Cardiac resynchronization therapy

Cardiac resynchronization therapy is a new treatment for heart failure that uses an implantable device to improve the pumping efficiency of the heart. 

In healthy people, the four chambers of the heart contract in synchrony to move blood through the body (people experience this as their heartbeat). However, in many heart failure patients, the electrical impulses that coordinate these contractions may be impaired. As a result, in up to 50 percent of people who have advanced heart failure, the two lower chambers, called ventricles, no longer contract at the same time. This may worsen the symptoms of disease, which include shortness of breath, fatigue, and swelling of the feet and ankles.

In cardiac resynchronization therapy, a device is implanted in the upper chest in an attempt to resynchronize the contractions of the ventricles by sending tiny electrical impulses to the heart muscle. Resynchronizing the contractions of the ventricles can help the heart pump blood throughout the body more efficiently and reduce the symptoms.

Cardiac resynchronization therapy, also known as biventricular pacing, is intended to complement standard drug treatment, and dietary and lifestyle modifications.

Is surgery required to implant a resynchronization system?

Yes. a specially trained cardiologist or cardiovascular surgeon implants the system. The device is implanted under the skin in the chest area, and three very thin insulated wires (called leads), with tiny electrodes on their ends, are maneuvered through veins from the device to the heart. One lead is placed to touch the inner wall of the right atrium, another to touch the inner wall of the right ventricle and the third lead is threaded through the coronary sinus and placed to touch the outer wall of the left ventricle.

The implantation procedure is typically done with local anesthesia, so the patient remains conscious. However, the procedure takes longer than a typical pacemaker implant because of the need to implant the third lead to pace the left ventricle. Patients usually stay in the hospital overnight.

What are the potential benefits of this therapy?

For those patients with heart failure who have electrical conduction problems of the heart, resynchronization therapy is intended to improve the heart’s efficiency and increase blood flow to the body. Blood ejected from the heart is decreased in people who have heart failure, which is the reason they often experience symptoms such as fatigue, shortness of breath, and swelling (or edema) of the feet and ankles. By improving blood flow, heart resynchronization therapy may reduce heart failure symptoms, improve quality of life and increase patients’ ability to perform the tasks of daily living.