Stent insertion is a minimally invasive procedure where a cardiologist threads a thin, flexible tube through an artery to reach a blocked blood vessel in your heart, then expands a small metal mesh tube to hold that vessel open. The whole process typically takes 30 minutes to two hours, and most people are awake the entire time.
How You’re Prepared and Sedated
Stent placement does not require general anesthesia. You receive what’s called conscious sedation: a combination of medications through an IV that makes you drowsy and relaxed but still able to respond to the medical team. The access site on your wrist or groin is numbed with a local anesthetic so you won’t feel the initial needle insertion. Music, verbal reassurance, and liberal use of local numbing agents can reduce how much sedation you actually need. For patients who are difficult to sedate safely, such as those with severe sleep apnea or morbid obesity, an anesthesiologist may provide deeper sedation.
Where the Catheter Enters Your Body
The cardiologist accesses your arterial system through one of two sites: the radial artery in your wrist or the femoral artery in your groin. Current guidelines recommend wrist access for all stent procedures, and about 61% of cases now use this approach. Wrist access became the dominant method starting around 2016, largely because it carries a lower risk of major bleeding at the insertion site (0.4% versus 0.8% for groin access) and allows you to sit up and move around sooner afterward.
Groin access is still used in roughly 39% of cases, particularly when the procedure is more complex or the arteries in the wrist are too small. Long-term survival rates are the same regardless of which access point is used.
The Step-by-Step Insertion Process
Once the access site is numbed, the cardiologist inserts a needle into the artery. A thin, flexible wire called a guidewire is threaded through the needle, and then the needle is removed. A short plastic tube called a sheath is slid over the guidewire and left in place to keep the artery open and serve as an entry port for the tools that follow.
Through this sheath, the cardiologist advances a longer, hollow catheter up through your arterial system toward your heart. To see where the catheter is going, the team uses fluoroscopy, which is essentially a real-time X-ray video. A contrast dye is injected through the catheter into your coronary arteries, making the blood flow visible on a screen. This reveals exactly where blockages are and how severe they are.
Once the blockage is located, a very thin guidewire is threaded through the catheter and carefully navigated past the narrowed section. This wire acts as a rail. A second, specialized catheter carrying the stent is slid over this guidewire and positioned precisely at the blockage. The stent sits crimped tightly around a small balloon at the tip of this catheter.
When the cardiologist confirms the positioning on the fluoroscopy screen, the balloon is inflated. This does two things simultaneously: it compresses the plaque against the artery wall and expands the metal stent into its permanent open shape. The balloon is then deflated and withdrawn, leaving the stent locked in place as a permanent scaffold holding the artery open.
What the Stent Is Made Of
Modern coronary stents are made from metal alloys, most commonly cobalt-chromium. Some use platinum-chromium or cobalt-nickel alloys instead, depending on the specific design. These metals are chosen because they’re strong enough to hold an artery open while being thin enough to navigate through blood vessels.
Nearly all stents placed today are drug-eluting, meaning they’re coated with a medication that slowly releases over weeks to months. These drugs belong to a family that suppresses the overgrowth of tissue inside the stent, which is the main reason stents used to re-narrow over time. Bare-metal stents without this coating are rarely used now because they carry a higher risk of that re-narrowing.
What You Feel During the Procedure
You won’t feel the catheter traveling through your arteries because the interior walls of blood vessels don’t have pain-sensing nerves. You may feel brief pressure or a warm flushing sensation when the contrast dye is injected. When the balloon inflates to deploy the stent, some people experience a few seconds of chest tightness or mild chest pain as blood flow is temporarily interrupted. This passes quickly once the balloon deflates. The sedation keeps you comfortable, and the team communicates with you throughout.
Recovery After the Procedure
How long you stay in the hospital depends on why you needed the stent. If the procedure was planned (elective), you may go home the same day or the next morning. If the stent was placed during an emergency like a heart attack, the stay is longer.
At the access site, pressure is applied after the sheath is removed to prevent bleeding. If the catheter went through your wrist, a compression band is typically placed and gradually loosened over a few hours. Groin access requires you to lie flat for a period while the artery seals. You should avoid strenuous exercise and heavy lifting for at least 24 hours.
After discharge, you’ll take two blood-thinning medications simultaneously for a period. The current standard for patients who received a stent after a heart attack or unstable chest pain is at least 12 months of this dual therapy. Some newer approaches allow one of the two medications to be stopped after one to three months in patients who have a high risk of bleeding, with the remaining medication continued for the full year. Stopping these medications too early is one of the main risk factors for a blood clot forming inside the stent.
Risks and Complication Rates
Stent placement is one of the most commonly performed heart procedures, and serious complications are uncommon. The most concerning risk is stent thrombosis, where a blood clot forms inside the stent and blocks it. This occurs in about 0.7% of patients within the first year, dropping to 0.2% to 0.6% per year after that. The risk is higher, up to 3.4%, when the stent is placed during an acute heart attack rather than as a planned procedure.
Re-narrowing inside the stent, called in-stent restenosis, affects about 10% of patients. In a quarter of those cases, the re-narrowing is severe enough to cause a heart attack. This is far less common with drug-eluting stents than it was with older bare-metal designs. Bleeding at the access site is the most frequent minor complication, occurring in under 1% of wrist-access procedures.
Dissolving Stents: A Work in Progress
Researchers have been working on stents made from materials that gradually dissolve after the artery has healed, leaving no permanent metal behind. The first widely used version, a polymer-based scaffold called Absorb, was pulled from the market after trials showed higher rates of clotting and complications compared to standard metal stents. The scaffold’s thick structure and unpredictable breakdown were the main problems.
Newer designs using thinner materials, including magnesium-based metal scaffolds, have shown more promising results. One large registry of over 1,000 patients reported a clot rate of about 0.5% and procedural success of nearly 99% at one year. These devices currently require very precise implantation techniques and are limited to certain artery sizes (generally 2.75 mm or larger), so they’re not yet a routine option. They represent a potential next step, but for now, permanent drug-eluting metal stents remain the standard.