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A look inside your heart

Thanks to the inventive use of a long, flexible tube called a catheter, diagnosing heart disease has very nearly become an exact science. Today, in fact, cardiac catheterization is a highly sophisticated, effective and safe procedure that helps doctors pinpoint the location of a blocked artery. It tells them how extensive a blockage is and how narrow the heart valves have become. Doctors can also find out how well the heart is able to pump blood to the rest of the body.

If you’re facing this common, nonsurgical procedure, you probably have a few things on your mind: What goes on exactly during the test? Will I be awake? Does it hurt? How long will it take? How will I feel when it’s over?

Unless your catheterization is being performed on an emergency basis, you’ll likely spend the night before the procedure at home, where you’ll be asked not to eat or drink anything after midnight. In the morning, technicians will shave the areas where the catheter will be inserted (usually at the right elbow or either side of the groin). Because doctors need your cooperation—you may be asked to hold your breath or reposition your arms during the catheterization—you’ll be awake, albeit sedated, throughout the procedure, which takes place on a special X-ray table that moves back and forth.

Your cardiologist will use a local anesthetic to numb the spot where the incision will be made. He or she will then thread a catheter (usually about the diameter of thin spaghetti) through the blood vessel and into the heart.

A television screen shows X-ray images of the catheter as it is threaded through the artery and into the heart’s chambers. The images help the cardiologist guide the catheter into position. With the catheter properly placed, your cardiologist can then carry out necessary tests, such as measuring blood pressure.

If you’re undergoing coronary angiography, a variation of the catheterization technique, your doctor will inject a contrast dye through the catheter into the blood vessels and heart chambers. Coronary angiography produces sharp X-ray images that point doctors to the exact site, shape and extent of blockages—information that can’t be found by any other method.

A cardiac catheterization takes about an hour and can be performed on an outpatient basis. You shouldn’t feel any pain, and discomfort will be minimal. A feeling of pressure is common when the catheter is being threaded through the artery or vein. Sometimes a burning sensation occurs when the contrast dye is injected, but this is a temporary feeling and disappears quickly, as do other, less common reactions such as nausea and vomiting.

After the procedure, you’ll be moved to a recovery room, where pressure will be applied to the incision site, allowing it to seal naturally. A bandage and a small sandbag will maintain pressure until any bleeding has stopped and the staff is sure there are no other complications.

Finally, six to eight hours after undergoing the procedure, you’ll be on your feet again.