A Left Ventricular Assist Device (LVAD) is a mechanical pump designed to support the function of a failing heart. This battery-operated, surgically implanted device takes over a significant portion of the work previously done by the heart’s main pumping chamber, the left ventricle. Its primary role is to ensure a continuous and adequate flow of oxygenated blood to the rest of the body. The LVAD allows the weakened heart muscle to rest while maintaining the necessary circulation for vital organ function.
The Need for Mechanical Support
The need for an LVAD arises in patients with severe, end-stage heart failure. In this condition, the heart muscle is too weak to pump enough blood to meet the body’s demands. Specifically, the left ventricle fails to generate sufficient pressure, leading to low cardiac output. This inadequacy causes fluid buildup in the lungs and reduces blood flow to vital organs like the kidneys and brain.
Patients experience fatigue, breathlessness, and a decline in their quality of life as the heart loses its ability to contract forcefully. At this advanced stage, traditional treatments like medication are no longer effective. The LVAD intervenes mechanically to restore sufficient blood flow. This action mitigates the symptoms of organ distress and systemic congestion.
How the LVAD Works
The LVAD system works to bypass the function of the weakened left ventricle. The main pump unit, a small, continuous-flow turbine, is implanted directly into the chest near the apex of the left ventricle. An inflow cannula draws blood from the left ventricle and directs it into the pump’s spinning rotor.
The continuous-flow design minimizes friction and wear, allowing the pump to spin at high speeds. The blood is then propelled through an outflow graft, a flexible tube connected to the ascending aorta, the body’s main artery. Because the device continuously moves blood into circulation, supplementing the heart’s native pumping action, a patient with an LVAD may have a very weak or even undetectable pulse.
The internal pump connects to external equipment via a percutaneous driveline. This cable exits the body through a small opening, usually in the abdomen. The driveline connects to a controller, which is the external computer that monitors pump speed, manages alarms, and draws power. The controller is powered by battery packs or an electrical outlet, requiring the patient to carry the power source at all times for uninterrupted support.
Purposes for Implantation
The decision to implant an LVAD is based on the patient’s long-term prognosis and eligibility for a heart transplant. While the mechanical function of the device is the same in both cases, the clinical purpose dictates the long-term management and psychological preparation required for the patient and their care team.
Bridge to Transplant (BTT)
This strategy provides temporary life-sustaining support for a patient awaiting a donor heart. The LVAD stabilizes the patient’s condition, reverses organ damage caused by heart failure, and improves physical status until transplantation is possible.
Destination Therapy (DT)
DT is a long-term solution for patients who are not candidates for heart transplantation due to age or co-existing medical conditions. For these individuals, the LVAD is intended to be the final therapy, providing years of improved survival and quality of life.
Living with an LVAD
Life with an LVAD requires device management and lifestyle adjustments to maintain function and minimize complications. Patients and caregivers must manage the external components, including changing battery packs and responding to alarms. Meticulous daily care of the driveline site, where the cable exits the body, is required to prevent infection, which is a serious risk.
Due to the device’s continuous pumping action and the foreign material within the bloodstream, patients must adhere to a strict regime of continuous anticoagulation therapy. This is necessary to prevent blood clots from forming inside the pump or causing a stroke. However, blood thinning increases the risk of serious bleeding events, particularly in the gastrointestinal tract. Frequent monitoring by a specialized medical team is required to balance preventing clotting and avoiding excessive bleeding.
Physical activity is encouraged to rebuild strength. Mandatory lifestyle limitations include avoiding water immersion activities, such as swimming and bathing, to protect external components. Patients must also avoid contact sports that could damage the driveline. Despite these adjustments, the LVAD restores functional capacity, allowing patients to return to many aspects of a normal life.