The MedTronics InSync Congestive Heart Failure Pump

BHMC-LR is committed to bringing cutting edge technology to the people of Arkansas. Our cardiac program is proud to bring you resynchronization therapy for people who have heart failure and problems with electrical conduction in their hearts. Heart failure affects approximately 5 million Americans and is responsible for more hospitalizations than all forms of cancer combined.

In healthy people, the four chambers of the heart contract in synchrony to move blood through the body. However, in many patients who have heart failure, the electrical impulses that coordinate the contractions of the heart's chambers 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.

When the heart is not pumping properly, mild activity can cause shortness of breath or difficulty breathing, even when the person is lying down. The legs and ankles may swell as a result of increased water retention. People often feel weak and tired and may sleep more frequently.

The Medtronic InSync system is an implantable device and specialized leads designed to provide resynchronization therapy. The device sends tiny electrical impulses to both sides of the heart muscle of the lower chambers (ventricles). Resynchronizing the contractions of the ventricles is intended to help the heart pump blood throughout the body more efficiently. Cardiac resynchronization therapy, also known as biventricular pacing, is intended to complement, not replace, heart failure drug treatment and dietary modification.

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. 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.

Despite advancements in treatments, tens of thousands of heart failure patients suffer from two heart conditions that require separate therapies ¾ cardiac resynchronization and protection against fast heart rhythms. Medtronic InSyncâ ICD system is one device developed to treat both.

The InSync ICD device is an implantable device designed specifically to provide heart failure patients indicated for ICDs with both cardiac resynchronization therapy and defibrillation protection in a single device. The InSync ICD system is equipped with a special battery and sophisticated electronic circuitry designed to interpret signals from the heart, provide the actual pacing signals for cardiac resynchronization, collect diagnostic information, and send specialized impulses when needed to stop heart rhythms that are dangerously fast. To monitor the heart and provide the necessary electrical stimulation for cardiac resynchronization and defibrillation, three thin insulated wires (called leads) connect the InSync ICD device to the heart.

The cardiac resynchronization therapy improves the pumping efficiency of the heart, while the ICD function is often referred to as "an emergency room in the chest," protecting patients from potentially lethal heart rhythms using defibrillation therapies. Patients who receive cardiac resynchronization therapy often have more energy, a greater ability to exercise and perform daily activities, and a reduced number of hospitalizations from heart failure.

Resynchronizing – and Protecting – a Failing Heart: The Medtronic InSync® ICD

The Medtronic InSync® ICD device, implanted in the upper chest, is designed to resynchronize the pumping action of the heart's lower chambers as it protects the heart against dangerously rapid arrhythmias. In heart resynchronization therapy for heart failure, the physician programs the InSync ICD device to deliver electrical impulses at the precise times needed to make each chamber contribute to better pumping action. Other functions in the same device are programmed to monitor the electrical conduction system of the heart and to deliver corrective impulses when needed. Two leads – tiny insulated wires – carry impulses from the device through the vascular system to the inner walls of the right side of the heart. A third lead is threaded through the coronary sinus (middle of the heart) into a vein on the exterior wall of the left ventricle.

Of the 5 million patients in the United States diagnosed with heart failure, approximately 750,000 may be candidates for cardiac resynchronization therapy (CRT) available with the InSync system. Of those, an estimated 100,000 have a ventricular arrhythmia indication and could be candidates for the InSync ICD system, which is designed to additionally provide defibrillation protection – thus eliminating the need for multiple implants.

The InSync approved by the U.S. Food and Drug Administration in August 2001 provides resynchronization therapy for patients who do not require ICD therapies. The InSync ICD device provides both resynchronization therapy and defibrillation protection for those patients who are at high risk for potentially lethal ventricular arrhythmias.

A specially trained cardiologist (an electrophysiologist) or cardiovascular surgeon implants the InSync and InSync ICD systems. The devices are implanted under the skin in the chest area, and three very thin insulated wires (leads), with tiny electrodes on their distal ends, are maneuvered through a vein from the device to the heart: One lead is placed to touch the interior wall of the right atrium, another to touch the interior 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.