From the Guidelines
The most effective treatment option for restenosis due to neointimal hyperplasia is the use of drug-eluting stents (DES), particularly those containing everolimus, as they have been shown to result in lower rates of target-vessel restenosis and revascularization compared to other treatments. Treatment options for restenosis due to neointimal hyperplasia include both endovascular and surgical interventions. The primary approaches are:
- Repeat angioplasty with drug-coated balloons (DCBs)
- Implantation of drug-eluting stents (DES)
- Cutting balloon angioplasty
- Surgical bypass
According to the 2021 ACC/AHA/SCAI guideline for coronary artery revascularization 1, DES appears to provide the most benefit in treating restenosis, with everolimus-eluting stents showing the best efficacy. DCBs deliver antiproliferative medications like paclitaxel directly to the vessel wall to inhibit smooth muscle cell proliferation. For more severe cases, surgical options include bypass grafting using autologous veins or synthetic grafts to create a new pathway around the stenosed segment. Adjunctive medical therapy typically includes antiplatelet agents and statins, and risk factor modification. The choice between these options depends on the location and extent of restenosis, patient comorbidities, and previous interventions. Neointimal hyperplasia occurs due to vascular injury triggering smooth muscle cell migration and proliferation, so these treatments aim to either mechanically address the narrowing or pharmacologically inhibit the cellular processes driving restenosis.
In patients with recurrent episodes of restenosis despite repeat PCI with DES, or in patients who have diffuse ISR in large vessels or a complex presentation, CABG may be the preferred approach if the anatomy is suitable 1. Vascular brachytherapy is also a reasonable option in patients who already have multiple stent layers or have recurrent ISR with an artery that is unfavorable to receive another DES, and who are not good candidates for bypass surgery 1.
From the Research
Treatment Options for In-Stent Restenosis due to Neointimal Hyperplasia
- Treatment with balloon angioplasty is effective for focal in-stent restenotic lesions 2
- For other lesions, excimer laser, rotational atherectomy, and directional coronary atherectomy are associated with excellent initial outcome, but long-term outcome of these procedures is unclear 2
- Brachytherapy with both gamma and beta sources has been found to result in improved outcome with less angiographic restenosis and decreased target vessel revascularization 2
- Drug-eluting stents (DES) with biodegradable polymers and releasing paclitaxel or sirolimus can reduce neointimal hyperplasia and 1-year re-intervention compared to bare metal stents 3
- Sirolimus stents have been shown to be more effective than paclitaxel stents in reducing angiographic neointima 3
- Early short-term systemic use of sirolimus after bare-metal stenting can result in a significant reduction in in-stent restenosis and target lesion revascularization 4
- Intravascular ultrasound findings suggest that neointimal hyperplasia volume is significantly greater in paclitaxel-eluting stent restenoses than in sirolimus-eluting stent restenoses 5
Considerations for Treatment
- Late thrombosis has been documented in up to 10% of patients treated with vascular gamma brachytherapy, and increased stenosis at the edges of the treated segment is also seen 2
- Prolonged dual antiplatelet therapy and avoidance of a new stent has been shown to reduce late thrombosis in patients treated with vascular brachytherapy 2
- Stent underexpansion appears to be more common in sirolimus-eluting stents, while stent edge restenosis is more frequent in paclitaxel-eluting stents 5