Outcome of a polymer-free drug-coated coronary stent in bifurcation lesions-Pilot registry with serial OCT imaging

BACKGROUND

Polymer-free and carrier-free drug-coated stents (DCS) represent a novel therapeutic option for the treatment of coronary artery disease. The objective of this pilot registry is to evaluate the safety and efficacy of DCS implantation in bifurcation lesions.

METHODS

Overall, 23 consecutive patients with 24 lesions received a Biolimus A9-coated DCS for coronary bifurcation lesions. Patients were examined with quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 3-6 months of follow-up.

RESULTS

A total of 23 patients with 24 bifurcation lesions were included in this study. Nine (33.3%) lesions of eight patients revealed angiographical target lesion failure due to in-stent restenosis (ISR). In total, 19 patients with 20 bifurcation lesions were suitable for OCT analysis. A total of 2936 struts were analyzed and 14 struts (0.47%) were classified as malapposed. The mean luminal area (mm2) was not different in lesions with ISR vs. lesions with no ISR (5.07 ± 2.0 vs. 5.73 ± 1.34, p = 0.39) at follow-up. Lesions with ISR showed higher mean neointimal burden (27.11 ± 10.59 vs. 13.93 ± 9.16%, respectively; p = 0.009). All of the patients who presented with significant ISR required percutaneous re-intervention.

CONCLUSIONS

We observed a high rate of DCS ISR in bifurcation lesions, possibly related to increased inflammation and neoatherosclerosis. The small size of the study warrants careful interpretation of our results. Larger trials are necessary to expand knowledge of these findings.

Real-world reasons and outcomes for 1-month versus longer dual antiplatelet therapy strategies with a polymer-free BIOLIMUS A9-coated stent

BACKGROUND

A large trial established the favorable profile of a new polymer-free biolimus A9-eluting stent (PF-BES) with a 1-month dual antiplatelet therapy (DAPT) in high bleeding risk (HBR) patients. This is the first study comparing outcomes for a 1-month versus longer DAPT strategies following PF-BES-percutaneous coronary intervention (PCI).

METHODS

All patients undergoing PF-BES-PCI (January 2016 to July 2018) were included in the multicenter CHANCE registry. Patients were stratified according to DAPT strategy at discharge (planned 1-month vs. planned >1-month). Primary outcomes were the 390-day estimates of a patient-oriented and of a device-oriented composite endpoints (POCE: death, myocardial infarction [MI] or target vessel revascularization; DOCE: cardiac death, target vessel-MI or ischemia-driven target lesion revascularization). Landmark analyses from 1-month post-PCI were carried.

RESULTS

Following PF-BES-PCI, 328(40.3%) and 485(59.6%) patients were discharged with 1-month and longer DAPT (12 months [6-12]), respectively. Patients with a previous or index MI were less likely to be discharged on 1-month DAPT. Patients prescribed with 1-month DAPT were more likely to be at HBR than those with longer DAPT (90.2% vs. 69.9%, p = .001). No between-groups differences in the primary outcomes (planned 1-month vs. planned >1-month DAPT: POCE 11.9% vs. 13.2%, p = .747; DOCE: 4.8% vs. 8.1%, p = .500) were observed, also after adjusting for confoundings (POCE: adjusted-hazard ratio [adj-HR] 1.26, 95%CI 0.74-2.13; DOCE: adj-HR 1.00, 95%CI 0.49-1.99). Landmark analyses showed similar results.

CONCLUSIONS

In a large all-comers registry of PF-BES PCI, no interaction of planned DAPT strategy (1-month vs. >1-month) with outcomes was found. This observation warrants investigation in adequately powered randomized studies (ClinicalTrials.gov NCT03622203).

RhoA inhibitor-eluting stent attenuates restenosis by inhibiting YAP signaling

OBJECTIVE

Current drug-eluting stent (DES) treatment is promising, but it still has the drawback of in-stent restenosis, which remains a clinically relevant problem. Efforts should be made to discover new signaling molecules and novel potential targets for the prevention of arterial restenosis. In this study, we fabricated a novel DES targeting the RhoA pathway and further examined this promising strategy in vitro and in a rabbit carotid model.

METHODS

Active RhoA expression is correlated with the synthetic smooth muscle phenotype, and the RhoA inhibitor rhosin suppresses this phenotypic modulation at both transcriptional and translational levels. We further demonstrated that the RhoA inhibitor rhosin might act through the YAP pathway in smooth muscle cell phenotype modulation by a gain-of-function assay. Moreover, we fabricated a RhoA inhibitor-eluting stent and tested it in a rabbit carotid model.

RESULTS

Compared with a bare-metal stent, the RhoA inhibitor-eluting stent significantly attenuated neointimal formation at 6 months. However, overexpression of YAP by lentivirus blocked the antirestenosis effect of the RhoA inhibitor-eluting stent and repressed smooth muscle-specific genes.

CONCLUSIONS

RhoA inhibitor-eluting stents attenuate neointimal formation through inhibition of the YAP signaling pathway. This novel DES may represent a potential strategy for the treatment of in-stent restenosis.

