Welcome to the Miami Transplant Institute’s Ventricular Assist Device Program. Ventricular assist devices (VADs) are mechanical heart support that prolong a patient’s life while waiting for a heart transplant. They are also known as a bridge to heart transplantation (BTT). VADs are usable for patients not eligible for a heart transplant and are known as a form of destination therapy (DT).
Besides extending a patient’s life, these devices can improve symptoms of heart failure, such as fatigue and shortness of breath.
About the Device
- What Is A Ventricular Assist Device?
- Who Could Benefit From This Device?
- What Types Of Devices Are Available?
- What Are The Components Of The VAD?
- What Should I Expect?
- How Long Can I Be Supported With An LVAD?
- Medical Decision-Making
- How Will I Know How To Care For The LVAD?
- How Are The Patients Selected For LVAD?
- What Are The Possible Risks Of The LVAD Implantation Procedure?
- Potential Complications
What Is A Ventricular Assist Device?
A ventricular assist device (VAD) is an implantable, artificial pump that assists the heart by pumping blood to the body. It aids the failing ventricle by taking some of the work load from the heart.
The surgeon connects the pump to the heart by using a tube that is made for this specific use. The blood travels from the heart, down the inflow tube and into the VAD. The VAD then pumps the blood into the outflow tube and delivers the blood to a major blood vessel. The pump is usually placed in the upper abdomen and cannot be seen.
The computer for the pump is outside the body and can be worn with a fanny pack or a belt clip. The pump and the computer are connected by a small cord that exits the body via a small opening on the side of the abdomen. The system can be powered by using batteries or by using an AC power adapter. The batteries enable the patient to resume most daily living activities.
VAD; RVAD; LVAD; BVAD; right ventricular assist device; left ventricular assist device; biventricular assist device; heart pump; left ventricular assist system; LVAS; implantable ventricular assist device
Most often, VADs are used in one of two ways to treat heart failure:
- As a “bridge to transplant,” a temporary implant used to help extend the life of someone waiting for a heart transplant.
- As “destination therapy,” or long-term treatment for patients who are not candidates for transplant, such as those with end-stage congestive heart failure. In these patients, the pumps are placed permanently to help the heart work better.
Who Could Benefit From This Device?
Patients who have end-stage heart failure who are no longer responding to medical management could benefit from a ventricular assist device (VAD). Generally, these are people with advanced heart failure who are considered Class III or IV by the New York Heart Association classification system. They may be transplant candidates who would receive a device as a bridge to transplantation, or if they are not candidates for heart transplantation, they may receive a device as destination therapy. The goal in both cases is to improve the quality of life as well as to prolong it.
A VAD is generally indicated in patients who:
• Were not helped by medical therapy
• Have end-stage heart failure
• Recently had heart surgery and need to reduce demand on the heart temporarily
• Are awaiting heart transplant and need a supplemental pumping mechanism to stay alive
• Are ineligible for other treatments but need long-term support for a weak heart
What Types Of Devices Are Available?
The Miami Transplant Institute’s Ventricular Assist Device Program offers various devices. The specific device that is best for you will be determined by your cardiologist and surgeon. Ventricular assist device (VAD) systems currently approved for bridge to transplant is Heart Mate II. There are also other VADs, for example, Heart Ware, which is under clinical trial, yet not approved by the Food and Drug Administration. Here are some of the options available to you at the Miami Transplant Institute.
Heart Mate® II
The Heart Mate® II is a new technology that utilizes rotor flow to propel blood from the left ventricle to the aorta. This device is used primarily as a left ventricular assist device (LVAD) and is a bridge to heart transplantation. The pump is approximately the size of a large candy bar and can be placed in smaller patients due to its compact size. It is an internal pump and is monitored by an external controller that is approximately the size of an adult’s hand. The patient carries the controller in a fanny pack. A patient utilizing this device is discharged from the hospital and can go back to work or school, and resume most daily life activities. The device is powered by an AC unit or by batteries.
MTI is currently participating in the next generation of VADs clinical studies, which provide more options for people with heart failure.
The Heart Ware
MTI is participating in the Heart Ware HVAD left ventricular assist device (LVAD) clinical trial. This device is a next generation LVAD that provides heart failure patients with up to 10 liters of additional blood flow, restoring a better quality of life in most cases. It is the size of a D-cell battery. The purpose of this study is to determine the safety and effectiveness of the Heart Ware VAD in patients with chronic Stage D/NYHA Class IIIB/IV left ventricular failure who have received and failed optimal medical therapy, and who are ineligible for cardiac transplantation.
