HEART
Heart Assist Devices
Dramatic advancements in medical therapy for heart failure have occurred. A new generation of smaller, more durable devices have emerged allowing patients with advanced end-stage heart failure that have exhausted all medical therapy to survive with ventricular assist devices. These surgically implanted, mechanical devices maintain the heart's pumping ability by supporting the left ventricle, right ventricle, or both.
Our heart transplant team has extensive experience implanting the Heartmate®, Thoratec®, and Abiomed® cardiac assist devices. Texas Transplant Institute is the only approved Destination Therapy Program in San Antonio that utilizes HeartMate® Left Ventricular Assist Device as a bridge to transplant or transplant alternative.
Understanding Cardiac Assist Devices
Pacemaker
Small battery-operated device used primarily to treat slow heart rates. The device monitors the heart rate and can send small electrical impulses to increase the heart rate if it senses that a heart rate is too low. Pacemakers are small metal devices that are placed in the upper chest with lead wires going to the heart; they are about the size of a pocket watch and can usually be implanted on an outpatient basis using local anesthesia.
Biventricular Pacemaker
In a large number of heart failure patients, the electrical impulses in the heart are slowed and the signals to one, or both, of the heart's lower chambers are delayed. If that happens, the two lower chambers may not pump at the same time. When the heart's contractions are out of sync, the heart cannot pump enough blood to the body. A special type of pacemaker called a "biventricular pacemaker" or "cardiac resynchronization therapy" can send electrical impulses to both lower chambers at the same time to coordinate the pumping function of the heart.
Implanted Cardioverter Defibrillator (ICD)
An ICD is an electrical cardiac device that is used to treat very fast heart rates and can stop life-threatening abnormal heart rhythms. The ICD monitors the heart rhythm at all times and will notice any abnormal rhythm. Within seconds, it can try to get the heart back into a normal rhythm by delivering painless pacing impulses or a more noticeable shock to the heart. ICDs are often used in patients who are at a high risk for sudden cardiac death due to their clinical history. The ICD is implanted into the upper chest with lead wires to the heart similar to a regular pacemaker. The procedure is often performed on an outpatient basis.
Ventricular Assist Device (VAD)
Some patients with very severe heart failure do not improve with medications only. If their heart continues to deteriorate and becomes unable to pump enough to sustain life, they may be offered a ventricular assist device for "Destination Therapy" or as a "Bridge to Transplant". During bridge to transplant, patients receive a VAD to support their heart while waiting for a donor heart. If they are not eligible for transplant, the VAD can provide long-term support for the patient's heart as destination therapy.
VADs are placed for pumping support of the left, right, or both chambers of the heart. A VAD is a pump that is surgically connected to the heart in two places to replace the pumping function of the existing heart. The pump itself may be placed in the patient's abdominal cavity or outside of the body. These devices are connected to an outside power source, but battery-powered connections are available to allow patients to go home from the hospital. Each device is different and will depend on the patient's body size and medical condition. Not every heart failure patient is eligible for a VAD. The patient must meet certain criteria of their overall health conditions, blood pressure, blood flow, and body size. Surgery to insert a VAD involves a variety of certain risks. If this therapy is recommended, your doctor will review the risks, benefits, and possible complications of this open heart surgery.