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Cardiac resynchronization therapy (CRT) device support

How CRT works

Background image of CRT

Cardiac resynchronization therapy (CRT) devices help your heart beat more efficiently and monitor your condition so your doctor can provide the right treatment for you. Find out more about how your device works below.


About heart failure

If you have heart failure, your heart doesn’t pump as well as it should, so your blood doesn’t circulate as well as it should to supply your body with the oxygen and nutrients it needs to thrive.

In a healthy heart, both ventricles (lower part of the heart) pump or beat at exactly the same time in a coordinated way. It’s like making a fist—all of the fingers squeeze in unison. But for many people with heart failure, the ventricles do not pump at the same time. It’s like making a fist just one finger at a time.


What is a CRT device?

A CRT system consists of two components—the pulse generator, or device, and thin, insulated wires called leads. A CRT device delivers tiny amounts of electrical energy to the heart through these leads. This helps restore the normal timing of the heartbeats, causing both ventricles to pump together more efficiently like a fist closing normally again.


How do CRT devices work?

There are two types of CRT devices.

One is a special kind of pacemaker. It’s called a cardiac resynchronization therapy pacemaker (CRT-P) or "biventricular pacemaker." The other is the same device, but it also includes a built-in implantable cardioverter defibrillator (ICD). This type is called a cardiac resynchronization therapy defibrillator (CRT-D).

An implanted CRT-P system

human heart image of implemented CRT-P device

While functioning like a normal pacemaker to treat slow heart rhythms, a CRT-P device also delivers small electrical impulses to the left and right ventricles to help them contract at the same time so your heart pumps more efficiently.

An implanted CRT-D system

human heart image of implemented CRT-D device

A CRT-D is a special device for heart failure patients who are also at high risk for sudden cardiac death. While functioning like a normal pacemaker to treat slow heart rhythms, a CRT-D device also delivers small electrical impulses to the left and right ventricles to help them contract at the same time. This will help your heart pump more efficiently.

A CRT-D device can also treat dangerously fast heart rhythms (arrhythmias) that can lead to sudden cardiac arrest. If the device senses heartbeats that are dangerously fast, it delivers a shock to the heart. This shock (defibrillation) stops the abnormal rhythm. Without this life-saving therapy, the dangerously rapid rhythm could lead to death in just minutes.


Learn more about your device's battery.

Like any battery, the energy in your implanted device will decrease over time. The battery’s life is affected both by how much energy is programmed to deliver the electrical impulse and how often it is required to pace or deliver therapy to your heart. Your doctor will program the device to meet your individual needs. 

Your CRT device will regularly check its own battery and your doctor will check to see how much energy it has left at each follow-up visit. In addition, your doctor can turn on a feature that makes your device beep when replacement time is near. Call your doctor immediately if your device beeps.


Implant risks

While complications don’t happen very often, it’s important to know that there are risks associated with the implantation of any device or lead. You should talk with your health care team about these risks. 

See our patient manuals for detailed safety information. 

Download the CRT-P Patient Handbook 

Download the CRT-D Patient Handbook

We’re here to help

Our patient services team is happy to help answer all your questions about living with your device.

Hours: M-F 8:00 a.m. - 5:00 p.m. Central

Email us

References

1. PHYSICIAN'S TECHNICAL MANUAL RESONATE™ HF CRT-D, RESONATE™ CRT-D, RESONATE™ X4 CRT-D, VIGILANT™ CRT-D, VIGILANT™ X4 CRT-D, MOMENTUM™ CRT-D, MOMENTUM™ X4 CRT-D. Part Number: 51113879-001 EN US 2021-10-27

2. PHYSICIAN'S TECHNICAL MANUAL VISIONIST™, VISIONIST™ X4, VALITUDE™, VALITUDE™ X4, INTUA™, INVIVE™, CARDIAC RESYNCHRONIZATION THERAPY PACEMAKER. Part Number: 359252-003 EN US 2018-03-01


Implantable Devices
Cardiac Resynchronization Therapy Devices
Important Safety Information

Cardiac resynchronization therapy pacemakers (CRT-P) and defibrillators (CRT-D) are designed to treat heart failure patients who may or may not have symptoms or who may have symptoms despite the best available drug therapy. They are also designed to help your heart pump more effectively and meet your body’s need for blood flow. These devices are sensitive to strong electromagnetic interference (EMI) and can be affected by certain sources of electric or magnetic fields. Some of the risks encountered during the implant procedure include, but are not limited to, the following: Bleeding, formation of a blood clot, damage to adjacent structures (tendons, muscles, nerves), puncture of a lung or vein, damage to the heart (perforation or tissue damage), dangerous arrhythmias, kidney failure, heart attack, stroke, death. Some of the risks encountered after the ICD system is implanted may include, but are not limited to, the following: Infection, erosion of the skin near your device, lead(s) may move out of place in the heart, device may move from the original implant site, difficulty coping with having an implanted device. The device might be prevented from shocking or pacing due to electromagnetic interference. Electrodes on the lead or the pacing pulses may cause an irritation or damaging effect on the surrounding tissues, including heart tissue and nerves. You may receive a shock or pacing therapy when it is not needed (unnecessary therapy). The device might not be able to detect or appropriately treat your heart rhythms. The device may exhibit malfunctions that may result in lost or compromised ability to deliver therapy. You may experience some discomfort from the incision as you recover from the surgery. With all medical procedures there are risks associated. In rare cases device failure or death can occur. Be sure to talk with your doctor so that you thoroughly understand all of the risks and benefits associated with the implantation of this system. To obtain a copy of the device Patient Handbook for more detailed device safety information, go to www.bostonscientific.com, or you can request a copy by calling 1-866-484-3268 or writing to Boston Scientific, 4100 Hamline Ave. N., St. Paul, MN 55112. Rx only

Device Quality and Reliability

It is Boston Scientific’s intent to provide implantable devices of high quality and reliability. However, these devices may exhibit malfunctions that may result in lost or compromised ability to deliver therapy. Refer to Boston Scientific’s CRM product performance report on www.bostonscientific.com for more information about device performance, including the types and rates of malfunctions that these devices have experienced historically. While historical data may not be predictive of future device performance, such data can provide important context for understanding the overall reliability of these types of products. Also, it is important that you talk with your doctor about the risks and benefits associated with the implantation of a device. 

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