What is Cardiac Catheterization?
This procedure (sometimes called a coronary angiogram, heart catheterization or, simply, a “cath”) is basically an x-ray of the heart while dye fills the coronary arteries. This allows the cardiologist to visualize the coronary arteries to evaluate possible blockage.
What are the indications for the procedure?
Most often we do this test when we suspect blockages in the arteries that feed the heart muscle (coronary artery disease). Patients will frequently have already undergone a screening stress test that turned out abnormal. We then follow this with the more definitive cardiac catheterization. Sometimes patients will describe chest symptoms that are so convincing of coronary artery disease that we bypass the stress test and go straight to cardiac catheterization. Also, when patients come through the emergency room with a heart attack we will proceed directly to cardiac catheterization.
How is it done?
When we’re ready to start you’ll be brought into the cardiac catheterization lab (much like an operating room with x-ray cameras) and you’ll lie on a table while our technicians prepare the area on your body where we’ll be working. In most patients we get access to the arterial system through the femoral artery in the right or left groin. In some cases we use the artery in the wrist or upper arm.
You’ll receive some light sedation through your IV. Our goal is to make you comfortable without putting you all the way out. If, during the procedure, you find yourself anxious just let us know and we can give you more medication. We then numb the skin with anesthetic (this is the only part that should be painful in any way) and place a sheath (much like an IV) into the artery.
Through the sheath we pass catheters of various sizes and shapes that extend up through the aorta and sit in the opening of the coronary arteries. We inject a small amount of iodine-based dye into the artery and film it with an x-ray camera. This allows us to see the arteries in great detail and we can tell you right away what we’ve found and what our recommendations are.
If the study is normal (no significant blockage) we remove the sheath and send you back to the recovery area. We frequently use a device to close the hole we made in the artery so that you can get up and around sooner. Sometimes we have to seal the hole by holding pressure for 15-20 minutes and have you lie on your back for several hours. Once you’ve recovered for a sufficient period you’ll be dismissed with instructions on how to take care of the access site and what activity you can pursue.
If we find blockage we can frequently fix it using a balloon catheter and stent. In this case we keep you in the hospital overnight for observation. Occasionally we find enough blockage in several vessels, or blockage in a high-risk region, that we need to recommend coronary artery bypass surgery. We generally dismiss you from the hospital that same day and have you visit one of our cardiovascular surgeons to discuss and arrange the surgery.
How do you prepare for the procedure?Cardiac catheterization is done on both hospitalized and ambulatory patients. As an outpatient having this done electively you will first visit with the cardiologist in the office to go over the procedure and discuss the risks and alternatives. Since you will be asked to sign document of consent be sure to ask any question and raise any concern you may have. You will need to have basic blood work done and this can be drawn in the office.
Unless instructed otherwise you should be fasting on the morning of the procedure. In general we want you to take your usual morning medications with the exception of any we’ve told you not to take (please talk to our nurses or schedulers if you have any questions about this).
We do this procedure in the hospital at Mercy, Midlands, Bergan, Immanuel and Lakeside and you’ll receive specific instructions on where to show up and what time to be there.
What are the risks of the procedure?
Because this is an invasive test there are certain grave risks that you need to be aware of. Fortunately we encounter these extremely rarely. The risk of death, heart attack or stroke is less than 1 in 1000. Bruising at the access site occurs in many people but very few of these will have enough bleeding into the groin that we have to surgically address this. The IV contrast can rarely cause an allergic-type reaction in people with a history of iodine allergy and can be harmful to patients with poor kidney function.