Impact of PSP Technique on Clinical Outcomes Following Bioresorbable Scaffolds Implantation

Two-Year Outcomes for Patients with Non-ST-Elevation Acute Coronary Syndrome Treated with Magmaris and Absorb Bioresorbable Scaffolds in Large-Vessel Lesions

BACKGROUND

The acute coronary syndrome (ACS) continues to be a fundamental indication for revascularization by percutaneous coronary intervention (PCI). Drug-eluting stent (DES) implantation remains a part of contemporary practice but permanent caging of the vascular structure with the metallic stent structure may increase the rate of device-related adverse clinical events. As an alternative to classic metallic DESs, the bioresorbable scaffolds (BRSs) have emerged as a temporary vascular support technology. We evaluated the mid-term outcomes of two generations of bioresorbable scaffolds-Absorb (Abbott-Vascular, Chicago, IL, USA) and Magmaris (Biotronik, Germany)-in patients with non-ST-elevation ACS.

METHODS

The study cohort consisted of 193 subjects after Magmaris implantation and 160 patients following Absorb implantation in large-vessel lesions.

RESULTS

At 2 years, a significantly lower rate of a primary outcome (cardiac death, myocardial infarction, stent thrombosis) was observed with Magmaris (5.2% vs. 15%; p = 0.002). In addition, we observed a significantly lower rate of MI in the target vessel (2.6% vs. 9.4%; p = 0.009) and a lower rate of scaffold thrombosis (0% vs. 3.7%; p = 0.008). The TLF rate between the two groups was not significantly different.

CONCLUSION

Magmaris demonstrated a good safety profile and more favorable clinical outcomes when compared to Absorb in patients with non-ST-elevation ACS.

Magnesium bioresorbable scaffold (Magmaris) versus polymer biodegradable ultrathin drug-eluting stent (Ultimaster) in acute coronary syndrome. Mid-term outcomes (2 years)

Introduction

Acute coronary syndrome (ACS) is a well-known risk factor for adverse clinical outcomes in percutaneous coronary intervention (PCI). Therefore, evaluation of coronary stents in this challenging clinical scenario can provide unique information on device safety and efficacy. Bioresorbable scaffolds (BRS) were designed to overcome long-term complications related to permanent vessel caging with a permanent metallic drug-eluting stent (DES).

Aim

We designed this study to evaluate the mid-term safety and efficiency of the Magmaris BRS in comparison to the leading new-generation ultrathin DES Ultimaster in the ACS population.

Material and methods

We present a retrospective analysis of 2-year follow-up data. The primary outcomes consisted of death from cardiac causes, myocardial infarction, and in-stent thrombosis. The second main study endpoint was defined as target-lesion failure (TLF).

Results

The study population consisted of two cohorts, the first of 193 patients treated with Magmaris implantation and the second of 169 patients treated with Ultimaster implantation. At the 2-year follow-up, there were no significant differences in both study cohorts in terms of primary outcome (5.1% vs. 11%; p = 0.051), and TLF (5.6% vs. 8%, p = 0.41).

Conclusions

Treatment with a second-generation BRS (Magmaris) versus a novel second-generation DES (Ultimaster) in non-ST-elevation acute coronary syndrome (NSTE-ACS) was associated with similar rates of target lesion failure at 2-year follow-up.

Four-year outcomes of a single-center experience with coronary everolimus-eluting bioresorbable scaffolds

BACKGROUND

Bioresorbable scaffolds (BRS) have been introduced to overcome the limitations of drug-eluting stents and the ABSORB (Everolimus-Eluting BRS, Abbott Vascular, Santa Clara, CA, USA) was the most extensively tested. Nevertheless, major RCTs reported higher rates of target lesion failures and BRS thrombosis at 3 years follow-up, bringing to the withdrawing of the device from the market. It has been suggested that a better lesions selection and an optimized implantation technique could mitigate the displayed adverse results.

