Percutaneous Coronary Intervention

Percutaneous coronary intervention (PCI) is a procedure that opens a narrowed or blocked artery supplying blood to the heart muscle, without open-heart surgery. A thin tube called a catheter carries a balloon to the narrowed segment; inflating the balloon widens the passage, and a stent is usually inserted to help keep it open.

Why the artery needs widening

The coronary arteries supply oxygen-rich blood to the heart muscle. In atherosclerosis, fatty deposits called plaque build up in the artery wall and narrow its inner passage, or lumen. This can limit oxygen delivery, particularly when the heart works harder, causing chest discomfort called angina.

• If a plaque ruptures, a blood clot can form and suddenly obstruct blood flow, potentially causing a heart attack.
• PCI restores flow by enlarging the passage at the obstruction rather than creating a new route around it.

How the procedure restores blood flow

PCI uses instruments introduced through a small puncture in an artery, usually at the wrist or groin. The operator guides them to the coronary artery using X-ray imaging.

• Coronary angiography uses injected contrast material to show the coronary arteries on X-ray images and identify the narrowed segment.
• A thin guidewire is passed across the narrowing, allowing a catheter carrying a deflated balloon to reach the affected site.
• During balloon angioplasty, inflation compresses plaque against the artery wall and stretches the narrowed segment, increasing the space available for blood flow.
• The balloon is deflated and withdrawn after the artery has been widened; it does not remain inside the artery.

How a stent helps maintain the opening

A stent is a small mesh tube usually expanded at the narrowed site by the balloon. It remains inside the artery as a scaffold, helping prevent the treated segment from recoiling or closing again.

• Drug-eluting stents release medicine that reduces excessive tissue growth within the treated segment and lowers the risk of re-narrowing, called restenosis.
• Antiplatelet medicines are prescribed to reduce the risk of a clot forming inside the stent.
• PCI treats a particular obstruction but does not cure the underlying atherosclerosis; medicines and risk-factor control remain important.
• Not every coronary narrowing requires PCI; treatment depends on symptoms, the pattern of disease and the clinical situation.