FDA today approved a new type of pacemaker that sends specially timed electrical impulses to the heart's lower chambers to treat the symptoms of moderate to severe congestive heart failure.
The device is the InSync Biventricular Cardiac Pacing System made by Medtronic, Inc., of Minneapolis.

The InSync system is the first pacemaker approved for treating the symptoms of congestive heart failure, a condition in which the heart can not adequately pump blood around the body. Standard pacemakers are used to treat rhythm disturbances in the heart, a different condition.

People with congestive heart failure typically experience fatigue and shortness of breath during exertion, and therefore have difficulty performing many of the routine tasks of daily living.

The InSync System consists of a pulse generator that is implanted in the chest and connected to the heart by three wires (leads) that deliver electrical impulses. One wire is placed in the upper right heart chamber and the others are placed in each of the two lower chambers, where they simultaneously stimulate both the left and right ventricles. This device differs from a standard pacemaker in that it has three leads instead of one or two leads.

FDA approved the product based on clinical studies of safety and effectiveness conducted by Medtronic and on the recommendation of the Circulatory System Devices Panel of FDA's Medical Devices Advisory Committee.

Medtronic studied use of the device in 579 patients with moderate to severe congestive heart failure at 44 medical centers in the U.S. and Canada. Patients were randomized to either having the pacemaker turned on or turned off and were followed for six months.

Overall, the majority of the patients in whom the pacemaker was turned on showed improvement in either quality of life scores, distance they were able to walk or their heart failure classification. Approximately one third of patients in the control group also saw improvement. There was no change in the mortality rates in the two groups.

The study did not reveal any major safety issues with the device itself; however, implanting the device requires special training on the part of the physician.

As part of the approval, Medtronic will be required to conduct a post-market evaluation of this device in 1,500 patients followed over three years.

Not all people with congestive heart failure have been shown to benefit from the new device. Patients who have not been helped by drug treatment and whose ventricles are not synchronized correctly are suitable candidates.