METHODS

Consecutive patients undergoing BRS implantation were included in this observational, single center study. Clinical follow-up was conducted up to 4 years. Endpoint of interest was the target lesion failure (TLF), a composite outcome including cardiac death, target vessel myocardial infarction and target lesion revascularization.

RESULTS

A total of 62 patients with a mean age of 55±8.5 years were analyzed of which 70.9% presented with an acute coronary syndrome and 59.6% with myocardial infarction. A total of 100 lesions were treated and 51.6% were complex (B2/C). Predilatation was performed in all the case, post-dilatation in 74.1%. All the target vessel reference diameter (RVD) were >2.5 mm (average RVD 3.2±0.24 mm). At 4 years, the rate for TLF was 6.9%. Subgroup's analysis did not show significative differences among groups although consistently higher event rates were found for RVD <2.5 mm (12.6% vs. 6.4%, P=0.5), BRS overlapping (11.8% vs. 5%, P=0.2) and ticagrelor instead of clopidogrel on top of cardioaspirin (9.1% vs. 3%, P=0.2).

CONCLUSIONS

This small-sized real-world registry displays lower rates of clinical events during long-term follow-up in respect to previous studies. The avoidance of implantation in small vessels, inclusion of acute myocardial infarction and extensive performance of BRS post-dilatation could explain the observed better results. Long-term outcomes of the ongoing ABSORB IV Trial are needed to confirm this data.

Magnesium-based resorbable scaffold vs permanent metallic sirolimus-eluting stent in patients with ST-segment elevation myocardial infarction: 3-year results of the MAGSTEMI randomised controlled trial

BACKGROUND

The long-term safety and performance of magnesium-based bioresorbable scaffolds (MgBRS) in ST-segment-elevation myocardial infarction (STEMI) patients are uncertain.

AIMS

The aim of this study was to report the 3-year clinical outcomes of the MAGSTEMI trial.

METHODS

This investigator-driven, multicentre, randomised, single-blind, controlled trial randomised STEMI patients 1:1 to MgBRS or to permanent metallic sirolimus-eluting stents (SES) at 11 academic centres. The main secondary endpoints included device-oriented composite endpoints (DoCE) and patient-oriented composite endpoints (PoCE), their individual components, any bleeding, and device thrombosis rate. All endpoints were defined according to the Academic Research Consortium. Events were adjudicated by an independent committee.

RESULTS

Three-year clinical follow-up was obtained in 142 (90.0%) patients. At 3-year follow-up, MgBRS were associated with a higher rate of DoCE than SES (13 [17.6%] vs 5 [6.6%], diff -11.0 [95% CI: -21.3 to -0.7]; p=0.038). This difference was driven by an increased incidence of DoCE within the first year of follow-up. In the landmark analysis, there was no difference between 1 and 3 years (0 [0.0%] vs 1 [1.4%]; p=1.000). The difference in the rate of DoCE was driven by a higher incidence of target lesion revascularisation (TLR) in the MgBRS group compared to SES (12 [16.2%] vs 4 [5.3%]; diff -10.9% [95% CI: -20.7 to -1.2]; p=0.030). The difference in TLR was observed during the first year, with no further differences observed between 1 and 3 years (0 [0.0%] vs 1 [1.4%]; p=1.000).

CONCLUSIONS

At 3-year follow-up, MgBRS were associated with a higher rate of TLR, which was clustered within the first year, compared to SES.

Long-Term Outcomes After Implantation of Magnesium-Based Bioresorbable Scaffolds—Insights From an All-Comer Registry

Background

The magnesium-based sirolimus-eluting bioresorbable scaffold (Mg-BRS) Magmaris™ showed promising clinical outcomes, including low rates of both the target lesion failure (TLF) and scaffold thrombosis (ScT), in selected study patients. However, insights regarding long-term outcomes (&gt;2 years) in all-comer populations remain scarce.

