Left Ventricular Assist Device (LVAD)

A left ventricular assist device (LVAD) is a mechanical pump that is implanted in the left lower chamber of the heart, called the left ventricle. It functions to help pump blood from the left ventricle of the heart to the aorta (the large blood vessel exiting the left ventricle) which then carries blood to the rest of the body. When the heart’s left ventricle (main pumping chamber of the heart) is unable to pump blood efficiently, an LVAD helps restore healthy blood flow and prevent complications.

Working Mechanism of a Left Ventricular Assist Device

Your heart has four chambers, a left and right atrium and a left and right ventricle. Your left ventricle is responsible for pumping oxygenated blood from your heart to the major blood vessel that carries blood away from the heart, called the aorta. The job of the left ventricular assist device is to help your weakened left ventricle pump blood more efficiently.

An LVAD usually has 4 main parts: a pump, driveline, controller, and batteries.

• Pump: A tube is placed within your left ventricle. Blood passes through this tube, into a pump placed just under your heart, and into the aorta through another tube.
• Driveline: This is a cable that connects the pump to the controller. It passes through a hole in your abdomen.
• Controller: This powers the pump and gives you updates about whether the system is functioning correctly.
• Batteries: Two batteries power the controller when it is not plugged in. The batteries can be carried on a harness, belt, or backpack.

Indications 

Left ventricular assist device implantation is usually indicated to help manage end-stage heart failure. The heart is a fist-sized muscular organ that works around the clock, pumping blood to various parts of the body. End-stage heart failure occurs when the heart is unable to pump enough blood to meet the body’s needs. 

Heart transplantation is typically considered the gold standard for end-stage heart failure. Your surgeon may implant a left ventricular assist device, either to improve survival odds while someone is waiting for a heart transplant, or as a primary treatment if someone cannot get a heart transplant.

Preparation

Preoperative preparation for a left ventricular assist device may involve the following:

• A review of your medical history and a complete physical examination
• Routine diagnostic tests, such as blood work, ECG, echocardiography, and other tests specific to your condition
• Informing your doctor of any allergies to medications, anesthesia, or latex
• A review of your current medications and the need to discontinue certain medications for a specific period
• Refraining from solids or liquids at least 8 hours prior to the surgery
• Signing a consent form after the pros and cons of the procedure have been explained

Surgical procedure

Left ventricular assist device implantation is performed as an open-heart surgery, which takes several hours in the hospital. In general, the LVAD procedure will involve the following steps:

• General anesthesia is administered through an intravenous (IV) in your arm so that you sleep throughout the surgery and do not feel any pain.
• You will be connected to a ventilator, a machine that helps you breathe during the surgery.
• Medications are administered to stop the heart temporarily to connect you to a heart-lung bypass machine that performs the function of those organs during surgery.
• Your surgeon makes an incision down the middle of your chest and opens the breastbone, or sternum, to better view the heart in order to correctly place the device.
• The main pump is inserted into the tip, or apex, of the heart.
• The blood pumps through a flexible plastic tube to the aorta, which sends blood to the rest of the body.
• A cord is inserted through an opening in the abdomen to connect the pump to a control unit and battery pack outside the body.
• The incision is then closed with staples and sutures and a bandage is placed over the wound.

Postoperative care

After the surgery, you will be transferred to the ICU where you will remain on the ventilator until you are stable enough to breathe on your own. Your vital signs are monitored. Once the ventilator is removed you may start a liquid diet and gradually advance to solid foods. You will then be able to gradually resume your normal activities. Most often, pain medication, antibiotics, and blood thinners are given. Instructions on incision site care and bathing will be provided to help keep the wound clean and dry. You should avoid strenuous activities and heavy lifting for a defined period. Your physician will likely refer you to a cardiac rehabilitation program to help you increase your heart’s strength and endurance, and recover from your surgery. A follow-up appointment will be scheduled to monitor your progress.

Risks and Complications

Possible risks and complications of left ventricular assist device implantation include:

• Bleeding
• Infection
• Device failure
• Blood clots
• Heart failure
• Respiratory failure
• Kidney failure
• Stroke

Summary

A left ventricular assist device, or LVAD, is a small, battery-operated pump surgically implanted below the heart to treat end-stage heart failure. It helps the heart circulate blood more efficiently when it is no longer able to perform its natural function of pumping blood. LVAD surgery can significantly improve your symptoms and quality of life, and help individuals with advanced heart failure return to a more normal life.