Cardiac Resynchronization Therapy

What is cardiac resynchronization therapy?

Cardiac resynchronization therapy (CRT) is a type of treatment that your doctor may recommend if your heart is not pumping as well, or as rhythmically, as it should. When your heart doesn’t pump strongly enough, fluid can build up in your lungs and your legs. This is called heart failure. This condition can happen when your 2 ventricles, or bottom chambers of your heart, don’t beat at the same time. With CRT, a pacemaker-like device is used to get your ventricles to beat together as they should. This treatment may help your heart pump more efficiently, improve your heart failure symptoms, and lower your risk for serious heart problems.

Your doctor may find out that you also need an implantable cardioverter defibrillator (ICD). This device helps fix serious heart rhythm problems. If you need this device, it may be combined with the CRT.

CRT therapy requires placing a device under your skin with minor surgery. Wires from the device are connected to the ventricles on both sides of your heart. The CRT device sends electrical signals to the ventricles to make them pump together the way they should. This type of electrical stimulation is called biventricular pacing.

CRT therapy works in about 70% of heart failure cases. Not everyone with heart failure benefits from CRT. For instance, if you have advanced heart failure, you are not as likely to respond to CRT. Overall, CRT may improve your survival, heart function, and quality of life if you have mild to moderate heart failure. It also improves your ability to exercise.

Why might I need cardiac resynchronization therapy?

Your doctor may suggest CRT for the following reasons:

  • You have moderate to severe heart failure symptoms.
  • The pumping chambers of your heart, called your ventricles, are not working together.
  • Tests show that your heart is weak and enlarged.
  • Medications and lifestyle changes are not working well enough to control your heart failure.

What are the risks of cardiac resynchronization therapy?

CRT is not considered a major or dangerous type of procedure. But like all surgery, it carries some risks:

  • Anesthesia reactions
  • Swelling or bruising in your upper chest area where the CRT device is placed
  • Bleeding
  • Infection
  • Heart rhythm problems
  • Movement of the device or the device wires, which may require a second procedure
  • Mechanical problems with the CRT device

There may be other risks, depending on your specific medical condition. Be sure to discuss any concerns with your doctor before the procedure.

How do I get ready for the insertion of a CRT device?

You should discuss all the risks and benefits of the procedure with your doctor. He or she will probably instruct you to not eat or drink anything after the midnight before surgery. If you usually take medicines in the morning, ask your doctor if you can take them with a sip of water.

Your healthcare team may ask you to stop taking any medicines that thin your blood several days before the procedure. If you take medicines for diabetes, ask your doctor to help you adjust your dose around your surgery. Let your doctor know about:

  • Prescription medicines that you take
  • Over-the-counter medicines or supplements you take, especially aspirin
  • Allergies
  • Recent symptoms of colds or infections
  • History of problems with anesthesia

What happens during insertion of a CRT device?

Your doctor may Insert your CRT device on an outpatient basis, or as part of your stay in a hospital. Procedures may vary, depending on your condition and your doctor's practices. Talk with your doctor about what will happen during your procedure.

The actual procedure may take from 3 to 5 hours. You’ll probably be awake but relaxed and sleepy during the procedure. This is what you can expect:

  • In the procedure room you will lie down on an X-ray table.
  • An intravenous (IV) line will be put into your hand or arm. This is a plastic tube that is inserted through your skin into a vein. Your doctor injects medicines to make you relax, along with pain medicine, into this tube.
  • Your heart, blood pressure, and oxygen level will be monitored.
  • A local anesthetic, or numbing medicine, will be injected into an area on your chest, just below your collarbone.
  • Your doctor will make an incision about 2 inches long through your skin, and find the large vein that returns blood to your heart.
  • Your doctor will then put CRT wires (leads) into your vein and feed them into your heart. Special X-rays will be taken to make sure the leads are in the right place on both sides of your heart.
  • The leads are then tested with an electric pulse. It may feel as if your heart is racing.
  • If the leads are in the right location and working properly, they will be attached to the CRT pacemaker. The pacemaker is inserted through the incision and under your skin.
  • Your doctor will then close the incision with sutures or staples and apply a dressing.

What happens after the CRT device is inserted?

You will be moved to the recovery area, where you'll stay until the relaxing medicine has worn off. A healthcare provider will give you pain medicines, as needed. You may need to stay in the hospital for a day or two while your doctor checks and adjusts the settings on your CRT device.

After you leave the hospital, it will be important to follow all of your doctor's advice and keep all follow-up appointments.

Here’s what you can expect once you’re home:

  • You should be able to follow your normal diet.
  • Activities such as lifting, straining, and stretching may be limited for the first 6 weeks. Ask your healthcare provider when you can return to specific activities.
  • Until your healthcare provider tells you it is OK to remove the dressing and take a shower, keep the dressing clean and dry.
  • Check your incision area for any signs of infection. Let your healthcare provider know if you have any fever, redness, soreness, discharge, bleeding, or swelling.

Here are likely long-term instructions for living with your CRT device:

  • Make sure to have your doctor check the functioning of your device regularly. This should be done at least once every 6 months.
  • Carry a CRT pacemaker identification card and let all your caregivers know about your device.
  • Your pacemaker battery will last for about 4 to 8 years. Your doctor will be able to tell about 6 months before the battery runs down. Replacing the CRT pacemaker is a minor procedure.
  • It’s a good idea to keep all electrical devices about 6 inches away from your CRT pacemaker. They can interfere with its function.
  • You may need to avoid close contact with devices that have strong magnetic fields. These include cellular phones, mp3 players, electrical generators, and appliances like microwaves. Talk with your healthcare provider if you have any questions about what to avoid.
  • Most X-rays and metal detectors are safe, but you should avoid metal wands used for airport screenings and MRI imaging tests.

Next steps

Before you agree to the test or the procedure make sure you know:

  • The name of the test or procedure
  • The reason you are having the test or procedure
  • The risks and benefits of the test or procedure
  • When and where you are to have the test or procedure and who will do it
  • When and how will you get the results
  • How much will you have to pay for the test or procedure