What Is a Cardiac Resynchronization Therapy Device?

A CRT device sends small, undetectable electrical impulses to both lower chambers of the heart to help them beat together in a more synchronized pattern. This improves the heart's ability to pump blood and oxygen to the body.

The heart device itself is actually a tiny computer, plus a battery, contained in a small titanium metal case that is about the size of a pocket watch. It weighs about 3 ounces.

In addition to the heart device, insulated wires called leads are implanted for two purposes: to carry information signals from your heart to the heart device, and to carry electrical impulses to your heart.

The third part of your implantable device system is a programmer, an external computer located in your doctor's office or clinic that is used to program the heart device and retrieve information from your heart device that will assist your doctor in your heart failure treatment.

There are two types of implantable heart failure heart devices: a CRT pacemaker and a combination CRT pacemaker with defibrillation therapy. Both of these devices help to coordinate the heart's pumping action and improve blood flow. They can also speed up a heart that is beating too slowly.

The CRT pacemaker with defibrillation therapy (CRT-D) also offers the ability to detect and treat dangerously fast heart rhythms, which some individuals with a damaged heart muscle may be at risk for developing. Your doctor will determine which CRT device is appropriate for your medical condition.