Some patients with heart failure will be eligible to receive one of several types of assistive devices that can be implanted in the body to help improve the heart’s pumping ability. In heart failure, the heart muscle cannot pump enough blood to meet the body’s needs for oxygen and nutrients. Because of the widespread prevalence of heart failure and expected increases in the number of heart failure patients as the Baby Boomers age, researchers are always looking for new technologies—or improvements on older technologies—to help patients.
Cardiac Resynchronization Therapy (CRT)/Biventricular Pacemaker, or Implantable Cardiac Defibrillator (ICD)
Your heart has a natural electrical system that regulates the speed and timing of how the heart’s chambers expand and contract to push blood through the chambers. This process creates your heartbeat. With heart failure, the heart can sometimes beat in an unsynchronized fashion. Doing so decreases the effectiveness of the heart. A CRT/biventricular pacemaker is a device that is implanted under the skin, with two or three wires passing through the veins leading to the heart muscle. A biventricular pacemaker has wires in the left and right lower chambers of the heart and times the impulses to make the heart muscle contract in better “sync” and improve the overall pumping function.
An implantable cardiac defribrillator (ICD) has the same function as the paddle defibrillators you may have seen used on patients in television shows or movies. If the heart goes into cardiac arrest and is in a dangerous rhythm (ventricular fibrillation or ventricular tachycardia), the ICD shocks the heart muscle back to a normal heart rhythm.
A biventricular pacemaker and ICD can be combined into one device that is implanted beneath the skin in the chest. ICDs have been shown to reduce the risk of cardiac arrest in heart failure patients who have a low ejection fraction (a measure of how much blood your heart’s pumping chambers expel with each contraction). CRT/ICD devices have been shown to reduce mortality and improve quality of life in appropriately selected patients.
Left Ventricular Assist Device (LVAD)
A left ventricular assist device (LVAD) is a mechanical device that helps to pump blood from the heart’s main pumping chamber (left ventricle) to the aorta (the main artery coming out of the heart). By taking over some of this functioning from the heart, the pump allows the heart muscle to rest and even recover in some cases. An LVAD can relieve symptoms such as fatigue and difficulty breathing for heart failure patients.
Implantation of an LVAD in the chest requires open-heart surgery. The pump is connected to the existing heart muscle and does not replace it. The pump is connected via a cord through the skin to an external, wearable control unit on the outside of your body. Batteries that are also worn on the outside of the body power the control unit and pump.
LVADs are used in patients who are waiting for a heart transplant. They are sometimes also used after open-heart surgeries to allow the heart muscle to rest. LVADs have been shown to increase survival rates in heart failure patients.
Percutaneous Heart Pumps
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The Impella is a tiny heart pump that can be implanted without open heart surgery. The pump supports the heart, allowing the heart muscle to rest and recover, especially after a major heart event. When Curtis Broome’s heart stopped and he went into cardiogenic shock, his cardiologists implanted an Impella to stabilize his heart, ultimately helping him survive and avoid a heart transplant. Watch Curtis’s amazing story here.
While an LVAD consists of thick tubes and a pump connected externally to the heart muscle and aorta, percutaneous heart pumps place a much smaller tube inside the heart’s chambers. These tiny heart pumps are placed in the heart via a thin tube called a catheter that is threaded through a puncture site in the skin. Open-chest surgery is not required for placement of a percutaneous heart pump.
Two common pumps are the Impella and TandemHeart. The Impella pulls blood from the left ventricle through the catheter and ejects it into the aorta. The TandemHeart takes oxygenated blood from the upper left chamber of the heart (left atrium) and deposits it in the femoral artery in the leg to be circulated throughout the body.
The Impella pump assists the heart’s normal circulation, while the TandemHeart essentially bypasses it. In so doing, these tiny pumps allow the left ventricle of the heart (the main pumping chamber) to rest. As with LVAD, in some cases percutaneous heart pumps can help the heart muscle recover.
Implantation of these pumps is still uncommon and is for end-stage heart failure patients. These two devices are generally used on a short-term basis.
If you have heart failure, you will be part of a care team that includes a number of healthcare professionals and caregivers from among your family and friends. Together, you’ll explore your options, including lifestyle changes, medications and treatment options. It may help to read these articles about living with heart failure.