restenose

Restenose, also known as restenosis, is the re-narrowing of a blood vessel after it has been treated for stenosis. It most commonly occurs after percutaneous coronary intervention (PCI) with balloon angioplasty and stent placement, but can affect peripheral arteries and grafts as well. Restenosis results from neointimal hyperplasia and scar tissue growth within the vessel, leading to reduced lumen size and impaired blood flow. It typically develops within months of the initial procedure, though late occurrence is possible.

Stents influence restenosis risk. Bare-metal stents have higher rates of restenosis than drug-eluting stents, which release antiproliferative medications to limit neointimal growth. Restenosis within a previously placed stent is called in-stent restenosis (ISR). The likelihood of restenosis varies by vessel, lesion characteristics, and intervention type: historically, restenosis after balloon angioplasty could affect a large minority of patients, coronary bare-metal stents around a 20–30% risk, and drug-eluting stents reduce this risk to roughly 5–10% in the coronary circulation. Peripheral arteries and saphenous vein grafts may have different risk profiles and higher rates in some settings.

Clinical presentation ranges from recurrent chest pain (angina) or leg claudication to asymptomatic cases discovered on routine testing. Diagnosis is made with imaging, most commonly coronary angiography; intravascular imaging (IVUS or OCT) and duplex ultrasound are also used for assessment.

Management usually involves repeat revascularization, such as PCI with a newer stent or alternative techniques, along with medical optimization (antiplatelet therapy, lipid control, diabetes management, smoking cessation). Prevention focuses on device selection (favoring drug-eluting stents when appropriate) and aggressive risk-factor modification.