Materials and Devices for Biodegradable and Soft Biomedical Electronics

Biodegradable and soft biomedical electronics that eliminate secondary surgery and ensure intimate contact with soft biological tissues of the human body are of growing interest, due to their emerging applications in high-quality healthcare monitoring and effective disease treatments. Recent systematic studies have significantly expanded the biodegradable electronic materials database, and various novel transient systems have been proposed. Biodegradable materials with soft properties and integration schemes of flexible or/and stretchable platforms will further advance electronic systems that match the properties of biological systems, providing an important step along the path towards clinical trials. This review focuses on recent progress and achievements in biodegradable and soft electronics for biomedical applications. The available biodegradable materials in their soft formats, the associated novel fabrication schemes, the device layouts, and the functionality of a variety of fully bioresorbable and soft devices, are reviewed. Finally, the key challenges and possible future directions of biodegradable and soft electronics are provided.

Mitoxantrone suppresses vascular smooth muscle cell (VSMC) proliferation and balloon injury-induced neointima formation: An in vitro and in vivo study

Neointima formation, which occurs after vascular injury due to vascular disease or interventions such as angioplasty and stent placement, is a complex process that involves multiple molecular and cellular mechanisms. The inhibition of neointima formation is vital to prevent restenosis of blood vessels. In the present study, we investigated whether the systemic administration of mitoxantrone can inhibit neointima formation, and evaluated the underlying mechanisms under in vitro and in vivo experimental conditions. In vitro, rat and human vascular smooth muscle cells (RVSMCs and HVSMCs) were stimulated with platelet-derived growth factor-BB (PDGF-BB) and treated with mitoxantrone or DMSO as a control. In vivo, 54 male Sprague-Dawley rats were subjected to carotid artery balloon injury and then intravenously administered with mitoxantrone. Cell proliferation was determined using the CCK-8 assay. Cell cycle analysis was performed using flow cytometry, and protein expression was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. We used monoclonal mouse anti-bromodeoxyuridine (BrdU) antibody for the detection of BrdU and anti-Topoisomerase II antibody for staining Type II topoisomerase (Topo II), one week after the ballon injury. In both RVSMCs and HVSMCs, mitoxantrone treatment induced Topo II degradation, as well as suppressed DNA replication, cell cycle progression, and VSMC proliferation. A reduction in intimal hyperplasia, intimal-to-medial area ratio, and Topo II level was observed in mitoxantrone-treated rats, as compared to the control (saline) group. Overall, our results indicate that systemic administration of mitoxantrone can reduce neointimal hyperplasia and, thus, represents a suitable option for restenosis treatment.

Early Clinical Experience with a Polymer-Free Biolimus A9 Drug-Coated Stent in DES-Type Patients Who Are Poor Candidates for Prolonged Dual Anti-Platelet Therapy

INTRODUCTION

Prolonged dual anti-platelet therapy (DAPT) may cause excess bleeding in certain patients. The biolimus-A9 drug-coated stent (BA9-DCS) has a rapid drug-elution profile allowing shortened DAPT. Data were gathered on the early experience implanting this stent in drug-eluting stent eligible patients deemed to be at high risk of bleeding.

BACKGROUND AND METHODS

The demographics, procedural data and clinical outcomes were gathered prospectively for 249 patients treated with a BA9-DCS stent at 2 UK centres, and compared to a cohort of patients treated in the same period with drug-eluting stents (PCI-DES).

RESULTS

Operator-defined BA9-DCS indications included warfarin therapy, age, and anaemia. Patients receiving a BA9-DCS were older (71.6±11.8 vs. 64.8±11.6yrs, p<0.001), more often female (38.2 vs. 26.8%, P<0.001), and more likely to have comorbidity including chronic kidney disease or poor LV function than PCI-DES patients. The baseline Mehran bleed risk score was also significantly higher in the BA9-DCS group (19.4±8.7 vs. 13.1±5.8, p<0.001). Of the BA9-DCS cohort, 95.5% of patients demonstrated disease fitting NICE criteria for DES placement. The number of lesions treated (1.81±1.1 vs. 1.58±0.92, p = 0.003), total lesion length (32.1±21.7 vs. 26.1±17.6mm, p<0.001), number of stents used (1.93±1.11 vs. 1.65±1.4, p = 0.007) and total stent length (37.5±20.8 vs. 32.4±20.3, p<0.01) were greater for BA9-DCS patients. DAPT was prescribed for 3.3±3.9 months for BA9-DCS patients and 11.3±2.4 months for PCI-DES patients (p<0.001). At follow up of 392±124 days despite the abbreviated DAPT course stent related event were infrequent with ischemia-driven restenosis PCI (2.8 vs. 3.4%, p = 0.838), and stent thrombosis (1.6 vs. 2.1%, p = 0.265) rates similar between the BA9-DCS ad PCI-DES groups. After propensity scoring all clinical end-points were similar between both cohorts.

CONCLUSIONS

This early experience using polymer-free BA9 drug-coated stents in drug-eluting stent type patients at risk of bleeding are encouraging. Further studies are warranted.

