elevation infarction and ST-elevation infarction).

CONCLUSIONS

PoCE, DoCE and scaffold thromboses were more frequent in ACS patients, without any difference among different forms of ACS.

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).

Possible mechanical causes of scaffold thrombosis: insights from case reports with intracoronary imaging

The advent of intracoronary stents has greatly increased the safety and applicability of percutaneous coronary interventions. One of the drawbacks of drug-eluting stents (DES) is the increased risk of late and very late stent thrombosis (ST). It was anticipated that the risks of ST after DES implantation would be solved with the advent of fully biodegradable scaffolds, which offer the possibility of transient scaffolding of the vessel to prevent acute vessel closure and recoil while also transiently eluting an antiproliferative drug to counteract constrictive remodelling and excessive neointimal hyperplasia. In spite of the enthusiasm for the concept of bioresorbable scaffolds, current clinical data on the Absorb bioresorbable vascular scaffold (BVS) have generated concerns about scaffold thrombosis (ScT) in both the early and late phases. However, the causes of ScT in both the early and late phases have yet to be fully elucidated. This article seeks to provide insights into the possible mechanical causes of ScT in the early and late phases with data stemming from intracoronary imaging (intravascular ultrasound and optical coherence tomography) of the currently published ScT cases following the implantation of BVS and reviews the practical recommendations for implantation of the BVS made by a group of experts.

Clinical and angiographic outcome of a single center, real world population treated with a dedicated technique of implantation for bioresorbable vascular scaffolds. The FAtebenefratelli Bioresorbable Vascular Scaffold (FABS) registry

OBJECTIVES

With this prospective study we aim at investigating the long-term outcome of a consecutive cohort of patients successfully treated with bioresorbable scaffold (BVS) implantation.

BACKGROUND

It is not clearly understood if there is a relation between the technique of BVS implantation and the outcome.

METHODS

Between December 2012 and December 2014, all consecutive patients treated with BVS were included in this registry and received an angiographic follow-up. After a run-in phase, all BVS were implanted using a specific technique consisting of aggressive predilation, correct scaffold sizing, visually determined, and high-pressure post-dilation with a noncompliance balloon. Primary endpoint was late lumen loss (LLL) at 1-year angiographic follow-up and ischemia-driven target-lesion revascularization (ID-TLR) at 2-year clinical follow-up. Secondary endpoints were the occurrence of binary restenosis, major adverse cardiac events (MACE), and every single component of MACE (cardiac death, myocardial infarction, TLR) at 2 years.

RESULTS

A total of 144 lesions in 122 patients treated consecutively with BVS, were enrolled. Diabetics were 29.5% and acute coronary syndrome at presentation occurred in 29.5% of patients. At the angiographic follow-up LLL was 0.38 ± 0.9. At 2-year clinical follow-up, ID-TLR occurred in eight patients (5.6%). We observed two cases of scaffold thrombosis (1.38%, one early and one very late). At multivariate statistical analysis, STEMI presentation remained a significant predictor for TLR.

CONCLUSIONS

In a complex, all-comers real world population, BVS implantation with a specific, and standardized technique showed to be feasible, with acceptable mid-term angiographic and long-term clinical outcome.

Patient profile and periprocedural outcomes of bioresorbable vascular scaffold implantation in comparison with drug-eluting and bare-metal stent implantation. Experience from ORPKI Polish National Registry 2014-2015

INTRODUCTION

There are limited data on the comparison of bioresorbable vascular scaffold (BVS) and drug-eluting stent (DES)/bare-metal stent (BMS) implantation in an unselected population of patients with coronary artery disease.

AIM

To compare the periprocedural outcomes and patient profile of BVS and DES/BMS implantation in an all-comer population from the ORPKI Polish National Registry.

MATERIAL AND METHODS

A total of 141,324 consecutive patients from 151 invasive cardiology centers in Poland were included in this prospective registry between January 2014 and June 2015. Periprocedural data on patients with at least one BVS (Absorb, Abbott Vascular, Santa Clara, CA, USA), DES or BMS (all available types) implantation in de novo lesions during index percutaneous coronary intervention for stable angina (SA) or acute coronary syndrome were collected.

