Heart failure

Congestive Heart Failure and Cardiac Resynchronization Therapy (CRT)

Heart failure occurs when your heart is no longer able to pump enough blood to meet your body’s needs. Sometimes it is also called congestive heart failure.

For many people with heart failure, cardiac resynchronization therapy (CRT) can be a life-saving treatment. It synchronizes the beats of the two lower chambers of your heart (ventricles) so that the heart can pump blood more efficiently.

CRT uses an implantable device placed in the chest. The device has wires (called leads) that connect to the heart. These leads carry a small electrical signal to stimulate the ventricles.

There are certain risks associated with the CRT procedure. But technological advancements continue to improve the CRT and its efficiency.

Heart failure can result from conditions that weaken the heart muscle. These conditions include:

Heart failure is often classified based on the heart’s ability to pump blood throughout the body, as shown below:

When the ventricles beat at different times, the heart cannot function efficiently.

As a result, fluid can build up in the lungs and legs. These are the hallmark symptoms of congestive heart failure. If left untreated, they can lead to a dangerous reduction in blood flow to organs and the rest of the body.

CRT uses a pacemaker to help the heart’s upper chambers (atria) beat at a coordinated rate with the lower chambers (ventricles). With CRT, the heart constantly receives electrical impulses that promote a more coordinated beating and relaxation of the heart. This helps support better blood circulation.

The use of the CRT has grown steadily since it was first approved in 2001. However, a report 2016 suggests that the vast majority of people who undergo CRT are male and white, and that significant racial and socioeconomic barriers to this treatment still exist.

CRT is usually only an option after medications or other treatments have failed to stimulate the heart’s pumping function.

Your doctor will likely explain the procedure to you and review the benefits and risks.

Once you and your doctor decide to proceed with CRT, they will give you more instructions on what to do before the procedure. This will likely include details on:

  • when to stop eating or drinking fluids before the procedure
  • when to stop taking medications or supplements that can thin your blood
  • when it may be safe to take other prescription medications for your heart or other conditions

Depending on the severity of your condition, your doctor may decide to perform CRT as part of a hospital stay or on an outpatient basis.

A CRT stimulator battery can last up to 8 years. Your doctor will be able to tell months before the battery is likely to run out so you can schedule a replacement procedure.

You will also need to carry a CRT ID card with you to inform all other doctors of your status. It’s also useful if you have to go through a metal detector at the airport or other places.

What are the prospects?

Many factors contribute to the outlook after someone undergoes CRT. Age and general health, including comorbidities (other health conditions), are two key considerations.

A study 2021 of people who received their CRT device between 2011 and 2013 suggests that the average 5-year survival is around 58%.

However, a study 2018 using patient data from 2009 to 2017 suggests that relative survival continues to improve year over year and that survival rates were significantly higher from 2015 to 2017 than they were from 2009 to 2011.

A report 2019 suggests that ongoing developments in device probes and cardiac imaging allow physicians to be even more precise with this procedure, which may lead to even greater improvements in cardiac function.

Like any medical procedure, the implantation of a CRT carries certain risks. But complications such as bleeding or infection are unusual. In rare cases, the therapy can trigger an arrhythmia.

Mechanical issues, such as a cable coming loose or the device not sending out pulses correctly or consistently, can sometimes occur. Therefore, you may need to perform a second procedure to replace the device or probe. In general, however, CRT is considered a safe, low-risk treatment for suitable individuals.

The device should also only be implanted if your doctor thinks it will bring significant improvement. Some people with heart failure are too weak or ill to undergo the procedure and benefit from resynchronization therapy.

If you have HFpEF or no arrhythmia is detected with your type of heart failure, CRT should not be considered.

Although CRT can help many people with heart failure return to some of their usual activities and improve their quality of life, it is not a cure. Although you can often manage heart failure, it cannot be cured.

It should be noted that CRT is usually only one component of treatment for heart failure. If you have heart failure, you may also be prescribed antihypertensive drugs to lower blood pressure, including beta-blockers, which slow the heart rate and relieve the heart muscle.

You may be prescribed other medications, including digoxin (Lanoxin), which strengthens heart contractions. And, if you have high cholesterol, you may need to take a statin to lower your LDL (“bad”) cholesterol levels.

Depending on the cause, heart failure can be treated with other procedures. For example, if you have valve disease, surgery or catheter-based procedures to replace or repair a valve may improve your symptoms.

CRT can be a helpful option for many people with heart failure. In particular, it is an appropriate treatment for people with HFrEF who have an arrhythmia that prevents their heart from beating at a regular rate.

CRT uses a pacemaker to help the upper chambers of the heart beat in a coordinated rhythm with the lower chambers. This, in turn, helps blood flow more efficiently throughout the body.

CRT does not cure heart failure, but it is a therapy that prolongs the lives of many people with heart failure and enables a quality of life that was not possible just decades ago.

If you undergo CRT, lifelong monitoring and regular check-ups with your cardiologist will be required.