A new polymer-free drug-eluting stent with nanocarriers eluting sirolimus from stent-plus-balloon compared with bare-metal stent and with biolimus A9 eluting stent in porcine coronary arteries

BACKGROUND

Permanent polymers in first generation drug-eluting stent (DES) have been imputed to be a possible cause of persistent inflammation, remodeling, malapposition and late stent thrombosis. We aim to describe the in vivo experimental result of a new polymer-free DES eluting sirolimus from stent-plus-balloon (Focus np stent, Envision Scientific) compared with a bare-metal stent (BMS) (Amazonia CroCo, Minvasys) and with a biolimus A9 eluting stent (Biomatrix, Biosensors).

METHODS

In 10 juvenile pigs, 23 coronary stents were implanted in the coronary arteries (8 Amazonia CroCo, 8 Focus np, and 7 Biomatrix). At 28-day follow-up, optical coherence tomography (OCT) and histology were used to evaluate neointimal hyperplasia and healing response.

RESULTS

According to OCT analysis, Focus np stents had a greater lumen area and less neointimal hyperplasia response than BMS and Biomatrix had. Histomorphometry results showed less neointimal hyperplasia in Focus np than in BMS. Histology showed a higher fibrin deposition in Biomatrix stent compared to Focus np and BMS.

CONCLUSIONS

The new polymer-free DES with sirolimus eluted from stent-plus-balloon demonstrated safety and reduced neointimal proliferation compared with the BMS and Biomatrix stents at 28-day follow-up in this porcine coronary model. This new polymer-free DES is promising and warrants further clinical studies.

Comparison of 3 biodegradable polymer and durable polymer-based drug-eluting stents in all-comers (BIO-RESORT): rationale and study design of the randomized TWENTE III multicenter trial

AIM

To evaluate the safety and efficacy of 2 novel drug-eluting stents (DES) with biodegradable polymer-based coatings versus a durable coating DES.

METHODS AND RESULTS

BIO-RESORT is an investigator-initiated, prospective, patient-blinded, randomized multicenter trial in 3540 Dutch all-comers with various clinical syndromes, requiring percutaneous coronary interventions (PCI) with DES implantation. Randomization (stratified for diabetes mellitus) is being performed in a 1:1:1 ratio between ORSIRO sirolimus-eluting stent with circumferential biodegradable coating, SYNERGY everolimus-eluting stent with abluminal biodegradable coating, and RESOLUTE INTEGRITY zotarolimus-eluting stent with durable coating. The primary endpoint is the incidence of the composite endpoint target vessel failure at 1 year, consisting of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. Power calculation assumes a target vessel failure rate of 8.5% with a 3.5% non-inferiority margin, giving the study a power of 85% (α level .025 adjusted for multiple testing). The impact of diabetes mellitus on post-PCI outcome will be evaluated. The first patient was enrolled on December 21, 2012.

CONCLUSIONS

BIO-RESORT is a large, prospective, randomized, multicenter trial with three arms, comparing two DES with biodegradable coatings versus a reference DES with a durable coating in 3540 all-comers. The trial will provide novel insights into the clinical outcome of modern DES and will address the impact of known and so far undetected diabetes mellitus on post-PCI outcome.

A randomised comparison of a novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent with a durable polymer everolimus-eluting stent: clinical and angiographic follow-up of the TARGET I trial

AIMS

The study sought to evaluate the safety and efficacy of FIREHAWK, a novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent (SES) for treating patients with single de novo coronary lesions compared with the durable polymer everolimus-eluting stent (EES) XIENCE V.

METHODS AND RESULTS

A total of 458 patients with single de novo native coronary lesions ≤24 mm in length and a coronary artery ≥2.25 to ≤4.0 mm in diameter were enrolled in the TARGET I study, a prospective, randomised, non-inferiority trial. The primary endpoint was in-stent late lumen loss (LLL) at nine-month follow-up. The secondary endpoint, target lesion failure (TLF), was defined as the composite of cardiac death, target vessel myocardial infarction (TVMI), or ischaemia-driven target lesion revascularisation (iTLR). Patients were centrally randomised to treatment with either biodegradable polymer SES (n=227) or durable polymer EES (n=231). The nine-month in-stent LLL of the biodegradable polymer SES was comparable to the EES group (0.13 ± 0.24 mm vs. 0.13 ± 0.18 mm, p=0.94; difference and 95% confidence interval 0.00 [-0.04, 0.04] mm; p for non-inferiority <0.0001). Cardiac death (0.4% vs. 0.0%), TVMI (1.3% vs. 1.7%), iTLR (0.4% vs. 0.4%) and TLF (2.2% vs. 2.2%) were similar between the biodegradable polymer SES and durable polymer EES groups at 12-month follow-up (all p>0.05). No definite/probable stent thrombosis was observed in both of these groups.

CONCLUSIONS

In the multicentre TARGET I trial, the novel abluminal groove-filled biodegradable polymer SES FIREHAWK was non-inferior to the durable polymer EES XIENCE V with respect to the primary endpoint of in-stent LLL at nine months for treating patients with single de novo coronary lesions. The incidences of clinical endpoints were low in both of the stents at 12-month follow-up. (ClinicalTrials.gov identifier: NCT01196819).