RESULTS

Bioresorbable vascular scaffold was the most often used in patients with SA, in single-vessel disease and in younger male patients. Bioresorbable vascular scaffold implantation was significantly more often associated with periprocedural administration of ticagrelor/prasugrel (6.8% vs. 3.6%; p = 0.001) and use of intravascular ultrasound and optical coherence tomography in comparison with the DES/BMS group (2.8% vs. 0.6% and 1.8% vs. 0.1%, respectively; p = 0.001 for both). The incidence of periprocedural death was significantly lower in the BVS group than the DES/BMS group (0.04% vs. 0.32%; p = 0.02), but this difference was no longer significant after adjustment for covariates. On the other hand, coronary artery perforation occurred significantly more often during BVS delivery (0.31% vs. 0.12%; p = 0.01), and BVS implantation was identified as an independent predictor of coronary artery perforation in multivariate logistic regression analysis (OR = 6.728, 95% CI: 2.394-18.906; p = 0.001).

CONCLUSIONS

Patients treated with BVS implantation presented an acceptable safety and efficacy profile in comparison with the DES/BMS group. However, lower risk patients were the most frequent candidates for BVS implantation.

A prospective evaluation of a standardized strategy for the use of a polymeric everolimus-eluting bioresorbable scaffold in ST-segment elevation myocardial infarction: Rationale and design of the BVS STEMI STRATEGY-IT study

OBJECTIVES

To assess the feasibility and the clinical results following a prespecified bioresorbable vascular scaffold (Absorb BVS) implantation strategy in ST-elevation myocardial infarction (STEMI) patients.

BACKGROUNDS

Concerns raised about the BVS safety in STEMI setting because a not negligible thrombosis rate was reported within 30 days and 12 months after implantation. Technical procedural issues related to the structural BVS features were advocated as probable causes for the thrombotic events.

METHODS

This is an investigators-owned and -directed, prospective, nonrandomized, single-arm multicenter registry intended to obtain data from 500 consecutive STEMI patients undergoing primary PCI with BVS (1.1 or GT1) following a prespecified implantation protocol. The study is recorded in ClinicalTrials.gov with the identifier: NCT02601781.

RESULTS

The primary endpoint is a device-oriented composite end-point (DOCE) of cardiac death, any myocardial infarction clearly attributable to the intervention culprit vessel and ischemic-driven target lesion revascularization within 30 days after the index procedure. The DOCE will be assessed even at 6-month, 1-, 3-, and 5-year follow-up.

CONCLUSIONS

This will be the first study investigating the feasibility and the early- and long-term clinical impact of a prespecified BVS implantation protocol in thrombotic lesions causing STEMI. Here, we describe the rationale and the design of the study. © 2016 Wiley Periodicals, Inc.

Scaffold Thrombosis After Percutaneous Coronary Intervention With ABSORB Bioresorbable Vascular Scaffold: A Systematic Review and Meta-Analysis

OBJECTIVES

The aim of this study was to determine the risk of scaffold thrombosis (ST) after percutaneous coronary intervention (PCI) with placement of an ABSORB bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, California) by conducting a systematic review and meta-analysis.

BACKGROUND

PCI with BVS placement holds great potential, but concern has recently been raised regarding the risk of ST.

METHODS

MEDLINE/PubMed, Cochrane CENTRAL, and meeting abstracts were searched for all studies that included outcomes data for patients after PCI with BVS placement. For studies comparing BVSs with drug-eluting stents (DES), pooled estimates of outcomes, presented as odds ratios (ORs) with 95% confidence intervals (CIs), were generated with random-effects models.

RESULTS

Our analysis included 10,510 patients (8,351 with a BVS and 2,159 with DES) with a follow-up of 6.4 ± 5.1 months and 60 ± 11 years of age; 78% were male, 36% had stable angina, and 59% had acute coronary syndrome (ACS). Among patients with a BVS, cardiovascular death occurred in 0.6%, myocardial infarction (MI) in 2.1%, target lesion revascularization in 2.0%, and definite/probable ST in 1.2% of patients. Of BVS patients, 0.27% had acute ST and 0.57% had subacute ST. Meta-analysis demonstrated that patients who received a BVS were at a higher risk of MI (OR: 2.06, 95% CI: 1.31 to 3.22, p = 0.002) and definite/probable ST (OR: 2.06, 95% CI: 1.07 to 3.98, p = 0.03) compared with patients who received DES, whereas there was a trend toward decreased all-cause mortality with a BVS (OR: 0.40, 95% CI: 0.15 to 1.06, p = 0.06).

