Cardiology: Invasive

Cardiac catheterization, also known as a ‘cardiac cath,’ is frequently used for diagnosis and treatment of a wide variety of heart conditions. This procedure involves a long thin tube (the catheter) being inserted into an artery in the patient’s arm, groin, or veins of groin or neck, and then guided through the circulatory pathway to the heart.

Cardiac catheterizations may be done to assess coronary arteries for blockages and/or to assess the status of heart valves. Blood pressures in the various chambers of the heart and lungs can be measured to determine the function of the heart. Depending on the findings, a coronary intervention may be undertaken to place a stent into the diseased artery.

Cardiac catheterization, also known as a ‘cardiac cath,’ is frequently used for diagnosis and treatment of a wide variety of heart conditions. This procedure involves a long thin tube (the catheter) being inserted into an artery in the patient’s arm or groin, and then guided through the circulatory pathway to the heart. In a right-heart catheterization, the doctor guides a special catheter (a small, hollow tube) called a pulmonary artery (PA) catheter to the right side of the heart. He or she then passes the tube into the pulmonary artery. This is the main artery that carries blood to the lungs. The doctor observes blood flow through the heart and measures the pressures inside the heart and lungs.


Your doctor may do a right-heart catheterization to see how well or poorly your heart is pumping, and to measure the pressures in your heart and lungs. This test is also known as pulmonary artery catheterization.


As the catheter advances toward your pulmonary artery, your doctor measures pressures along the way, inside the chambers on the right side of your heart. This includes the right atrium and right ventricle. Your doctor can also take indirect measurements of pressures on the left side of your heart. Your cardiac output—the amount of blood your heart pumps per minute—is also determined during a right-heart cath.


Right heart catheterization is used to diagnose or manage:

  • Heart failure. A condition in which your heart muscle has become so weak, it can’t pump blood efficiently. This causes fluid buildup (congestion) in your blood vessels and lungs. Fluid may also buildup in your feet, ankles, and other parts of your body.
  • Shock. This causes reduced flow of blood and oxygen to the tissues of your body. Sudden onset of heart failure, severe bacterial infection of your blood stream (sepsis), or severe blood loss (hemorrhagic) can cause shock.
  • Congenital heart disease. These are birth defects that develop in the heart. An example is ventricular septal defect. This is a hole in the wall between the lower chambers of your heart.
  • Heart valve disease. Malfunction in one or more of your heart valves may interfere with normal blood flow within your heart.
  • Cardiomyopathy. This is an enlargement of your heart due to thickening or weakening of your heart muscle. It can eventually lead to heart failure.
  • Pulmonary hypertension. Increased pressures in the blood vessels in your lungs. This can lead to trouble breathing and right-sided heart failure.

In an angiogram, X-rays are used to determine whether plaque has blocked the blood vessels. During this test, which requires local anesthesia, a doctor makes a small incision in the skin near the groin, inserts a thin tube called a catheter, and guides it into an artery. The doctor moves the catheter to the area to be examined and injects a dye that highlights any narrow, enlarged, or blocked blood vessels.

Coronary stents are small, wire, mesh tubes that help widen a clogged artery and restore adequate blood flow to the heart. A cardiologist will place the stent over a thin, long tube with a balloon tip called a catheter and insert it into an artery in the groin or arm. Once the stent reaches the clogged artery, the doctor will inflate the balloon to expand the stent. When the stent reaches the desired size to widen the clogged artery, the doctor will deflate and remove the balloon. The stent will stay in place permanently to help prop open the artery and decrease its chance of narrowing again. Over time, the inner lining of the artery will grow over the surface of the stent, making it a permanent part of the artery.

Transradial catheterization is an approach to [cardiac catheterization] wherein the catheter is inserted into an artery in the patient’s arm, and then guided through the circulatory pathway to the heart. In clinical trials, this approach has been associated with faster recovery times and lower bleeding rates, particularly in women.

During rotational atherectomy, a revolving instrument is introduced via a catheter and used to break up calcified plaque that is clogging a coronary artery. The device rotates at a speed of up to 150,000 rpm, gently pulverizing the blockage into tiny particles that can pass safely through the bloodstream. Breaking up the plaque restores blood flow to the heart. The technique is used when blockages are particularly difficult to remove.