Methods

We analyzed data from a single-center registry, including patients with acute coronary syndrome (ACS) and chronic coronary syndrome (CCS), who had undergone percutaneous coronary intervention (PCI) using the Mg-BRS. The primary outcome comprised the device-oriented composite endpoint (DoCE) representing a hierarchical composite of cardiac death, ScT, target vessel myocardial infarction (TV-MI), and clinically driven target lesion revascularization (TLR) up to 5 years.

Results

In total, 84 patients [mean age 62 ± 11 years and 63 (75%) men] were treated with the Mg-BRS devices between June 2016 and March 2017. Overall, 101 lesions had successfully been treated with the Mg-BRS devices using 1.2 ± 0.4 devices per lesion. Pre- and postdilatation using dedicated devices had been performed in 101 (100%) and 98 (97%) of all the cases, respectively. After a median follow-up time of 62 (61–64) months, 14 (18%) patients had experienced DoCEs, whereas ScT was encountered in 4 (4.9%) patients [early ScTs (&lt;30 days) in three cases and two fatal cases]. In 4 (29%) of DoCE cases, optical coherence tomography confirmed the Mg-BRS collapse and uncontrolled dismantling.

Conclusion

In contradiction to earlier studies, we encountered a relatively high rate of DoCEs in an all-comer cohort treated with the Mg-BRS. We even observed scaffold collapse and uncontrolled dismantling. This implicates that this metal-based BRS requires further investigation and may only be used in highly selected cases.

Five-year angiographic, OCT and clinical outcomes of a randomized comparison of everolimus and biolimus-eluting coronary stents with everolimus-eluting bioresorbable vascular scaffolds

Aims

To compare 5‐year angiographic, optical coherence tomography (OCT), and clinical outcomes between patients treated with bioresorbable vascular scaffolds (BVS) and drug‐eluting stents (DES).

Methods

The EverBio‐2 trial (Comparison of Everolimus‐ and Biolimus‐Eluting Coronary Stents with Everolimus‐Eluting Bioresorbable Vascular Scaffold) was a single‐center, assessor‐blinded, randomized controlled trial in which 240 patients were randomly allocated (1:1:1) to BVS, everolimus‐eluting (EES) or biolimus‐eluting (BES) DES. Clinical follow‐up was scheduled up to 5 years. All patients, alive and who did not have repeat revascularization of the target lesion during follow‐up were asked to return for angiographic follow‐up at 5 years.

Results

Five‐year angiographic follow‐up was completed in 122 patients (51%) and OCT analysis was performed in 86 (36%) patients. In‐stent late lumen loss was similar in both groups with 0.50 ± 0.38 mm in BVS versus 0.58 ± 0.36 mm in EES/BES, p = 0.20. Clinical follow‐up was complete in 232 patients (97%) at 5 years. The rate of the device‐oriented endpoint was 22% in the BVS and 18% in the EES/BES group (p = 0.49). The patient‐oriented composite endpoint occurred in 40% of BVS‐ and 43% of EES/BES‐treated patients (p = 0.72) at 5 years. No acute coronary syndrome due to stent thrombosis was detected after 2 years. Complete BVS strut resorption was observed at 5 years in the OCT subgroup.

Conclusion

Five‐year clinical outcomes were similar between BVS and DES patients as well as angiographic outcomes in a selected subgroup. However, a definitive conclusion cannot be drawn because the EverBio‐2 trial was not powered for clinical and angiographic endpoints at 5 years of follow‐up.

Bioresorbable Vascular Scaffolds-Dead End or Still a Rough Diamond?

