Device profile of the Resolute Onyx Zotarolimus eluting coronary stent system for the treatment of coronary artery disease: overview of its safety and efficacy

The resolute Onyx in TIA management (ROTIA)

BACKGROUND

First-line treatment for symptomatic intracranial atherosclerotic disease (ICAD) is medical management; however, interventional approaches are increasingly considered for refractory disease. The Resolute Onyx in TIA management (ROTIA) study is a post-market evaluation of the Resolute Onyx (R-Onyx) drug-eluting stent in the treatment of recurrent transient ischemic attacks (TIAs) due to refractory ICAD (off-label use).

METHODS

This is a single-center, retrospective case series of consecutive patients who underwent angioplasty and stenting with R-Onyx for treatment of recurrent TIAs due to refractory ICAD from October 2019 to November 2022. Included patients were ages 22-80, had a baseline modified Rankin Scale of ≤2, and had recurrent TIAs attributed to intracranial artery stenosis >70% despite maximal medical therapy. Primary outcomes of interest were peri-procedural complications (TIA, stroke, intracranial hemorrhage, mortality) up to 72 h post-stenting and ischemic stroke up to 18 months post-stenting.

RESULTS

Twenty patients (mean age 66.84 ± 14; 25% female; 80% Hispanic) were included. A total of 21 stents were successfully deployed with no peri-procedural complications. There were no recurrent ischemic events at 30 days post-stenting. At 18 months post-stenting, there were no ischemic events and no patient exhibited in-stent restenosis.

CONCLUSION

ROTIA demonstrates the feasibility of using the Resolute Onyx drug-eluting stent for the management of TIAs due to refractory ICAD, with high technical success and low peri-procedural complications. Limitations include the retrospective and single-center nature of this study. Future prospective, multi-center, randomized trials with extended observation periods are needed.

The resolute Onyx drug eluting stent for neurointervention: A technical series

INTRODUCTION

Current methods for angioplasty and stenting of the intracranial vasculature for neurointervention are limited. The Wingspan Stent System is Food and Drug Administration (FDA) approved with human device exemption for a limited patient group and despite numerous prospective registries and trials demonstrating reasonable safety, still carries warnings from the FDA for its use. Given these limitations, we present the technical nuances and outcomes of the off-label use of the Resolute Onyx drug-eluting stent (DES) for neurointerventional purposes.

METHODS

Retrospective chart review of all patients undergoing a neurointerventional procedure with the Resolute Onyx DES was done from January 2017-2021. The Resolute Onyx is a coronary balloon-mounted drug-eluting (zotarolimus) single wire laser cut stent. Technical details and procedural outcomes were collected.

RESULTS

In total 40 patients had attempted placement of the Resolute Onyx DES with procedural success in 95% of patients. The most common vessel stented was the basilar artery, 30% (12/40). The most common indication was intracranial atherosclerotic disease in 62.5% (25/40) patients, followed by acute stroke in 17.5% (7/40) of patients. The technical and procedural outcomes were excellent with only one technical complication (2.5%).

CONCLUSIONS

This series describes the initial technical safety and utility of utilizing a new generation balloon-mounted drug-eluting stent for neurointerventional purposes. This stent offers the potential for improved navigability, delivery, and outcomes compared to current neurointerventional options and warrants further study.

