When people hear the word catheterization, many think of the urinary tract. Cardiac catheterization is something different: a procedure in which a thin, flexible tube called a catheter is threaded through a blood vessel to the heart. From there, a cardiologist can measure pressures inside the heart, check how well it pumps, and inject contrast dye to take X-ray pictures of the coronary arteries. When those pictures show a significant blockage, the same procedure can often be used to open it.
Cardiac catheterization is invasive, but it answers questions that noninvasive tests cannot fully settle. The National Heart, Lung, and Blood Institute describes it as a procedure used to diagnose and treat some heart conditions, and notes that problems afterward are rare but can include bleeding and blood clots.
NYMD Center does not perform cardiac catheterization. When you need one, we refer you to an interventional cardiologist and coordinate your care before and after: preparing your records, labs and ECG, planning around your medications, and following up with you once it is done. This page explains what the procedure involves so that you know what to expect and what to ask.
What cardiac catheterization is and who needs it
The most common reason for catheterization is to look for narrowed or blocked coronary arteries, the vessels that feed the heart muscle. This part of the procedure is called coronary angiography. Contrast dye is injected through the catheter, and X-ray images show exactly where and how severely an artery is narrowed. Mayo Clinic lists other diagnostic uses, including checking pressure and oxygen levels in different parts of the heart and assessing how well the heart pumps. It can also be used to evaluate heart valves or take a small tissue sample.
A cardiologist may recommend catheterization when you have chest pain or other symptoms that suggest coronary artery disease, particularly if they are getting worse or not responding to medication; when a stress test or imaging study shows a high-risk result; after a heart attack; or when valve disease or heart failure needs precise measurements before treatment. In an emergency heart attack, catheterization is often done right away in the hospital to reopen the blocked artery.
When a significant blockage is found, the cardiologist may treat it during the same procedure. This is called percutaneous coronary intervention (PCI). A small balloon is inflated inside the narrowed segment to widen it, and a stent is usually placed to keep it open. The NHLBI describes a coronary stent as a small mesh tube, most often a drug-eluting stent coated with medication that helps keep the artery from narrowing again. Not every blockage needs a stent, and some patients with disease in several arteries are better served by bypass surgery or by medication alone. Those decisions are made by the cardiology team with you.
How we prepare you at NYMD Center
Most people arrive at catheterization after an evaluation that begins in our office. We take a careful history, examine you, and record an ECG in the office. When the heart is in question, we arrange an echocardiogram or a stress test and review the results with you. If those findings point toward a significant blockage, we refer you to an interventional cardiologist.
Once catheterization is planned, our role is to get you ready safely, much as we do for pre-op clearance. That includes:
- Pre-procedure blood work, including kidney function, a blood count and, when relevant, blood sugar, since the contrast dye is cleared by the kidneys.
- An up-to-date ECG and a medication list to send to the cardiology team.
- A plan for blood thinners, which may need to be held or continued depending on the reason you take them and the cardiologist's instructions.
- A plan for diabetes medications. Mayo Clinic notes that contrast dye may increase the risk of side effects from some diabetes medicines, including metformin, and insulin doses often need adjusting around fasting.
- Flagging any prior reaction to contrast dye or iodine, so it can be addressed before the procedure.
How the procedure works
Catheterization is done in a hospital catheterization lab. You receive medication through an IV to help you relax, and the skin over the access site is numbed. According to Mayo Clinic, the catheter is usually placed in a blood vessel in the wrist or the groin. The wrist (radial) approach allows you to sit up and move sooner, while the groin (femoral) approach may be preferred for some procedures. Using X-ray guidance, the cardiologist advances the catheter to the heart, takes measurements, and injects dye to image the arteries. You may feel a brief warm flush when the dye goes in. The catheter itself is usually not felt inside the blood vessels.
Risks
Mayo Clinic describes the risk of major complications as generally low. Possible problems include bruising or bleeding at the access site, blood clots, damage to the artery, infection, irregular heart rhythms, an allergic reaction to the dye, kidney damage from the dye, and, rarely, heart attack or stroke. Kidney risk is higher in people who already have reduced kidney function or diabetes, which is one reason we check your labs beforehand and follow up afterward.
Recovery
You usually spend a few hours in a recovery area. If the catheter went in through the groin, you may need to lie flat for several hours to prevent bleeding. Some people go home the same day, while others stay overnight, especially after a stent. The NHLBI advises following instructions on caring for the access site and asking when you can resume lifting and physical activity. After a stent, you will usually take aspirin and another antiplatelet medicine; the NHLBI notes this is often continued for a year or longer to prevent clots in the stent, so it must not be stopped without talking to your cardiologist.
What to expect at your visit
Before the procedure, plan on a visit for history, exam, ECG and blood work, and bring a complete list of your medications, including over-the-counter products and supplements. We send your records to the cardiology team and go over the fasting and medication instructions with you. After the procedure, we see you back to check the access site, review the catheterization report with you, confirm your new medications, recheck kidney function when dye was used, and continue managing blood pressure, cholesterol and diabetes. Our cardiology page describes how we coordinate heart care across the group.
When to seek care urgently
Call 911 for chest pain or pressure, shortness of breath, or stroke symptoms such as facial droop, one-sided weakness or trouble speaking. After catheterization, the NHLBI advises contacting your doctor right away for bleeding from the access site that does not stop with firm pressure, swelling at the site, fever, or chest pain. A cold, pale or numb hand or leg on the side of the access site also needs prompt attention.
Questions patients ask
Does NYMD Center perform cardiac catheterization?
No. Cardiac catheterization is performed in a hospital catheterization lab by an interventional cardiologist. Our physicians evaluate your symptoms, do an ECG in the office, arrange tests such as an echocardiogram or stress test, and refer you when catheterization is needed. We then coordinate your pre-procedure labs and medications and follow up with you afterward.
Is cardiac catheterization done through the wrist or the groin?
Either can be used. The catheter is usually placed in a blood vessel in the wrist or the groin. The wrist approach often lets you sit up and walk sooner, while the groin approach may be preferred for certain procedures. The interventional cardiologist chooses the site based on your anatomy and what the procedure needs to accomplish.
What is the difference between an angiogram and a stent?
Coronary angiography is the diagnostic part: contrast dye and X-rays show whether and where the heart arteries are narrowed. If a significant blockage is found, the cardiologist may open it during the same procedure with a balloon and usually a stent, a small mesh tube that holds the artery open. This treatment is called percutaneous coronary intervention.
Do I need to stop my blood thinner or diabetes medication?
Possibly, but only on specific instructions. Some blood thinners are held before catheterization and others are continued, depending on why you take them. Metformin and insulin often need adjusting because of fasting and the contrast dye. We review every medication with you and coordinate the plan with the cardiology team, so do not stop anything on your own.
How long is recovery after cardiac catheterization?
Most people spend a few hours in recovery, and some go home the same day, while others stay overnight, especially after a stent. After a groin approach you may need to lie flat for several hours. Ask the cardiology team when you can lift, exercise and bathe, and keep follow-up visits so we can check the site, labs and medications.