Treating Heart Failure

Heart failure is a chronic condition in which the heart muscle becomes weak and unable to effectively pump enough blood to meet the body's needs. According to the American Heart Association, roughly 5 million Americans have heart failure. About 550,000 new cases are diagnosed every year.

Heart failure usually develops slowly over time. Initially, patients may feel tired and short of breath during exertion. As the heart loses its ability to pump, the heart muscle enlarges and heart rate increases. This allows the heart to pump out more blood. However, eventually, the enlarged heart still can't keep up with the body's needs. Patients may feel tired and short of breath even during moderate activity - eventually, even at rest. Other symptoms can include chronic cough, wheezing, fatigue, loss of appetite, nausea, confusion and problems with thinking. Since the heart can't pump effectively, the chambers can't empty fast enough to accept blood coming back through the veins. This returning blood backs up, causing fluid to accumulate, most often in the legs and ankles.

Heart failure can occur at any age, but is more common in people over 65. It is also more common in African-Americans, people with a family history of an enlarged heart, and those with diabetes, high blood pressure, prior heart attack or heart valve damage.

Treating Heart Failure Patients with heart failure are often treated with a combination of therapies. Lifestyle modifications (like stopping smoking, losing weight, proper diet and avoiding alcohol) can help improve symptoms and may slow progression of the disease. Medications can improve blood flow by strengthening the heart or opening up blood vessels. Other drugs help eliminate excess fluid from the body. Underlying diseases that may be contributing to symptoms need to be controlled.

When medications and lifestyle modifications aren't effective enough, doctors may recommend surgery. A heart pump (left ventricular assist device, LVAD) can be implanted into the body to mechanically pump blood from the left ventricle (the main pumping chamber) to the body. Patients may also be candidates for a heart transplant.

The CardioVad™ LVADs are meant for temporary use - to buy time for patients until symptoms improve or a suitable donor heart becomes available for transplant. Permanent implantation is not typically recommended because insertion requires major surgery (which some patients with heart failure could not tolerate) and can cause bleeding, infection and development of dangerous blood clots. Internal parts may wear out, necessitating major surgery for replacement.

Researchers at the University of Chicago are testing a new type of device for patients with severe heart failure, called the CardioVad™. The device has three main components: a blood pump, a connector and a drive unit.

The blood pump is an inflatable bladder (similar to a deflated balloon) that is connected to the wall of the aorta (the main blood vessel leaving the heart). The connector (called the ViaDerm™ Percutaneous Access Device, or PAD) is a button opening over the skin. The underside of the button connects to a tube leading to the blood pump. On the outside, the button has a snap connection to attach a tube leading to the wearable drive unit. The drive unit consists of two battery-powered packs that can be worn in a vest or shoulder pack. The rechargeable batteries last for about 90 minutes. When at home, the patient can use a drive unit that is plugged into an electrical outlet.

The CardioVad works through a system called counter pulsation. When the heart relaxes after a beat, the CardioVad causes the internal bladder to inflate. The pressure displaces some of the blood in the aorta and forces it into circulation. As the heart contracts, or beats, the CardioVad deflates, creating suction that helps to pull blood from the heart's ventricle.

Traditional LVADs can decrease the workload on the heart by up to 100 percent. The CardioVad decreases the workload by about 50 percent. But doctors say there are many benefits of the new device. Placement of the CardioVad is easier on the patient than insertion of an LVAD. The heart isn't touched and only a small incision is needed to access the aorta. In many cases, patients are able to leave the intensive care unit in three days. The main working components of the CardioVad are located outside the body. So there are no internal parts to wear out and require replacement. Upgrades and repairs are done externally. The CardioVad also gives patients control over their condition. The device can be disconnected from the button snap while the patient is at rest and reconnected when extra assist is needed for the heart.

Currently, the CardioVad is in Phase I study at the University of Chicago. It is recommended for patients with class III or IV heart failure (moderate to severe symptoms) who don't benefit enough from traditional therapy and aren't candidates for a heart transplant.

For information about the CardioVad™ technology: http://www.lvadtech.com/

For general information on heart failure: American Heart Association, http://www.americanheart.org, or contact your local chapter Heart Failure Society of America, http://www.abouthf.org National Heart, Lung and Blood Institute, http://www.nhlbi.nih.gov