DEAR DOCTOR K:
I have severe heart failure. My doctor wants me to consider an LVAD. What do I need to know?
Heart failure is a condition in which the heart cannot pump efficiently enough to meet the body’s need for blood. It needs help; it’s too weak to do the job. Medicines can strengthen the heart, but only to some degree. Ultimately, the only solution may be a heart transplant.
What about when medicines aren’t enough, and there isn’t a heart available to be transplanted? Increasingly, left ventricular assist devices (LVADs) are being used as a “bridge” to transplantation.
An LVAD is a battery-driven pump that is implanted in the chest. It pumps oxygen-rich blood around the body. In so doing, it helps perform some of the work that normally must be done entirely by the left ventricle (the bottom left chamber of the heart). In other words, it helps take the load off the left ventricle.
An LVAD consists of a pump, a control system and an energy supply. The pump can be located inside or outside the body. The control system and energy supply remain outside the body. (I’ve put an illustration showing how an LVAD works below.)
How the LVAD works
A left ventricular assist device (LVAD), a battery-driven pump implanted in the chest to support the pumping action of the left ventricle, helps move blood into the aorta. The machine consists of a pump, a control system, and an energy supply. The pump can be located inside or outside the body, while the control system and energy supply consoles are outside the body.
A heart transplant can be performed only when there is a healthy heart available. For that to happen, someone must have died of something other than heart disease and have a healthy heart. Furthermore, that person must have agreed in advance to allow their heart to be given to someone else, should they die. Finally, the potential donor must be immunologically similar to the person who needs the heart. If not, a transplanted heart would be rejected by the recipient’s immune system.
Because of problems with the availability of organs for transplantation, 18 people die each day waiting for organ transplants. LVADs help keep some people alive until a donor heart becomes available.
Other heart failure patients may not qualify for a heart transplant because of medical conditions that disqualify them. For these patients, an LVAD may be used to lighten the extra burden on the heart and give them more time. With this additional support, the other conditions may improve enough for the person to become a transplant candidate.
In the future, I expect that LVADs will increasingly be used as a permanent alternative to transplantation. But they do carry serious risks. For example, an infection can develop where the line to the battery pack exits the skin. In addition, blood clots can form. This requires ongoing use of blood-thinning medications. But these drugs, in combination with other changes caused by the LVAD, increase the risk of excess bleeding. The dual hazards of clotting and bleeding increase the risk of stroke.
Despite these potential risks, LVAD technology is continually improving. Fortunately, you have available to you today a treatment that was not available several decades ago. I wish you the best.