A VAD, or ventricular assist device, is a mechanical pump surgically implanted in the chest to help a weakened heart pump blood. It doesn’t replace the heart. Instead, it works alongside it, taking over much of the pumping work that a failing heart can no longer handle on its own. VADs are most commonly used in people with advanced heart failure, either to keep them alive while waiting for a heart transplant or as a long-term treatment when transplant isn’t an option.
How a VAD Works
A VAD has three main parts: an internal pump placed inside the chest, a thin cable (called a driveline) that exits the body through a small opening in the abdomen, and an external controller with battery packs worn outside the body. The controller manages the pump’s speed and monitors its performance.
For the most common type, a left ventricular assist device (LVAD), the pump connects to the bottom of the heart’s left ventricle. Blood flows from the ventricle into the pump, which then pushes it out through a tube connected to the aorta, the body’s main artery. This effectively takes over the left side of the heart’s job: delivering oxygen-rich blood to the rest of the body. Modern pumps use a spinning internal rotor to move blood in a continuous stream rather than mimicking the heart’s natural pulse, which means some VAD patients have little or no detectable pulse in their wrist.
Types of VADs
There are three configurations, depending on which side of the heart needs help:
- LVAD (left ventricular assist device): The most common type by far. It supports the left ventricle, which pumps oxygenated blood out to the body.
- RVAD (right ventricular assist device): Supports the right ventricle, which sends blood to the lungs to pick up oxygen. RVADs are far less common and typically used temporarily after heart surgery.
- BiVAD (biventricular assist device): Assists both sides of the heart. This is reserved for patients whose heart failure affects both ventricles severely.
The HeartMate 3 is currently the primary LVAD in clinical use. It’s a small centrifugal pump approved by the FDA for both bridge-to-transplant and long-term (destination) therapy. An older model, the HeartMate II, used a different internal design and is still functioning in some patients. Medtronic’s HeartWare HVAD has been discontinued due to safety concerns, though some patients still have one implanted. For short-term emergencies, temporary devices like the Impella can be inserted through a blood vessel without open-heart surgery to stabilize a patient until a more permanent solution is available.
Who Gets a VAD
VADs are used in three main scenarios, each with a different goal:
Bridge to transplant. The patient is already approved and listed for a heart transplant but is too sick to wait safely without mechanical support. The VAD keeps them alive and functional until a donor heart becomes available, which can take months or even years.
Destination therapy. For patients with end-stage heart failure who aren’t candidates for transplant, whether due to age, other medical conditions, or personal choice, a VAD becomes a permanent treatment. These patients typically have a heart pumping at less than 25% of its normal capacity and haven’t improved despite aggressive medical therapy for at least 45 of the previous 60 days.
Bridge to recovery. In some cases, a VAD gives the heart enough rest that it partially or fully recovers its own pumping ability. When that happens, the device can potentially be removed. This is the least common scenario but does occur, particularly in certain types of heart muscle inflammation.
The Surgery and Recovery
VAD implantation is open-heart surgery performed under general anesthesia. The surgeon places the pump inside the chest, connects it to the heart and aorta, and threads the driveline cable out through the skin of the abdomen. Most patients spend four to five days in the ICU afterward, with a total hospital stay averaging two to three weeks. During that time, the care team trains the patient and their caregivers extensively on how to manage the device at home, including driveline wound care, battery swaps, and responding to controller alarms.
Daily Life With a VAD
Living with a VAD requires real adjustments, but most patients describe the tradeoff as worthwhile compared to the severe limitations of end-stage heart failure. Each morning starts with disconnecting the controller from wall power and connecting it to freshly charged battery packs. Two full batteries typically last 8 to 12 hours, so carrying spares is essential any time you leave the house. At home or work, plugging the controller into a wall outlet saves battery life.
Showering is possible with a special waterproof bag that protects the controller and the driveline exit site, but baths, swimming, and anything that submerges the equipment are off limits. The driveline exit site on the abdomen needs daily cleaning and dressing changes to prevent infection. At bedtime, you plug the controller back into wall power and set the batteries on their charger for the next day.
Patients wear the controller and batteries in a vest, belt, or shoulder bag. The equipment adds a few pounds of weight. Travel is possible but requires planning: extra batteries, a backup controller, and awareness of power sources. Many patients return to work, drive, and exercise at moderate intensity, though contact sports and heavy lifting are restricted.
Risks and Complications
VADs are life-saving, but they carry significant risks that persist for as long as the device is in place.
Bleeding is the most frequent complication, affecting 30% to 60% of patients. The continuous-flow design of modern pumps can break down a blood protein involved in clotting, and patients also take blood-thinning medication to prevent clots from forming inside the device. This combination makes gastrointestinal bleeding especially common, occurring in up to 60% of LVAD patients. Those who experience one GI bleed are at high risk for repeat episodes and more frequent hospital readmissions.
Infection at the driveline exit site is the other persistent concern. The cable that passes through the skin creates a permanent opening where bacteria can enter. Smaller drivelines in newer pumps have reduced but not eliminated this risk. Meticulous wound care is the primary defense.
Stroke is a serious possibility. In a large registry of over 18,000 LVAD patients, neurological events occurred in 13% to 20% of patients within the first year, depending on the pump type. Blood clots forming inside the pump itself (pump thrombosis) have become less common with newer technology. In clinical trials of the HeartMate 3, confirmed or suspected pump thrombosis occurred in only 1.4% of patients at two years.
Survival Rates
Outcomes have improved substantially with each generation of VAD technology. Data from the ELEVATE registry, which tracks HeartMate 3 patients, shows a two-year survival rate of 83.4% for patients receiving the device as their first implant. At five years, survival was 63.3%. For context, patients with the severity of heart failure that qualifies for a VAD have a one-year survival rate well under 50% with medication alone.
Survival free of major complications (no stroke, no pump clot, no significant bleeding requiring intervention) was 43.8% at five years. That number reflects the reality that while most patients survive, many will deal with at least one serious complication along the way.