The technique is also called PTCA or Percutaneous Transluminal Coronary Angioplasty. Angioplasty is a common medical procedure. It may be used to:
- Improve symptoms of CAD, such as angina and shortness of breath
- Reduce damage to the heart muscle from a heart attack. A heart attack occurs when blood flow through a coronary artery is completely blocked. Angioplasty is used during a heart attack to open the blockage and restore blood flow through the artery.
- Reduce the risk of death in some patients.
Prior to the procedure, the location and type of blockage plus the shape and size the coronary arteries have to be defined to help the cardiologist to decide on the appropriate treatment plan. Stenting, Atherectomy, medications or surgery are the other possible options.
Cardiac catheterization (Cath) is a specialized study of the heart during which a catheter or thin hollow flexible tube is inserted into the artery of the groin or arm. Under x-ray visualization, the tip of the catheter is guided to the heart. Pressures are measured and an X-Ray angiogram of the heart and blood vessels is obtained while iodine- containing colorless "dye" or contrast material is injected into the artery through a catheter. The iodinated solution blocks the passage of x-rays and causes the coronary arteries to be visualized during the procedure.
A sheath is introduced in a suitable vessel in the groin through which a long, flexible, soft plastic tube or guiding catheter is advanced and the tip positioned into the opening or mouth of the coronary artery. The tube measures approximately 2 to 3 mm in diameter. The direction of tip of the catheter is controlled by gently advancing and rotating the end of the catheter that sits outside the patient.
At the required position the x-ray imaging is done to estimate the size of the coronary artery and selects the type of balloon catheter and wire that will be used for the case. Heparin which is a "blood thinner" or medicine used to prevent the formation of clots is given. The guide wire which is an extremely thin wire with a flexible tip is inserted into through the catheter and into the coronary artery. The tip of the wire is then guided across the blockage and advanced beyond it. The tip of the balloon catheter is then passed over the guide wire and positioned across the lesion or blockage.
It is inflated by connecting it to a special handheld syringe pump using a mixture of saline and contrast material. The contrast material helps to visualize the balloon when it is inflated. The balloon catheter has metallic markers to know the location of the balloon.
Inflation is initially carried out at a pressure of 1 to 2 times that of the atmosphere and then gradually increased to 8 - 12 atmospheres or even higher. The balloon is kept inflated for 1 to 2 minutes and then deflated. Intermittent inflation allows blood flow through the artery during the time that the balloon is deflated. A nitroglycerin solution may be injected to prevent spasm of the artery. The inflation syringe has markers that are used to determine the pressure.
As the balloon is inflated, it compresses the atheroma and plaque that make up the coronary blockage. Unfortunately, the obstruction material of atherosclerosis is composed of soft fatty atheroma, firm plaque and a medium consistency mixture of the two. These materials resist expansion by a balloon in different ways. Soft material is compressed easily while firm matter compresses to a lesser degree and may demonstrate cracks following expansion by a balloon. Hence the opening created by a balloon is not always rounded and smooth. The balloons at the tip are the type that expands precisely to certain preset atmospheric pressures.
Hospital stay of would typically be for about 2 to 3 days.