A heart stent is a tiny mesh tube that holds open a narrowed coronary artery, restoring blood flow to the heart muscle. When fatty plaque builds up inside an artery and blocks 70% or more of the opening, the heart doesn’t get enough oxygen-rich blood. A stent compresses that plaque against the artery wall and acts as a permanent scaffold, keeping the vessel from collapsing or narrowing again.
How a Stent Restores Blood Flow
Coronary arteries can narrow over years as cholesterol and other deposits form plaque along their inner walls. When the narrowing becomes severe enough, it restricts blood flow and can cause chest pain, shortness of breath, or a heart attack. A stent addresses this by physically pushing the plaque flat against the artery wall and propping the vessel open.
The metal framework of the stent provides what engineers call radial strength: outward force that resists the artery’s tendency to spring back to its narrowed shape. This scaffolding also prevents loose bits of plaque from bulging into the bloodstream, which could trigger a clot. Modern stents are designed to hold the artery open while still allowing blood to reach smaller branch vessels along the way.
How the Procedure Works
Stent placement happens during a procedure called angioplasty. You’ll receive medicines to help you relax, but you’re typically awake the entire time. A doctor numbs a small area, usually at the wrist or groin, and makes a tiny cut to access a blood vessel. A thin, flexible tube called a catheter is threaded through that vessel all the way to the heart.
Dye is injected through the catheter so the narrowed artery shows up on X-ray. Then a second catheter, this one tipped with a tiny deflated balloon wrapped in a collapsed stent, is guided to the blockage. The balloon inflates, expanding the stent against the artery wall. Once the stent is locked in place, the balloon deflates and the catheters are removed. The whole process typically takes one to two hours.
When Stents Are Used
Stents are placed in two very different situations, and the urgency changes everything about the experience.
In a planned procedure, a stent is typically recommended when an artery is at least 70% to 80% blocked and symptoms like chest pain aren’t well controlled with medication alone. Your cardiologist identifies the blockage through imaging and schedules the angioplasty.
In an emergency, the goal is to reopen the artery during an active heart attack, when a clot has completely or nearly completely shut off blood flow. Without a stent, 10% to 15% of heart attack patients experience recurring blockage before they even leave the hospital. Research published in the New England Journal of Medicine found that placing a stent during a heart attack reduced the combined rate of death, repeat heart attack, stroke, or the need for another procedure from about 20% down to roughly 13% compared to balloon angioplasty alone. That improvement came almost entirely from fewer patients needing a second procedure to reopen the same artery.
Drug-Eluting vs. Bare-Metal Stents
The earliest stents were bare metal, essentially tiny wire cages made from stainless steel or similar alloys. They worked well at holding arteries open, but the body sometimes responded by growing new tissue over and through the stent, gradually re-narrowing the artery. This is called restenosis, and with bare-metal stents it happened in roughly 30% of cases.
Drug-eluting stents solved most of that problem. These stents are coated with a slow-release medication that discourages excess tissue growth. With modern second-generation drug-eluting stents, restenosis rates have dropped to about 12%, and in many patient groups the rate falls between 2% and 10%. The tradeoff is that because the drug slows healing of the artery lining, drug-eluting stents carry a slightly higher risk of blood clots forming on the stent itself. That’s why blood-thinning medication after the procedure is so important.
Today, drug-eluting stents are the standard choice for most patients. Bare-metal stents are still used in specific situations, such as when a patient can’t take blood thinners for an extended period.
Medication After Stent Placement
Getting a stent means committing to a medication regimen afterward. The most important part is dual antiplatelet therapy: two blood-thinning drugs taken together to prevent clots from forming on the new stent before the artery lining fully heals around it.
Current guidelines from the American College of Cardiology and American Heart Association recommend at least 12 months of dual antiplatelet therapy as the default for patients who received a stent after a heart attack or acute coronary event and who aren’t at high risk of bleeding. Your cardiologist may shorten or extend that timeline based on your individual bleeding risk and the reason you received the stent. Stopping these medications early, without your doctor’s guidance, is one of the most dangerous things you can do after getting a stent, because it dramatically raises the chance of a clot forming inside it.
Recovery and Getting Back to Normal
Recovery from stent placement is surprisingly quick compared to open-heart surgery. Most people go home the same day or the next morning. The catheter insertion site, whether at the wrist or groin, needs about a week to heal. During that week, you should avoid heavy lifting and strenuous physical activity.
You can typically drive again after one week. If you drive heavy vehicles professionally, you’ll need additional medical clearance, including an exercise stress test, before returning to work. Most people return to their normal routine, including moderate exercise, within a week or two, though your cardiologist will give you a personalized timeline based on how much heart damage occurred and how well the procedure went.
What Can Go Wrong
Stents are effective, but they’re not a permanent guarantee. The most common long-term issue is restenosis, where tissue gradually grows through the stent mesh and re-narrows the artery. With modern drug-eluting stents, this affects roughly 5% to 12% of patients depending on the complexity of the blockage and individual risk factors like diabetes. When it does happen, it can be treated with another stent or a specialized balloon.
Stent thrombosis, a sudden blood clot forming inside the stent, is rarer but more dangerous. It can cause a heart attack and is most likely to occur if antiplatelet medications are stopped too soon. The risk is highest in the first few months after placement and drops significantly once the artery wall has fully healed around the stent.
Dissolving Stents
Researchers have been working on bioresorbable stents, scaffolds made from materials that gradually dissolve in the body over one to three years. The idea is appealing: the stent holds the artery open during the critical healing period, then disappears, leaving behind a naturally functioning vessel with no permanent implant.
The first of these, Abbott’s Absorb scaffold, received FDA approval in 2016 but was pulled from the U.S. market just a year later due to higher-than-expected rates of clotting and treatment failure compared to conventional metal stents. As of 2023, six bioresorbable stents have European approval, made from materials ranging from plant-derived polymers to magnesium alloy, but none are currently available in the United States. The technology is still evolving, with newer designs using thinner struts and different materials to address the problems that sidelined the first generation.