CRT for Heart Failure in Los Angeles

Understanding cardiac resynchronization therapy

What goes wrong when the heart beats out of sync

Your heart has two lower pumping chambers, the left and right ventricles. Normally an electrical signal reaches both at almost the same moment, so they squeeze together.

In some people with heart failure, the signal is delayed on its way to the left ventricle. This often shows up on an ECG as a pattern called left bundle branch block. One part of the heart squeezes early and another part squeezes late, so less blood moves forward with each beat. Doctors call this dyssynchrony.

What a CRT device does

Cardiac resynchronization therapy, sometimes called biventricular pacing, uses a small device placed under the skin below the collarbone. It is connected to leads that sit in the right side of the heart and on the outside wall of the left ventricle.

The device sends small, carefully timed signals so both ventricles contract together. For many people this means the heart pumps more efficiently. Some people notice they can walk farther or breathe more easily, though how much CRT helps varies from person to person.

CRT-P and CRT-D

There are two main types. A CRT-P (a CRT pacemaker) coordinates the heartbeat and also keeps it from dropping too slow. A CRT-D adds the features of an implantable defibrillator, which can treat a dangerous fast rhythm in the lower chambers with pacing or a shock.

Which one suits you depends on your heart function, your rhythm history and your overall health. Your physician will explain the reasoning in plain terms and answer your questions before anything is scheduled.

Who is usually considered for CRT

CRT is generally considered for people with heart failure whose left ventricle pumps weakly and whose ECG shows a delayed, wide heartbeat. It is usually offered after you have been on recommended heart failure medicines for a period of time, because medicines remain the foundation of treatment.

It can also be considered for some people who already need a pacemaker and have a weakened heart, since constant pacing from one side of the heart can make the mismatch worse over time. An echocardiogram, an ECG and a careful review of your symptoms guide the decision.

How the implant is done

The implant is done in the electrophysiology lab with numbing medicine and sedation. Your physician makes a small cut below the collarbone, guides the leads through a vein into position using X-ray imaging, and then tests each one.

Placing the left ventricle lead takes the most care, because it has to reach a vein on the outside of the heart. Once the leads are working well, they are attached to the device, which is tucked under the skin, and the cut is closed. Many people stay in the hospital overnight.

Recovery, follow-up and your care team

For a few weeks you will be asked to limit lifting and reaching with the arm on the device side so the leads can settle. You will get clear instructions about wound care, showering and driving.

Your heart failure medicines usually continue alongside CRT, and your physician may adjust them over time. Talk to your physician before changing any medicine. Most CRT devices send information through remote monitoring, so your care team can see how often the device is pacing and spot changes early.

CRT is part of a team approach. Your electrophysiologist handles the device, while your general or heart failure cardiologist continues to guide medicines, fluid balance and heart imaging. We send clear, detailed notes back to the doctors who referred you, so everyone works from the same plan.

Device reports can also help that team. Changes in how often the device paces, in your heart rhythm or in your activity level can be early clues that your heart failure needs attention.

Risks

CRT implantation is a well-established procedure, but it has risks. These include bruising or bleeding at the device site, infection, a lead moving out of place, and, rarely, injury to the heart, lung or a blood vessel. Some people need a later adjustment to get the timing right. Your physician will go through your own risks and benefits with you before you decide.