CONCLUSIONS

Patients undergoing PCI with a BVS had increased definite/probable ST and MI during follow-up compared with DES. Further studies with long-term follow-up are needed to assess the risk of ST with a BVS.

Two-year clinical outcomes of Absorb bioresorbable vascular scaffold implantation in complex coronary artery disease patients stratified by SYNTAX score and ABSORB II study enrolment criteria

AIMS

This study presents the two-year clinical outcomes of the Amsterdam ABSORB registry stratified by lesion and patient characteristics complexity (SYNTAX score and ABSORB II study enrolment criteria).

METHODS AND RESULTS

Patients treated with BVS were included in this prospective registry and stratified according to the ABSORB II trial inclusion and exclusion criteria and the SYNTAX score. The registry comprises 135 patients (59±11 years, 73% male, 18% diabetic) with 159 lesions. Median follow-up duration was 774 days (742-829). Median SYNTAX score was 11.5 (Q1-Q3: 6-17.5). Two-year event rates were cardiac death 0.7%, MI 5.3%, TVR 13.6%, TLR 11.4%, definite ST 3.0% and TVF 14.4%, respectively. Stratified analyses showed a significantly higher revascularisation rate in patients not meeting ABSORB II criteria (TVR: 2.3% vs. 19.2%, p=0.010, and TLR: 2.3% vs. 15.8%, p=0.025) and patients with SYNTAX score ≥11.5 (TVR: 4.8% vs. 21.8%, p=0.006, and TLR: 3.2% vs. 17.4%, p=0.007).

CONCLUSIONS

The use of Absorb BVS in patients meeting the ABSORB II trial inclusion criteria or those with low SYNTAX scores is associated with acceptable clinical outcomes at two-year follow-up. Patients with more complex characteristics have significantly higher revascularisation rates.

Bioresorbable Coronary Scaffold Thrombosis: Multicenter Comprehensive Analysis of Clinical Presentation, Mechanisms, and Predictors

BACKGROUND

Recent reports suggest an elevated incidence of bioresorbable vascular scaffold (BVS) thrombosis (scaffold thrombosis [ScT]).

OBJECTIVES

This study investigated occurrence rates, clinical and angiographic characteristics, and possible mechanisms of ScT in all-comer patients undergoing BVS implantation at 2 German and 2 Swiss hospitals.

METHODS

A total of 1,305 consecutive patients (mean age 64 years, 78% male) who received 1,870 BVS (mean 1.4 ± 0.8 BVS/patient) were enrolled. Clinical/procedural characteristics, mortality, and ScT data at 485 days (range 312 to 652 days) were examined.

RESULTS

ScT occurred in 42 patients. The incidence of probable and definite ScT was 1.8% at 30 days and 3.0% at 12 months, without differences among centers (p = 0.60). A total of 22 (52%) ScTs presented as ST-segment elevation myocardial infarction and 6 (17%) as sudden cardiac death. In multivariable analysis, ostial lesions (p = 0.049) and impaired left ventricular ejection fraction (p = 0.019) were independently associated with ScT. Nine (21%) of the ScTs occurred in patients who had suspended dual antiplatelet therapy, in 6 cases prematurely. Lower post-procedural minimum lumen and reference vessel diameters were hallmarks of ScT (all p < 0.0001). The risk of ScT appeared to rapidly increase for post-procedural minimum lumen diameters below 2.4 mm (for the 2.5- to 3.0-mm BVS) and 2.8 mm (for the 3.5-mm BVS). When a BVS-specific implantation strategy was implemented, 12-month ScT rates fell from 3.3% to 1.0%, an effect that remained significant when adjusted for multivariable propensity score (p = 0.012; hazard ratio: 0.19; 95% confidence interval: 0.05 to 0.70).