What Are The Components Of The VAD?
Ventricular assist devices (VADs) come in a variety of sizes and types. The size of the device depends on its function. The type of VAD selected will depend on each patient’s individual needs and medical condition. The components of the VAD vary, according to the specific device used. In general, the device consists of a pump unit, which may be implanted in the abdomen or be outside the body, a control system and an energy supply.
When the unit is untethered, rechargeable batteries are used when the patient wants to be mobile. The batteries are changed as needed. The power base unit or alternate source is used to recharge the batteries. The controller and batteries can be worn in a belted waist pack or alternate carrying device.
What Should I Expect?
The pump is implanted during open-heart surgery that takes between 6 and 8 hours. You will be under general anesthesia for this procedure. There will be an incision at the mid-line portion of the chest that extends to the abdomen. Your circulation will be supported by the “heart/lung machine” so that your heart can be “stopped” for a short period of time while the pump is implanted. Once the ventricular assist device (VAD) is in place, the heart/lung machine will be stopped and the VAD, along with your heart, will resume the pumping of blood throughout your body. All incisions will be closed and you will be taken to an intensive care unit for recovery. You will be on a ventilator (breathing machine) after surgery. There will be a tube in your throat attaching you to the ventilator. You will not be able to talk as long as the tube is in place; however, you will be able to communicate by writing or other means. When your doctor determines it is safe, the ventilator will be turned down until you do all the breathing on your own. At that time, the breathing machine can be turned off and the tube in your throat removed. You will be receiving pain medication as you recover.
How Long Can I Be Supported With An LVAD?
Although implantation of a left ventricular assist device (LVAD) as destination therapy is considered permanent therapy, it is not considered a curative procedure for your heart problem.
The amount of time you can receive support from an LVAD is variable, depending on the type of system you receive and your medical condition.
One device and its components will not last you a lifetime. If it is not possible to repair your device, replacement may be necessary.
To enhance quality of life, patients with an LVAD must carefully follow the guidelines provided by their health care team.
We encourage you to create advance directives to let your doctor and others know your wishes concerning medical treatment in the event that you become unable to communicate.
If you already have advance directives, please review these documents to make sure that they still reflect your preferences, now that you are a candidate for destination therapy.
Under Florida law, there are two advance directives forms you can use to make your wishes known:
- Durable power of attorney: This form allows you to appoint someone as your agent to make all health care decisions for you, should you become terminally ill and unable to communicate, or if you become permanently unable to make decisions for yourself. You may want to choose an alternate agent in case the primary agent is unable to assist.
- Living will: This form allows you to give advance written directions about all of your health care decisions if you become terminally ill and unable to communicate, or if you are in a permanently unconscious state.
The ventricular assist device’s (VAD) power supply allows it to continue pumping without regard to your medical status. There may come a time when your medical condition or quality of life warrant that the device be turned off, and a living will can communicate your preferences to your health care providers.
Please share information about your advance directives with your surgical team.
How Will I Know How To Care For The LVAD?
A detailed education program will be provided to you and your caregivers to ensure safety and proper use of the device. Before you go home, you’ll need to know how to manage the device, including troubleshooting the device’s alarms and handling potential emergency situations. You’ll also need to demonstrate independence with self-care activities before you go home.
How Are The Patients Selected For LVAD?
To determine your eligibility for LVAD the following will be considered:
- Insurance approval/review
- Height, weight, body mass index (BMI), body surface area (BSA)
- Complete physical examination
- Full medical history including surgical reports of all heart surgeries and any other surgeries, allergy history, transfusion history, pregnancy history, vaccination history, smoking and alcohol history and substance abuse history
- Psychosocial evaluation by social worker
- Psychiatric evaluation if recommended
- Maximum oxygen consumption test (VO2) in ambulatory patient
- Assessment of right and left heart function by echocardiogram (ECHO)
- Right heart catheterization to asses right ventricular function and evaluate for irreversible pulmonary hypertension (high blood pressure in the lungs)
- Left heart catheterization with coronary angiogram; if left heart catheterization has been done at another center with in the previous six months, we may be able to obtain the report and films from that center. However, the procedure may need to be repeated if it doesn’t contain all the information we need.
