What is a left ventricular assist device?
Most women with heart failure caused by blood pumping problems (systolic heart failure) respond well to standard treatments and can enjoy a long, fulfilling life. However, some women continue to have severe heart failure symptoms even at rest, and any further loss of heart function could make the heart unable to support life.
The main definitive treatment option is a heart transplant. 10% to 20% of patients die while awaiting a heart transplant. To “buy time” while waiting for a donor heart to become available, these patients may receive a left-ventricular assist device (LVAD). An LVAD is a surgically implanted mechanical pump that helps maintain the pumping ability of a heart that can’t work well enough on its own. The device pulls blood out of the left ventricle and pumps it into the aorta, the main artery leaving the heart that distributes blood to the body. It can be thought of as an artificial replacement for the left ventricle, although it is actually just assisting the heart.
(Reprinted with permission from Thoratec Corporation)
The pump is implanted in the upper part of the abdomen. A tube attached to the pump comes out of the abdominal wall and attaches to a battery and control system outside the body. The devices are portable and can be used for weeks, months, or years while the patient waits for a transplant.
Because of the success of these devices, some women with severe heart failure may receive an LVAD device as a permanent treatment if they are not eligible for a heart transplant.
Who is eligible to receive a left ventricular assist device?
Women with advanced heart failure who continue to have severe symptoms even after all standard treatments have been used (Stage D heart failure) may be candidates for a heart transplant. A transplant may also be an option in women with limited blood flow to their heart who cannot have bypass surgery or angioplasty, or who have severe heart rhythm problems that were not fixed with a pacemaker or ICD.
Because their heart function has deteriorated so much, women with severe heart disease may not survive long enough for a donor heart to become available. An LVAD can keep the heart pumping while they wait for a transplant. LVADs can also be used for short-term treatment in women who have suffered major damage to their heart but are expected to recover (such as a severe heart attack, complications from heart surgery, or sudden heart muscle disease caused by inflammation).
If a heart transplant is not available, or if a woman is not eligible for a transplant (she may be too ill to survive the procedure) an LVAD is an option for final treatment with no plans for a transplant (called destination therapy). This is a relatively new use for the LVAD device, prompted by its success in treating patients waiting for a transplant. An LVAD will only be used in this way in women who are expected to die within a year if they receive only standard treatment.
How well does an LVAD work?
An LVAD improves survival in patients waiting for a heart transplant; in one study, 91% of patients were discharged from the hospital and 74% survived to receive their transplant.
A permanent LVAD device can also improve survival. In one early study of patients who received the device as destination therapy (no plans for a transplant), one in four patients survived another 2 years, compared with less than 1 in 10 patients who received only standard medical therapy. As devices and techniques improve, survival is likely to get better: a small recent study of newer devices found that 77% of patients survived for 2 years. An LVAD implant also avoids some of the complications of a heart transplant, such as the need to take medication to suppress your immune system and the possibility that your body will reject the transplanted heart.
Because an LVAD is only implanted in very sick patients, the risk of complications after the implant procedure is high. Stroke occurs in 16% of patients. However, patients who receive only medical treatment have an even higher stroke risk. Other serious complications can include bleeding and infection. The device may also fail to work properly, although most of the problems are repairable because parts of the device lie outside the body.
Since there have been only a few trials investigating the long-term effectiveness of this treatment, it is not know whether women and men benefit equally.
How do I prepare for the procedure?
As with other surgeries, your medication may need to be adjusted before having an LVAD implanted. Be sure to talk to you doctor about which of your medications you should and should not take, and whether you should change your dosing of blood thinners like warfarin (Coumadin), clopidogrel (Plavix) or aspirin.
The night before the procedure, you should not eat anything after midnight; this includes drinking water. If you need to take any pills the morning of the procedure, drink only a sip of water to take them.
Be sure to let your doctor or the anesthesiologist know if you have recently been sick or had an infection, or if you or a family member has ever had a bad reaction to anesthesia.
What happens during the procedure?
Implantation of an LVAD is performed via open-heart surgery in an operating room. You will be unconscious and under general anesthesia throughout the procedure. During the operation your heart rate, blood pressure, and oxygen levels will be continuously monitored.
Your chest will be opened with an incision along the breastbone. A tube will be inserted into the tip of the left ventricle (the main pumping chamber of the heart) and attached to the pump. Another tube will run from the pump to your aorta, where it will be sewn in place so the device can distribute blood to the rest of your body. The pumping chamber (new models can be as small as a “C” cell battery and weigh just 4 ounces) will be placed in your abdomen, and a tube will be led out through an incision in your stomach so the implanted parts of the LVAD can be connected to the parts you wear outside your body (a controller and batteries). This tube is covered in a special material that bonds to the skin, anchoring the tube in place.
The device will be tested to be sure it is working properly and your incision will be closed up.
(Reprinted with permission from Thoratec corporation)
What happens after the procedure?
After the procedure, you will stay in the hospital for a few days or weeks as you recover. Eventually you will start a rehabilitation program that includes walking and cycling to gradually improve your ability to perform exercise. If you are doing well enough you can be discharged home to await a transplant or live permanently with the device.
Your doctor will discuss with you what level of physical activity is appropriate and how to care for your wounds.
What is living with the device like?
Some women who have had an LVAD implanted are able to live at home, move around freely, and take part in many normal activities, including gardening, dancing, and driving. In one small study, 11 of 24 patients who received the device were able to return to school or work after the procedure. More research needs to be done on which patients do best after LVAD implantation.
You will have to wear a battery pack and controller for your device at all times, but these are designed to allow you to move easily. Because electronic parts of your device are worn outside the body, you will need to avoid activities that involve submersion in water, such as swimming or taking a bath. You will be able to shower after taking special precautions to protect the outer parts of your device.
Some patients who have an LVAD implanted even regain some of the normal function of their heart and are able to have the device removed.