Cardiac catheterization involves passing a catheter (a thin flexible tube) into the right or left side of the heart. In general, this procedure is performed to obtain diagnostic information about the heart or its blood vessels or to provide treatment in certain types of heart conditions. It can be used to determine pressure and blood flow in the heart's chambers, collect blood samples from the heart, and examine the arteries of the heart with an x-ray technique called fluoroscopy. Fluoroscopy provides immediate ("real-time") visualization of the x-ray images on a screen and provides a permanent record of the procedure
Food and fluid are restricted 6 to 8 hours before the test. The procedure takes place in the hospital and the patient will be asked to wear a hospital gown. Sometimes, admission the night before the test is required. Otherwise, the patient will be admitted as an outpatient. The health care provider should explain the procedure and its risks. A witnessed, signed consent for the procedure is required. The patient should tell the doctor if he is allergic to seafood, if there is a bad reaction to contrast material in the past, if taking Viagra, or if the patient might be pregnant. The study is carried out in a laboratory by a trained cardiologist or radiologist and technicians or nurses. The patient is awake and able to follow instructions. A mild sedative is usually given 30 minutes before the procedure. The procedure may last from 1 to several hours. The patient may feel some discomfort at the site where the IV is placed. Local anesthesia will be used to numb the site, so the only sensation should be one of pressure at the site. After the test, the catheter is removed and the patient might feel a firm pressure at the insertion site, used to prevent bleeding.
Cardiac catheterization is usually performed to evaluate heart valves, heart function and blood supply, or heart abnormalities in newborns. It may also be used to determine the need for heart surgery. Therapeutic catheterization may be used to repair certain types of heart defects, open a stenotic heart valve, and open blocked arteries or grafts in the heart.
Cardiac catheterization carries a slightly increased risk when compared with other heart tests. However, the test is very safe when performed by an experienced team. Generally, the risk of serious complications ranges from 1 in 1,000 to 1 in 500. The risks include the following: cardiac arrhythmias, cardiac tamponade, trauma to the artery caused by hematoma, low blood pressure, reaction to contrast medium, hemorrhage, stroke, heart attack.