CONCLUSIONS

The 12-month incidence of ScT reached 3% and could be significantly reduced when an optimized implantation strategy was employed. (retrospective multicentric registry and Mainz Intracoronary Database. The Coronary Slow-flow and Microvascular Diseases Registry [MICAT]; NCT02180178).

The ABSORB bioresorbable vascular scaffold: A novel, fully resorbable drug-eluting stent: Current concepts and overview of clinical evidence

The advent of fully bioresorbable stent technology and specifically the ABSORB™, a bioresorbable vascular scaffold (BVS) stent, is heralded as breakthrough technology in the current era of percutaneous coronary interventions. This article reviews the current understanding of this technology along with the clinical evidence from trials and registries of ABSORB BVS that included patients with both simple as well as more complex "real-world" coronary lesions. In addition, considering the current limitations of this device-mostly associated with the mechanical properties of the polymeric scaffold structure-a review of guidelines on successful implantation of the ABSORB BVS is presented. Although expert feedback suggests extensive use of this device in routine clinical practice outside the United States despite a paucity of data on long-term safety in this setting, attention to procedural details and implantation technique is obligatory to achieve optimal clinical outcomes.

Absorb bioresorbable stents for the treatment of coronary artery disease

Bioresorbable stents are considered to be the 'fourth revolution' in percutaneous coronary intervention. The first clinically available Absorb(®) bioresorbable device is made of poly-l-lactic acid polymer and elutes everolimus. The process of bioresorption is completed in 3 years. The introduction of this device into clinical practice went through several logical phases: first-in-man studies, randomized Absorb II study with moderately complex patients and lesions, registries of real life patient population and reports of challenging cases. The procedural results are excellent; many insights have been gained by intracoronary imaging. Intermediate-term outcomes are very encouraging both from imaging and from clinical perspectives. The issue of increased stent thrombosis rate was raised in one study, but other studies have been reassuring. Excellent lesion preparation, sizing and complete expansion of the Absorb device are crucial for optimal procedural and clinical results. Results of ongoing large randomized studies will determine the future role of this technology.

Bioresorbable scaffold - A magic bullet for the treatment of coronary artery disease?

Today, drug-eluting metal stents are considered the gold standard for interventional treatment of coronary artery disease. While providing inhibition of neointimal hyperplasia, drug-eluting metal stents have many limitations such as the risk of late and very late stent thrombosis, restriction of vascular vasomotion and chronic local inflammatory reaction due to permanent implantation of a 'metallic cage', recognized as a foreign body. Bioresorbable scaffold stents (BRS) are a new solution, which is trying to overcome the limitation of the 'metallic cage'. This structure provides short-term scaffolding of the vessel and then disappears, leaving nothing behind. The purpose of this review is to present the theoretical rationale for the use of BRS and to outline the clinical outcomes associated with their use in terms of data obtained from RCTs, clinical trials, registries and real life use. We have also tried to answer all questions on this intervention based on available data, with a focus on ABSORB BVS (Abbott Vascular, Santa Clara, USA). We consider that this new technology can be the "magic bullet" to treat coronary artery disease.

Clinical Outcomes of Bioresorbable Scaffold in Coronary Artery Disease: A Systematic Literature Review

OBJECTIVES

We aim to perform a systematic literature review on all studies reporting the clinical outcomes of the use of bioresorbable scaffolds (BRS) in different settings of coronary artery disease (CAD).

BACKGROUND

BRS are designed to provide early support of the vessel wall postangioplasty, deliver antiproliferative agents to prevent excessive hyperplastic healing responses and finally "disappear" when no longer required. Emerging data have provided evidence of their use in specific clinical scenarios.

METHODS

A comprehensive literature search was performed by 2 independent reviewers utilizing MEDLINE, EMBASE, and Cochrane Library databases. The only 2 CE marked BRS: everolimus-eluting Bioresorbable vascular scaffold ABSORB BVS and the myolimus-eluting DESolve Bioresorbable Coronary Scaffold (BCS) System were included.

