PTCA, or percutaneous transluminal coronary angioplasty, is a minimally invasive procedure that opens blocked coronary arteries to improve blood flow to the heart muscle.

First, a local anesthesia numbs the groin area. Then, the doctor puts a needle into the femoral artery, the artery that runs down the leg. The doctor inserts a guide wire through the needle, removes the needle, and replaces it with an introducer, an instrument with two ports for inserting flexible devices. Then the original guide wire is replaced by a thinner wire. The doctor passes a long narrow tube called a diagnostic catheter over the new wire, through the introducer, and into the artery. Once it's in, the doctor guides it to the aorta and removes the guide wire.

With the catheter at the opening of a coronary artery, the doctor injects dye and takes an X-ray.

If it shows a treatable blockage, the doctor backs the catheter out and replaces it with a guiding catheter, before removing the wire.

An even thinner wire is inserted and guided across the blockage. A balloon catheter is then guided to the blockage site. The balloon is inflated for a few seconds to compress the blockage against the artery wall. Then it's deflated. The doctor may inflate the balloon a few more times, each time filling it a little more to widen the passage.

This may then be repeated at each blocked or narrowed site.

The doctor may also place a stent, a latticed metal scaffold, within the coronary artery to keep it open.

Once the compression is done, dye is injected and an X-ray is taken to check for changes in the arteries.

Then the catheter is removed and the procedure is complete.