Left Ventricular Assist Devices (LVADs)

A left ventricular assist device (LVAD) is a battery-driven pump surgically implanted to assist a heart that has become too weak from heart failure to pump effectively on its own. It works by pulling blood from a tube inserted into the left ventricle of the heart and then pumping it through another tube inserted into the aorta—the largest artery in the heart that is responsible for supplying most organs in the body with blood.

For several reasons, an LVAD is not considered a first-line treatment for heart failure but rather an option used when others haven't been effective. Implanting an LVAD is a surgical procedure that requires general anesthesia. What's more, although the pump is implanted inside the body, it connects to an external control device. Living with an LVAD requires certain lifestyle changes that many people would prefer to avoid having to make if possible.

Indications for Use

The ideal candidates for an LVAD are people whose condition has not improved with other aggressive medical therapy, such as those with:

• Severe chronic heart failure who are waiting for a heart transplant (Bridge-to-Transplantation)
• Severe end-stage heart failure who are not candidates for transplantation and have a poor prognosis without mechanical support, so they will retain the device for life (Destination Therapy)
• End-organ dysfunction due to heart failure but who may become eligible for a transplant with a stabilization of other organs (Bridge-to-the-Decision)
• A damaged left ventricle that needs to rest in order to repair itself after a cardiac surgical procedure, major acute heart attack, or acute myocarditis (Bridge-to-Recovery)

LVADs often are effective in restoring the amount of blood the heart is able to pump to near-normal levels, thereby reducing symptoms of heart failure—especially shortness of breath (dyspnea) and weakness. It also can improve the function of other organs that are affected by heart failure, such as the kidneys and liver.

Types

Left ventricular assist devices were developed in the 1990s. These first-generation versions attempted to reproduce pulsatile blood flow because it was assumed a pulse would be necessary for normal body physiology.

In time it became clear continuous blood flow was as effective as pulsatile blood flow, leading to the development of second-generation LVADs, such as the HeartMate II and Jarvik 2000, that are smaller, have only one moving part, and require less energy than their predecessors. They also last longer and are more reliable.

Third-generation LVADs are smaller still and designed to last for five to 10 years.

LVADs are entirely portable. The controller device is usually a bit larger than a cellphone. The batteries and controller devices are worn on a belt or chest strap.

How an LVAD Is Implanted

Implantation of an LVAD requires open-heart surgery and a hospital stay of several days. During the procedure, which may last from four to six hours, a surgeon will open up the sternum (the chest bone to which the ribs are attached) in order to access the heart.

Most LVADs consist of four main components, each of which is placed during the implantation surgery:

• Pump unit: This component is positioned in the apex of the heart where it receives blood. A tube attached to the pump delivers this blood to the aorta.
• Driveline: A cable that passes through the skin of abdomen and connects the pump on the inside of the body to the LVAD controller on the outside of the body.
• Controller: A small computer that controls the pump and can keep you apprised of how the LVAD is functioning
• Power supply: Either rechargeable batteries or a cord that plugs into an electrical socket

Contraindications

Not every patient whose heart needs assistance in pumping blood is a candidate for an LVAD. It is not recommended for those who:

• Cannot tolerate anti-coagulation therapy
• Have debilitating psychiatric disorders
• Have severe renal, pulmonary, liver, or neurological disease or evidence of advanced metastatic cancer
• Have right ventricular dysfunction, which may cause the device to malfunction
• Have had a heart attack leading to brain damage. Without adequate higher functions, LVAD placement increases the incidence of disease and decreases the quality of life.
• Have internal bleeding, especially due to blood-thinners or anti-clotting medications 

Risks and Considerations

Although there has been great improvement in the design and size of LVADs, there are still many problems associated with their use. These include:

• LVADs require meticulous daily maintenance and careful monitoring to make sure they are always attached to a good power source at night or when the user is napping
• As many as 30% of patients who have LVADs contract serious, sometimes fatal, bloodstream infections.
• Significant bleeding problems, occurring in between 30 to 60% of patients 
• The risk of stroke (from blood clots) is 17% at two years.

For someone with end-stage heart failure who isn't eligible for a heart transplant, a continuous-flow LVAD can be more effective at improving survival and quality of life than drug therapy.

However, they're likely to experience more adverse events. Although LVADs can improve survival and quality of life, the device itself and the surgery to implant are also very expensive, and may be out of reach for those who do not have insurance that will adequately cover the procedure.

Living with an LVAD

If you have an LVAD implanted, you will have to make certain lifestyle changes to accommodate the device:

• Always wear your LVAD equipment
• Always have a power source or access to an adequate electrical supply
• Dress and change the exit site of the LVAD daily
• Carry a bag with extra supplies with you at all times
• Take adequate precautions to protect the cables connected to your system controller and driveline
• Avoid swimming, baths, hot tubs, or any activity that requires that you submerse yourself in water
• Avoid contact sports
• Refrain from jumping
• Avoid magnetic resonance imaging (MRI)
• Stop smoking and/or drinking alcohol

A Word from Verywell

If you have end-stage heart failure, having a left ventricular assist device implanted to help your heart function may well be worth the considerable risks and inconvenience associated with placing and living with an LVAD. However, if your healthcare provider is recommending the device, be certain you understand all the pros and cons. Don't be afraid to ask as many questions as it takes to feel absolutely sure an LVAD is the right choice for you. If you're satisfied that it is, it will in all likelihood improve your quality of life.