RESULTS

The studies were categorized into: ST elevation myocardial infarction (STEMI), stable CAD, and "all-comers" group. Thirty-one studies were included; 8 in STEMI patients (all ABSORB), 15 in stable CAD patients. In the STEMI group (n = 606), acute procedural success ranged from 96% to 100%, cardiac mortality 0-9.1%, recurrent MI and stent thrombosis rates were 0-4.3%. In the stable CAD group, the 13 ABSORB studies (n = 3259) demonstrated cardiac mortality rate of 0-0.6%, recurrent MI rate 0-4.5%, and stent thrombosis rate 0-4.3%

CONCLUSIONS

Current clinical data suggest the BRS, especially the ABSORB BVS, may represent a reasonable alternative to DES in uncomplicated coronary anatomy.

Mid-term clinical outcomes of ABSORB bioresorbable vascular scaffold implantation in a real-world population: A single-center experience

BACKGROUND

Available data on the use of the ABSORB bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, CA) in real-world patients is limited. The aim of this study was to assess the mid-term clinical outcomes in a real-world population treated with ABSORB BVS.

METHODS AND MATERIALS

We retrospectively evaluated all patients treated with ABSORB at Papworth Hospital, Papworth Everard, UK between July 2012 and July 2014. A total of 108 patients (126 lesions) were identified. Clinical follow-up was performed on all subjects by clinic visit or telephone interview.

RESULTS

Most patients were male (91.7%) with a relative high incidence of previous myocardial infarction (MI) (40.7%). Clinical presentation was equally divided between stable angina and acute coronary syndrome (ACS) (51.8% vs. 48.2%, p=0.59). Of the ACS patients, 26.9% presented with ST-elevation myocardial MI. Intravascular imaging was used in all cases. Predilatation (92.9%) and postdilatation (82.5%) were frequently performed. Major adverse cardiac event (MACE) rates defined as the composite of all-cause death, follow-up MI and target vessel revascularization were 2.5% at 6-month and 4.5% at 1-year. The 1-year target lesion failure rate, defined as the composite of cardiac death, target-vessel MI and target lesion revascularization was 1.9%. There was 1 case of subacute stent thrombosis.

CONCLUSIONS

The use of ABSORB BVS in real-world patients appears to be associated with good mid-term clinical outcomes when guided by intravascular imaging. Larger studies are required to evaluate further the role of BVS in routine clinical practice and examine how this compares to metallic devices.

SUMMARY

Available data on the use of the ABSORB BVS in real-world patients is limited. We retrospectively evaluated all patients treated with ABSORB BVS between July 2012 and July 2014. A total of 108 patients (126 lesions) were identified. Clinical presentation was equally divided between stable angina and acute coronary syndrome (51.8% vs. 48.2%, p=0.59). Predilatation (92.9%) and postdilatation (82.5%) were frequently performed. Estimated MACE rates at 6-month and 1-year were 2.5% and 4.5% respectively, with a 1-year TLF rate of 1.9%. These results suggest that the use of ABSORB BVS use in the real-world is associated with good mid-term clinical outcomes when guided by intravascular imaging.

Bioresorbable vascular scaffold implantation in acute coronary syndromes: clinical evidence, tips and tricks

Percutaneous coronary intervention (PCI) with a drug-eluting stent (DES) is routine treatment for patients with acute coronary syndromes (ACS). However, permanent metallic caging of the vessel has several shortcomings, such as side branch jailing and impossibility of late lumen enlargement. Moreover, DES PCI is affected by vasomotion impairment. In ACS a high thrombus burden and vasospasm lead to a higher risk of acute and late acquired stent malapposition than in stable patients. This increases the risk of acute, late and very late stent thrombosis. In this challenging clinical setting, the implantation of bioresorbable vascular scaffolds (BVS) could represent an appealing therapeutic option. Temporary vessel scaffolding has proved to have several advantages over metallic stent delivery, such as framework reabsorption, late lumen enlargement, side branch patency, and recovery of physiological reactivity to vasoactive stimuli. In the thrombotic environment of ACS, BVS implantation has the benefit of capping the thrombus and the vulnerable plaque. Bioresorbable vascular scaffolds also seems to reduce the incidence of angina during follow-up. Acute coronary syndromes patients may therefore benefit more from temporary polymeric caging than from permanent stent platform implantation. The aim of this review is to update the available knowledge concerning the use of BVS in ACS patients, by analyzing the potential pitfalls in this challenging clinical setting and presenting tricks to overcome these limitations.

