Overview of Cardiac Catheterization
Cardiac catheterization is a common, non-surgical procedure performed in a catheterization laboratory (cath lab). Cardiac catheterization allows your healthcare providers to do many different tests and measurements to diagnose and treat problems with your heart and coronary arteries (the arteries that supply blood to your heart muscle).
A narrow tube is inserted into the femoral artery (groin), threaded through the arterial system, and into the arteries that surround and supply blood to the heart. A contrast dye is injected, and X-ray pictures are taken to diagnose the disease. This imaging portion of the test is also referred to as coronary angiography.
Diagnostic Techniques Used During Cardiac Catheterization
The following are descriptions of the most common diagnostic procedures performed in the cath lab:
- Left ventriculogram: A left ventriculogram is like an angiogram, but the x-ray contrast is injected into the left ventricle, instead of into the coronary arteries. This shows blood flow through and out of the left ventricle. A ventriculogram can measure your ejection fraction (EF), which is the amount, or percentage, of blood the heart pumps out with each beat.
- Right heart cath: In a right heart cath, a catheter is threaded into the right side of the heart and into part of your lungs. Your providers can then measure pressures in your heart chambers and check your heart valves. They can also measure the amount of oxygen in the blood in different areas of your heart. This provides important information about overall heart function.
- Cardiac biopsy: In a cardiac biopsy, a catheter with a small grasping device is threaded into your heart muscle (myocardium) to extract a small piece of tissue.
- Coronary pressure wire: This test can help diagnose whether a narrowed section of a coronary artery is likely to cause problems in the future. The catheter is attached to a sensor that measures the blood pressure in the artery before and after the narrowed area.
- Heart valve assessments: During a catheterization, healthcare providers can also measure blood pressures in — and blood flow through — the heart chambers to tell if the heart valves are working properly.
- Intracardiac echo (ICE): In this test, the catheter carries an ultrasound sensor to give an image of the heart’s internal structure. ICE is often used for guidance as devices or balloons are placed in the heart.
- Intravascular ultrasound (IVUS): This test uses high-frequency sound waves to create a motion picture of the interior of your coronary arteries. The catheter carries a device called a transducer, which sends out sound waves that bounce off the artery structures. These wave echoes are converted into images on a monitor.
- Electrophysiology (EP) studies: A catheterization procedure in which small electrical impulses are delivered to the heart to help evaluate heart rhythm abnormalities.
Interventional Techniques Used During Cardiac Catheterization
If the problem is diagnosed as a blockage of one or more arteries in the heart, then several interventional techniques can be used to open these coronary arteries blocked by plaque. Plaque is a substance that builds up on the artery wall like hard water deposits in a pipe.
- Angioplasty: A small balloon inflates to compact plaque against the arterial wall. This procedure takes approximately one hour.
- Stent placement: A small, metal, mesh device acts as a permanent scaffold to prevent arterial collapse. This procedure will take about 60 minutes.
- Rotablator: This device shaves off layers of plaque from the arterial wall.
- Excimer laser: A laser removes arterial plaque by burning it off.
- Brachytherapy: Brachytherapy uses beta radiation to keep blocked heart arteries open. It is usually combined with angioplasty and stent placement.
- DES (drug eluting stents): Stents are coated with a drug to prevent restenosis.
- AngioJet: This device extracts clots from the artery.
Learn what happens (and what you need to do) before, during, and after cardiac catheterization: