What is Cardiac Catheterization
Different access sites that may be used during cardiac catheterization proceduresCardiac Catheterization (Cath) is a specialized study of the heart during which a catheter, or thin hollow flexible tube with a soft tip, is inserted into the artery of the groin or arm. Under x-ray fluoroscopyreal-time moving images are used to guide the tip of the catheter to the heart. Pressures are measured and an x-ray angiogram (angio) video of the heart and blood vessels are recorded while injecting an iodinated colorless "dye" or contrast materialthrough the catheter. 
 Coronary angios are obtained by injecting the contrast material into the opening or mouth of a coronary artery. The liquid within the artery blocks x-ray beams and enables it to be temporarily visualized. This is similar to a shadow being cast on a screen when an opaque object is placed in front of a bright light. The procedure is used to identify the presence and severity of coronary artery stenosis or blockage.
 In other words, coronary arteries are not visible on x-ray film. However, they can be made temporarily visible by filling the coronary artery with a contrast solution that blocks x-ray.
The coronary arteries are vital because they supply oxygen and nutrients to the heart muscle. Without blood flow, the muscle would sustain permanent damage in the form of a heart attack or myocardial (pronounced my-o-card-yull) infarction (pronounced in-fark-shun).

Cardiac Catheterization (Cath) is also known as Heart Cath, angiogram (Angio, pronounced an-gee-o-gram) or arteriogram (pronounced art-e-rio-gram). The latter two terms describe the use of contrast material to take x-ray pictures of the heart and blood vessels.

   If catheters are introduced through the femoral (pronounced fem-rull) or groin artery, the procedure is known as "left heart" catheterization, because the catheter goes from the femoral artery to the aorta, coronary arteries, and the left ventricle (LV). This accounts for the majority of procedures. Left heart cath can also be performed by using the artery near the elbow (brachial) or wrist (radial).

If a catheter is also placed in the right femoral vein to measure pressures within the right side of the heart, the procedure is called "right heart" catheterization. This is used in patients with congenital heart disease, diseases of the heart valve, or certain conditions involving the pericardium (pronounced peri-card-e-yum) or sac of the heart. This may also be used in certain diseases of the heart muscle, heart failure, shock, or when measurements of heart output or lung pressures are needed. Right and left heart catheterization is a combination of the two.

This page was reviewed and updated on August 28, 2011


 Preparing for Cardiac Catheterization
Cardiac Catheterization (cath) may be performed during a hospitalization (inpatient) or as an outpatient procedure, when the patient is admitted and discharged on the same day of the procedure.

If an outpatient procedure is planned, the following checklist needs to be followed:

  • Pack a small overnight bag in case you need to spend the night in the hospital. Leave all valuables at home. Pack your contact lenses (with solution) and eye glasses if you wish to view the pictures during the procedure.
  • If the procedure is scheduled prior to noon, do not eat or drink after midnight. Medications prescribed by your doctor may be taken with sips of water. If the procedure is scheduled for the afternoon, you may be allowed to have an early liquid breakfast (juice, tea, broth, water, etc.) prior to 7 AM if you are instructed to do so.
  • Make certain that you have directions to the Cath Lab and the time that you are to report there. Call your doctor's office or the facility if you have any questions. Also, make sure that you receive instructions about eating, drinking, and the use of prescribed medications.
  • Diabetic patients, particularly those on insulin, need clarification about the insulin dose and whether it will be used before or after the procedure.
  • If you are given lab results and an electrocardiogram (EKG) by your doctor, please be sure to give them to the nurse when you arrive. Also, bring all your regular medicines (or at least a list) with you.
  • The preparations are similar if you are already hospitalized on the day of the procedure.
  • Make arrangements to have a family member or friend drive you home. There is a waiting area provided for their use.
 

 Initial steps after arriving at the facility
Blood pressure and pulse check
  • You will register or check in at the admission desk
  • If you have not had recent blood work or an EKG, they will be obtained by the nurse.
  • You will receive instructions about the procedure and what is expected for the day. Your doctor or office staff may already have discussed the procedure, risks and indications with you. You will be asked to sign a consent form. Feel free to ask any questions.
  • Your blood pressure, pulse rate, temperature and oxygen level will be checked
  • You will be questioned about your history, medications, and allergies. Nurse obtaining information(If you have an allergy to iodine andshellfish, or have had prior problems during an x-ray procedure or cardiac cath, please be sure to notify the nurse.)
  • You will then change into a hospital gown.
  • Make sure that you empty your bladder before being taken to the cath lab. intravenous line placed in the arm
  • The pulse area on your arm or leg may be marked with a felt-tip pen.
  • An Intravenous (IV) will be started in your arm with the use of a small needle or plastic tube. This will allow the administration of fluids and medications.
  • You may be given medicines (by mouth or IV) to help you relax.
  • When preparations are complete and the cath lab is ready, you will be transferred there.

  •  Shaving, Transfer to the Cath Table and Scrubbing
    The groin is shaved in preparation for cardiac catheterizationCatheters are most commonly introduced through a tiny needle hole in the right groin. However, both groin areas are usually shaved in case the other groin has to be used in cases of technical difficulty. Cardiac catheterization (cath) may also be performed through a needle hole above the elbow (brachial artery) or wrist (radial artery). Shaving is usually carried out before the patient is brought to the laboratory (lab). However, it may be carried out in the lab in case of an emergency procedure.
    Patient being transferred to the cardiac cath tableThe patient is transferred from the stretcher or rolling bed and on to the cath table. The technologists (Techs) and nurse reassure the patient and explain what will happen next. They also confirm the identity of the patient and the clinical history of the patient, including a review of allergies.
    Groin area being scrubbed with a sterile solutionBoth groin areas are scrubbed with a sterile solution to further reduce the risk of infection. The fluid may contain an iodine solution and the cath team (techs, nurse and cardiologist) usually wear latex gloves. Thus, it is extremely important to notify them if there is known allergy to either material.
    The patient being draped with sterile materialThe areas around both groins are covered with sterile drapes and material, leaving a small uncovered area around both groins. Similar preparations are used around the elbow or wrist if the brachial or radial artery approach is used by the cardiologist.
    Sedation, numbing & introducing the needle, wire and sheath
    IV equipment and tubingIntravenous medications are used to relax the patient. This is usually injected through the existing intravenous lines. Intravenous fluid is also given during the cardiac cath procedure. The patient is able to ask questions and follow the instructions of the cardiologists, nurses and Techs. This can include having to take a deep breath or let the cath team know if there is any discomfort that is being experienced. The goal is to keep the patient extremely comfortable and relaxed without being put to sleep. This process is known as "conscious sedation".
    The groin area is being numbed with use of local anesthesiaThe groin area is then "numbed" with the use of local anesthesia. This is performed by injecting lidocaine into the skin and adjoining area. The process is similar to a dentist numbing the mouth and gum prior to a dental procedure. The patient may feel a temporary stinging sensation at this time.
    Needle being introduced into the arteryThe artery pulse is felt or palpated by the cardiologist's fingertips and a needle is directed toward the arterial pulsation. When blood spurts out of the needle, the cardiologist knows that entrance to the artery has been achieved. Since the area was previously "numbed" with local anesthesia, there is usually very little discomfort experienced by the patient.
    Wire introduced through the needleA thin flexible wire is then introduced through the channel of the needle. The wire is known as a guide-wire because it helps guide catheters, just like a rail guides the path of a train. The purple plastic "tip deflector" helps straighten the curved and floppy tip of the guide wire until it is passed into the needle. The needle and the tip deflector are then removed, leaving the wire through the needle hole and in the artery.
    Advancing wire and introduction of sheath
    Cardiac catheterization equipmentFluoroscopy is a technique that uses x-ray to visualize moving structures in real time. X-ray is beamed up from an x-ray tube below the table, passes through the patient and is captured by a device called an image intensifier that is positioned above the patient. The image is then captured by a TV camera and displayed on a video monitor. The x-ray tube and Image Intensifier are connected to each other by a "C Arm" that keeps them aligned as the C Arm is made to rotate to either side and/or up and down. The table can also be moved.
    Wire is guided using fluoroscopyThe wire is advanced and the tip is gently guided up the aorta using fluoroscopy and watching the video monitor.
    The sheath is advanced over the guidewireA sheath is a tubular and flexible thin walled plastic tube that is usually about 2 or 2 1/2 millimeters in diameter (thickness). A tapering tip introducer insert stiffens the soft sheath and prevents it from being damaged as the sheath/introducer is advanced over the guide-wire as a unit.
    Sheath placed in right groinThe introducer is removed after insertion of the sheath. The outer end of the sheath contains a plastic hub with a one-way rubber valve that allows catheters to be introduced through the sheath but prevents blood from escaping out. The outside end of the sheath also contains a side plastic tube that allows the sheath to be flushed with liquid, measure the pressure of the artery and withdraw blood samples. 
    The sheath serves as a passage or channel through which catheters are inserted.
     
    Advertisement