Before coronary angioplasty is done, your doctor will need to know the location and extent of the blockages in your coronary (heart) arteries. To find this information, your doctor will use coronary angiography (an-jee-OG-ra-fee). This test uses dye and special x rays to show the insides of your arteries.
During angiography, a small tube (or tubes) called a catheter is inserted in an artery, usually in the groin (upper thigh). The catheter is threaded to the coronary arteries.
Special dye, which can be seen on an x ray, is injected through the catheter. X-ray pictures are taken as the dye flows through your coronary arteries. This outlines blockages, if any are present, and tells your doctor the location and extent of the blockages.
For the angioplasty procedure, another catheter with a balloon on its tip (a balloon catheter) is inserted in the coronary artery and positioned in the blockage. The balloon is then expanded. This pushes the plaque against the artery wall, relieving the blockage and improving blood flow.
Coronary Balloon Angioplasty
The illustration shows a cross-section of a coronary artery with plaque buildup. The coronary artery is located on the surface of the heart. Figure A shows the deflated balloon catheter inserted into the narrowed coronary artery. In figure B, the balloon is inflated, compressing the plaque and restoring the size of the artery. Figure C shows the widened artery.
A small mesh tube called a stent usually is placed in the artery during angioplasty. The stent is wrapped around the deflated balloon catheter before the catheter is inserted in the artery.
When the balloon is inflated to compress the plaque, the stent expands and attaches to the artery wall. The stent supports the inner artery wall and reduces the chance of the artery becoming narrowed or blocked again.
Some stents are coated with medicines that are slowly and continuously released into the artery. These are called drug-eluting stents. The medicines help prevent the artery from becoming blocked with scar tissue that grows in the artery.
Angioplasty With Stent Placement
The illustration shows the placement of a stent in a coronary artery with plaque buildup. Figure A shows the deflated balloon catheter and closed stent inserted into the narrowed coronary artery; the inset image shows a cross-section of the artery. In figure B, the balloon is inflated, expanding the stent and compressing the plaque. Figure C shows the stent-widened artery; the inset image shows a cross-section of the artery.
Image source: Getty