Percutaneous coronary interventions with stent-based restorations of vessel patency have become the gold standard in the treatment of acute coronary states. Bioresorbable vascular scaffolds (BVS) have been designed to combine the efficiency of drug-eluting stents (DES) at the time of implantation and the advantages of a lack of foreign body afterwards. Complete resolution of the scaffold was intended to enable the restoration of vasomotor function and reduce the risk of device thrombosis. While early reports demonstrated superiority of BVS over DES, larger-scale application and longer observation exposed major concerns about their use, including lower radial strength and higher risk of thrombosis resulting in higher rate of major adverse cardiac events. Further focus on procedural details and research on the second generation of BVS with novel properties did not allow to unequivocally challenge position of DES. Nevertheless, BVS still have a chance to present superiority in distinctive indications. This review presents an outlook on the available first and second generation BVS and a summary of results of clinical trials on their use. It discusses explanations for unfavorable outcomes, proposed enhancement techniques and a potential niche for the use of BVS.

Incidental Finding of Strut Malapposition Is a Predictor of Late and Very Late Thrombosis in Coronary Bioresorbable Scaffolds

Malapposition is a common finding in stent and scaffold thrombosis (ScT). Evidence from studies with prospective follow-up, however, is scarce. We hypothesized that incidental observations of strut malapposition might be predictive of late ScT during subsequent follow-up. One hundred ninety-seven patients were enrolled in a multicentre registry with prospective follow-up. Optical coherence tomography (OCT), performed in an elective setting, was available in all at 353 (0–376) days after bioresorbable scaffold (BRS) implantation. Forty-four patients showed evidence of malapposition that was deemed not worthy of intervention. Malapposition was not associated with any clinical or procedural parameter except for a higher implantation pressure (p = 0.0008). OCT revealed that malapposition was associated with larger vessel size, less eccentricity (all p < 0.01), and a tendency for more uncovered struts (p = 0.06). Late or very late ScT was recorded in seven of these patients 293 (38–579) days after OCT. OCT-diagnosed malapposition was a predictor of late and very late scaffold thrombosis (p < 0.001) that was independent of the timing of diagnosis. We provide evidence that an incidental finding of malapposition—regardless of the timing of diagnosis of the malapposition—during an elective exam is a predictor of late and very late ScT. Our data provide a rationale to consider prolonged dual antiplatelet therapy if strut malapposition is observed.

Long-term clinical results of biodegradable vascular scaffold ABSORB BVS™ using the PSP-technique in patients with acute coronary syndrome

BACKGROUND

The PSP (predilatation, sizing, post-dilatation)-technique was developed to improve the prognosis of patients after bioresorbable vascular scaffold (BVS) implantation. In acute coronary syndrome (ACS) the use of BVS is particularly demanding and carries some potential risk regarding aggressive lesion preparation, proper vessel sizing due to spasm and thrombus inside the artery. The aim herein, was to determine the long-term results of BVS stenting in ACS patients depending on the scaffold implantation technique.

METHODS

The present study is a prospective, two-center study, which consisted of 182 patients who underwent percutaneous coronary intervention (PCI) with BVS (Absorb, Abbott Vascular, Santa Clara, California, USA) implantation for the ACS. All patients were divided into two groups. The first consisted of 52 patients treated with the PSP-technique (PSP group). The second group enrolled 130 patients treated with a non-PSP procedure (non-PSP group).

RESULTS

The procedure was successful in all patients. The mean observation time was 28.8 ± 16.5 months (median 28.3 months, interquartile range 24.0 [17.0-41.0] months). It was found that target vessel failure (TVF) was consistently reduced in patients using the PSP-technique as compared with the non-PSP group (5.8% vs. 17.7%, p = 0.03). Moreover, PSP-technique was superior to non-PSP-technique concerning major adverse cardiac events (MACE) (3.7% vs. 22.3%, p = 0.02). Logistic regression analysis revealed that the use of PSP technique significantly decreased the risk of target vessel revascularization (odds ratio [OR] 0.11, p = 0.01), TVF (OR 0.28, p = 0.03) and MACE (OR 0.29, p = 0.02).

CONCLUSIONS

The PSP-technique for BVS implantation improves long-term results and should also be recommended for newer generations of the bioresorbable scaffold.