Drug-Eluting, Bioresorbable Cardiovascular Stents─Challenges and Perspectives

Globally, the leading causes of natural death are attributed to coronary heart disease and type 1 and type 2 diabetes. High blood pressure levels, high cholesterol levels, smoking, and poor eating habits lead to the agglomeration of plaque in the arteries, reducing the blood flow. The implantation of devices used to unclog vessels, known as stents, sometimes results in a lack of irrigation due to the excessive proliferation of endothelial tissue within the blood vessels and is known as restenosis. The use of drug-eluting stents (DESs) to deliver antiproliferative drugs has led to the development of different encapsulation techniques. However, due to the potency of the drugs used in the initial stent designs, a chronic inflammatory reaction of the arterial wall known as thrombosis can cause a myocardial infarction (MI). One of the most promising drugs to reduce this risk is everolimus, which can be encapsulated in lipid systems for controlled release directly into the artery. This review aims to discuss the current status of stent design, fabrication, and functionalization. Variables such as the mechanical properties, metals and their alloys, drug encapsulation and controlled elution, and stent degradation are also addressed. Additionally, this review covers the use of polymeric surface coatings on stents and the recent advances in layer-by-layer coating and drug delivery. The advances in nanoencapsulation techniques such as liposomes and micro- and nanoemulsions and their functionalization in bioresorbable, drug-eluting stents are also highlighted.

Evolution of drug-eluting coronary stents: a back-and-forth journey from the bench-to-bedside

Coronary stents have revolutionized the treatment of coronary artery disease. Compared with balloon angioplasty, bare-metal stents effectively prevented abrupt vessel closure but were limited by in-stent restenosis due to smooth muscle cell proliferation and neointimal hyperplasia. The first-generation drug-eluting stent (DES), with its antiproliferative drug coating, offered substantial advantages over bare-metal stents as it mitigated the risk of in-stent restenosis. Nonetheless, they had several design limitations that increased the risk of late stent thrombosis. Significant advances in stent design, including thinner struts, enhanced polymers' formulation, and more potent antiproliferative agents, have led to the introduction of new-generation DES with a superior safety profile. Cardiologists have over 20 different DES types to choose from, each with its unique features and characteristics. This review highlights the evolution of stent design and summarizes the clinical data on the different stent types. We conclude by discussing the clinical implications of stent design in high-risk subsets of patients.

Effects of Simulated COVID-19 Cytokine Storm on Stent Thrombogenicity

BACKGROUND

Cytokine storm-related hypercoagulation may be important in the pathogenesis of stent thrombosis in patients with SARS-CoV-2. Whether stent polymers behave differently under such conditions has never been explored.

METHODS

Fluorinated polymer-nanocoated and uncoated COBRA stents (CeloNova), BioLinx-polymer-coated Resolute Onyx stents (Medtronic), and Synergy stents (Boston Scientific), which are abluminally coated with a bioabsorbable polymer, were exposed to human blood from healthy donors which was supplemented with 400 pg/mL IL-6 and 100 pg/mL TNF-α, similar to what is seen in cytokine storm caused by SARS-CoV-2. Platelet adhesion and neutrophil activation, assessed by immunofluorescence, were compared under cytokine storm and control conditions (untreated blood) (n = 4 experimental runs).

RESULTS

Platelet adhesion values, defined as %platelet-covered area x staining intensity, were significantly lower in coated and uncoated COBRA and in Resolute Onyx than in Synergy under control conditions (1.28 × 107 ± 0.43 × 107 vs. 2.92 × 107 ± 0.49 × 107 vs. 3.57 × 107 ± 0.73 × 107 vs. 9.94 × 107 ± 0.99 × 107; p ≤0.0001). In cytokine storm, platelet adhesion values remained low in coated COBRA-PzF (1.78 × 107 ± 0.38 × 107) compared to all other devices (uncoated COBRA: 5.92 × 107 ± 0.96 × 107; Resolute Onyx: 7.27 × 107 ± 1.82 × 107; Synergy: 11.28 × 107 ± 1.08 × 107; p ≤ 0.0001). Although cytokine storm conditions significantly increased neutrophil activation in all stents, it was significantly less in coated and uncoated COBRA, and in Resolute Onyx than in Synergy.

CONCLUSIONS

Blood-biomaterials interactions may determine the thrombogenic potential of stents. Under simulated cytokine storm conditions, fluoropolymer-coated stents showed the most favorable anti-thrombogenic and anti-inflammatory properties.