What Are the Risks of Having a Stent?

Risks Related to Angioplasty

Any medical procedure has risks, but major complications from angioplasty are rare. The most common risks from angioplasty include:

• Bleeding from the site where the catheter was inserted into the skin
• Damage to the blood vessel from the catheter
• Infection
• Allergic reaction to the dye used during the procedure

Another common problem after angioplasty is too much tissue growth within the treated portion of the artery. This can cause the artery to narrow or close again, which is called restenosis. This problem is often avoided with the use of newer stents coated with medicines that help prevent too much tissue growth. Treating the tissue around the stent with radiation also can prevent tissue growth. For this procedure, the doctor puts a wire through a catheter to where the stent is placed. The wire releases radiation and stops cells around the stent from growing and blocking the artery.

Restenosis of a Stent-Widened Coronary Artery

The illustration shows the restenosis of a stent-widened coronary artery. The coronary artery is located on the surface of the heart. In figure A, the expanded stent compresses plaque, allowing normal blood flow. The inset image on figure A shows a cross-section of the compressed plaque and stent-widened artery. In figure B, over time, the plaque grows through and around the stent, causing a partial blockage and abnormal blood flow. The inset image on figure B shows a cross-section of the growth of the plaque around the stent.

Risks Related to Stent

About 1 to 2 percent of people with a stented artery develop a blood clot at the stent site. Blood clots can cause heart attacks, strokes, or other serious problems. The risk of blood clots is greatest during the first few months after the stent is placed in the artery. Your doctor will probably have you take blood-thinning or anticlotting medicines for at least a few months after having a stent procedure to prevent blood clots.

Stents coated with medicine (drug-releasing stents), which are often used to keep clogged heart arteries open, may increase your risk for potentially dangerous blood clots. But an expert Food and Drug Administration panel found no conclusive evidence that these stents increase the chances of having a heart attack or dying, if used as recommended. Patients with drug-releasing stents are usually advised to take aspirin and an anticlotting drug, such as clopidogrel, for months to years to lower the risk of blood clots.

Risks Related to Aortic Stents in the Abdomen

Whenever an aneurysm in the abdomen region of the aorta is repaired with either surgery or with a fabric stent, few rare but serious complications can occur, including:

• A burst artery (aneurysm rupture).
• Blocked blood flow to the stomach or lower body.
• Paralysis in the legs due to interruption of blood flow to the spinal cord. This is an especially rare complication.

Another possible complication is the fabric stent moving further down the aorta. This sometimes happens years after the stent is first placed. Such stent movement may require a doctor to place another fabric stent in the area of the aneurysm.