Long-Term Outcomes Following Sirolimus-Coated Balloon or Drug-Eluting Stents for Treatment of In-Stent Restenosis

Innovations in Vascular Repair from Mechanical Intervention to Regenerative Therapies

BACKGROUND

Vascular diseases, including atherosclerosis and thrombosis, are leading causes of morbidity and mortality worldwide, often resulting in vessel stenosis that impairs blood flow and leads to severe clinical outcomes. Traditional mechanical interventions, such as balloon angioplasty and bare-metal stents, provided initial solutions but were limited by restenosis and thrombosis. The advent of drug-eluting stents improved short-term outcomes by inhibiting vascular smooth muscle cell proliferation, however, they faced challenges including delayed reendothelialization and late-stage thrombosis.

METHODS

This review highlights the progression from mechanical to biological interventions in treating vascular stenosis and underscores the need for integrated approaches that combine mechanical precision with regenerative therapies.

RESULTS

To address long-term complications, bioresorbable stents were developed to provide temporary scaffolding that gradually dissolves, yet they still encounter challenges with mechanical integrity and optimal degradation rates. Consequently, emerging therapies now focus on biological approaches, such as gene therapy, extracellular vesicle treatments, and cell therapies, that aim to promote vascular repair at the cellular level. These strategies offer the potential for true vascular regeneration by enhancing endothelialization, modulating immune responses, and stimulating angiogenesis.

CONCLUSION

Integrating mechanical precision with regenerative biological therapies offers a promising future for treating vascular stenosis. A comprehensive approach combining these modalities could achieve sustainable vascular health.

Expanding indications for drug-coated balloons in coronary artery disease

INTRODUCTION

Despite technical advances in percutaneous coronary intervention (PCI) and new iterations of drug-eluting stents (DES), complications still occur, including stent thrombosis and in-stent restenosis (ISR). Drug-coated balloons (DCBs) provide a promising option for the treatment of coronary lesions - particularly when DES are undesirable or contraindicated - allowing for PCI without the implantation of metallic devices, thus adhering to the 'leave nothing behind' principle.

AREAS COVERED

A comprehensive literature search has been performed on PubMed, Web of Science and Cochrane, up to November 2024, with no significant restrictions. This article provides an overview of available DCB and summarizes the evidence supporting their use in different settings, including ISR, small-vessel disease, de novo large-vessel disease, and bifurcations.

EXPERT OPINION

Trials of DCB are heterogeneous with respect to population, sample size, follow-up, anatomical pattern, and device used. Furthermore, they usually have limited statistical power for clinical endpoints. Based on current knowledge, DES may be preferrable for DES-ISR, de novo lesions in large vessels and for the treatment of the main branch in true bifurcations, with DCB approved for small-vessel disease and selected ISR lesions. Ongoing trials are expected to provide definitive insights into the efficacy and safety of DCB in different scenarios.