- Chest computed tomography (CT)
- Pulmonary function tests (breathing tests to make sure your lungs function properly), including a room air arterial blood gas
- Lab tests:serological testing for HIV, hepatitis panel, comprehensive metabolic panel, BNP, lipid panel, PT / INR, PTT, TSH, CBC with differential, pre-albumin, PSA in males > 50 years old, HgbA1C
- Colonoscopy (if over age 50 and not previously done) or if you have risk factors for colon cancer
- Dental evaluation
- Carotid dopplers (a type of ultrasound study) if you have ischemic heart disease, known peripheral vascular disease, carotid bruit on exam or age over 50.
- Neuro-cognitive testing
- Additionally, other medical concerns that are found in the screening process will need to be pursued as appropriate. The intent is to fully evaluate all problems and potential problems.
What Are The Possible Risks Of The LVAD Implantation Procedure?
The risks of the left vetricular assist device (LVAD) implant procedure may include:
- Anesthesia complications, such as nausea, vomiting, allergic reaction to medications, sore throat from intubation, sleepiness, headache
- Sleep disturbances
- Emotional/psychosocial disturbances
- Pain or discomfort
- Development of blood clots/thrombus
- Multi-organ failure (lungs, liver, kidneys)
- Damage to the heart valves or other heart structures
- Device power source problems, or device malfunction, failure or movement of the device within your chest
- Leaks or tears at the cannula/graft connections
- Observable operation of the device (sound, vibration, alarms)
- Difficulty adjusting to the device
- Stroke or brain damage that may affect the thoughts, intelligence, movement, and/or the ability to see, hear, swallow, or move properly
- Hemolysis (breakdown of red blood cells)
- Dependence on mechanical ventilation (tracheostomy tube)
Special precautions are taken to decrease your personal risks.
However, there may be other possible risks. When you meet with your doctor, please ask questions to make sure you understand why the procedure is recommended and all of the potential complications.
The risks of destination therapy on a woman’s fetus are unknown, but device implantation can potentially burden the abdominal area due to the size and position of the device. Therefore, it is important that women of child-bearing potential use two forms of contraception (birth control) simultaneously for the duration of destination therapy, unless absolute abstinence is the chosen method.
Primary forms of contraception include your partner’s vasectomy, intrauterine devices, birth control pills and topical/injectable/implantable/insertable hormone birth control products. Secondary forms of contraception include diaphragms, latex condoms and cervical caps, each used with a spermicide.
Please be advised that contraceptive techniques, other than absolute abstinence, may not be 100 percent successful in preventing pregnancy. Please talk with your gynecologist about the forms of birth control that are right for you.
- High surgical risk for successful implantation
- Recent or evolving stroke
- Neurological deficits impairing the ability to manage device
- Non-cardiac terminal conditions such as metastatic cancer or cirrhosis
- Abdominal aortic aneurysm equal to or greater than 5 cm
- Biventricular failure
- Active systemic infection or major chronic risk for infection
- Severe pulmonary dysfunction FEV1 less than 1 L
- Multisystem organ failure
- Inability to tolerate anticoagulation
- Significant psychiatric illness or lack of social support
- Severe chronic malnutrition (BMI < 21 kg/m2 in male and <19 kg/m2 in females)
- Morbid obesity (BMI > 40 kg/m2)
- Chronic kidney disease with serum creatine level > 3.0 mg/dL
- Potentially reversible cause of heart failure
- Need for reoperation
After surgery, you will be taken to the intensive care unit for monitoring. Breathing tubes and IVs will be used to help the patient breathe and recover. Once stable — usually after about two to five days — he or she will move to a regular hospital room for two to four weeks of recovery. There are several medications you will need to take regularly, such a blood thinner to prevent the formation of blood clots in your ventricular assist device (VAD).
It’s very important to continue making healthy lifestyle changes before and after the left vetricular assist device (LVAD) implant procedure, including:
- Stop using tobacco
- Follow your recommended nutrition guidelines
- Stop drinking alcohol
- Don’t use illegal drugs
- Exercise regularly
If you need help making lifestyle changes, your health care providers can assist you with strategies or refer you to other resources such as a dietitian, smoking cessation specialist or cardiac rehabilitation program.