Clinical Comparison With Short-Term Follow-Up of Bioresorbable Vascular Scaffold Versus Everolimus-Eluting Stent in Primary Percutaneous Coronary Interventions

Objective of this study was to assess the clinical performance of bioresorbable vascular scaffold (BVS) compared to everolimus-eluting stent (EES) in subjects with ST-segment elevation myocardial infarction (STEMI). We included all consecutive patients with STEMI who underwent percutaneous coronary intervention (PCI) with BVS implantation in centers participating to the Italian ABSORB Prospective Registry (BVS-RAI) and PCI with EES in the same centers during the same period. The 2 groups were compared. The primary end point was patient-oriented composite end point (POCE) including cardiac death, myocardial infarction, and target lesion revascularization (TLR) at the longest available follow-up. BVS or EES thrombosis at follow-up was also evaluated. Of the 563 patients with STEMI included, 122 received BVS and 441 EES. Procedural success was obtained in 549 (97.5%) cases without significant differences between the 2 groups (BVS 99.3% vs EES 97.0%, p = 0.2). At a median of 220-day (interquartile range 178 to 369) follow-up, no significant differences were observed in terms of POCE (BVS 4.9% vs EES 7.0%, p = 0.4); death (BVS 0.8%, EES 2.0%, p = 0.4), MI (BVS 4.1%, EES 2.0%, p = 0.2), TLR (BVS 4.1%, EES 4.5%, p = 0.8), device thrombosis (BVS 2.5%, EES 1.4%, p = 0.4). All TLR cases were successfully managed with re-PCI in both groups. A propensity matching of the study populations showed no significant differences regarding POCE at the longest available follow-up (odds ratio 0.53, 0.1 to 4.3). In conclusion, in this direct prospective comparison, BVS was associated with similar clinical results compared to EES in the STEMI setting. Larger and adequately powered randomized trials are needed to fully assess the potential clinical benefit of BVS versus the current standard of care in patients with STEMI.

Absorb bioresorbable vascular scaffold: What have we learned after 5 years of clinical experience?

Bioresorbable scaffolds have the potential to introduce a paradigm shift in interventional cardiology, a true anatomical and functional "vascular restoration" instead of an artificial stiff tube encased by persistent metallic foreign body. Early clinical studies using the first commercially available drug-eluting bioresorbable vascular scaffold (BVS) reported very promising safety and efficacy outcomes, comparable to best-in-class second-generation drug-eluting metal stent. To date, more than 60,000 Absorb BVSs have been implanted with only the interim analysis of one randomized trial (ABSORB II RCT) available. Recent registries have challenged the initial claim that BVS is immune from Scaffold Thrombosis (ST). However, suboptimal device expansion and insufficient intracoronary imaging guidance can explain higher than expected ST, especially in complex lesions. The aim of this review article is to critically evaluate the results of the available Absorb BVS studies and discuss the lessons learned to optimize lesion selection and implantation technique of such devices.

ST-segment elevation myocardial infarction – ideal scenario for bioresorbable vascular scaffold implantation?

Bioresorbable vascular scaffolds (BVS) represent a breakthrough technology for percutaneous coronary intervention (PCI). In this context, because of the unique properties of bioresorbable devices, ST-segment elevation myocardial infarction (STEMI) may represent the ideal scenario for BVS implantation. Consistently, 57% of physicians declare they currently use BVS in this group of patients. However, continuous and growing evidence on the good performance of these devices has been actually shown only in small studies with short- and mid-term follow-up. For these reasons, we need data from sufficiently large observational studies, with long-term follow-up, to confirm that BVS can deliver the same results as 2nd-generation drug-eluting stents when using an appropriate implantation technique. In this review, we discuss the potential advantages of BVS implantation in STEMI patients, together with the most recent evidence from clinical studies, highlighting safety and procedural concerns.