Heart failure ( HF) is a major cause of morbidity and mortality that raises healthcare costs and leads to deterioration of quality of life, with a prevalence of nearly 23 million people worldwide. Despite survival advances resulting from improved medical treatments and improved medical approaches for sudden cardiac death, a section of patients with progressive heart failure continue to require heart transplantation (HTx) or long-lasting mechanical assistance, for instance, Left Ventricular Assist Devices (LVAD) to prolong their lives. Heart transplantation remains the gold standard for adults with end-stage heart disease. Nonetheless, due to the paucity of the donor’s hearts and the rising multiple contraindications, this choice only applies to a fraction of patients.
A Ventricular Assist Device (VAD) is a form of durable mechanical circulatory support that partially replaces the failing heart function. Over the last decade, the use of LVADs has steadily increased since their initial approval for use as a bridge-to-transplant (BTT). Second and third-generation LVADs have achieved enhanced reliability by using wear-free materials, facilitating the upgrading of LVAD usage to a Destination Therapy (DT) strategy in patients who are unable to undergo Heart Transplantation. LVADs offer major clinical benefits for patients and extend their life but as every good thing comes with a tiny drawback, LVAD’s are not free from complications.
When talking about Heart Failure, the heart becomes weak and can’t maintain adequate blood flow to meet an individual’s body requirement. Its effects are worse and the affected patient can barely walk, talk, or even lie down supine. The terminal stage patients are recommended to undergo an LVAD implantation. This is a small pumping device operating on rechargeable batteries. The pump is implanted just below the heart in the thoracic region while the batteries are outside. Once implanted, it takes over the entire blood pumping function of the heart and the patient gets a new lease on life along with a few lifestyle constraints. It can also be used as a “bridge to transplant,” i.e. to hold the patient safe before a heart is available for transplantation. It can also be used as a “destination treatment,” making it a permanent option for patients not suitable for transplantation.
In patients with advanced heart failure, prompt referrals for transplantation, and left ventricular assisting device implantation plays a key role in favorable outcomes. Nonetheless, diagnosis typically takes place at specialized centers for heart failure and is blurred by referring physicians. This means that the decision making candidacy for advanced treatment and the potential impact of the new organ allocation algorithm plays an important role in planning the treatment.
Ventricular Assistive Device (VAD)
An implantable mechanical pump that helps transfer blood from the lower chambers of your heart (the ventricles) to the rest of the body is a ventricular assist device (VAD) — also known as a mechanical circulatory support system. A VAD is used in people who have a Heart Failure or weakened heart. While a VAD can be put in the heart’s left, right, or both ventricles, it is most commonly found in the left ventricle. When put in the left ventricle it is called a left ventricular assist device (LVAD).
You may have a VAD implanted while awaiting a heart transplant or waiting for the heart to become powerful enough to pump blood efficiently on its own. When you have heart failure and are not a suitable candidate for a heart transplant, your doctor can also consider getting a VAD implanted as a long-term treatment. A VAD implant procedure also involves open-heart surgery and has significant risks. However, if you have serious heart failure a VAD may be life-saving.
Left Ventricular Assist Device (LVAD)
LVAD or left ventricular assist device is an implantable mechanical pump that is used to support end-stage heart failure patients to support the left ventricle pump blood to various areas of the patient’s body. It is a small mechanical circulatory support system, which operates on a battery and is surgically positioned inside the heart of the patient. This may be used as the destination treatment for non-transplant-eligible patients.
Unlike a completely artificial heart, LVAD does not replace the heart, but rather it only allows the heart to perform its functions more effectively and without much pressure. The system will help postpone the need for a heart transplant. Hence, it helps keep the patient alive before an effective donor is identified.
For patients undergoing a heart transplant, this is a life-saving treatment. Patients use LVAD until they find a donor. The LVAD in some cases will restore the failing heart, removing the need for a transplant. Learning more about heart transplantation, The FDA approved the LVAD system in 2008 for patients undergoing a heart transplant.
While patients wait for their transplantation, their heart and health condition may begin to worsen, leading to hospital admission, increased complications, and damage to other organs such as the kidneys, liver, and lungs.
When a patient becomes a heart transplant recipient, bridge-to-transplant treatment can help the patient survive before a donor ‘s heart is available. The LVAD protects the heart and encourages the patient to have a better quality of life and fewer complications, and is then extracted at transplantation.
The amount of time you receive support from a VAD before heart transplantation varies, which depends on your condition, source of blood, and size of the body. Currently, FDA approved for BTT are the Heartmate III, HVAD, and Heartmate II.
Many patients do not require a heart transplant. In this situation, patients can use an LVAD to seek long-term care which can extend and enhance the lives of patients. In 2010, the FDA approved the patient-destination therapy (DT) LVAD system for heart failure patients who were not eligible for heart transplant surgery. It is only considered for patients when all other treatment options, such as medicine, lifestyle changes, and cardiac operations, have been tried and have not been effectively managed.
DT’s goal is to help the heart function of the patient and enhance the quality of life for the remainder of the patient’s life.
The doctor will decide if destination therapy is an appropriate treatment choice for you, based on your medical condition, symptoms, body size, and other conditions.
For certain patients with blood clotting disorders, permanent kidney failure, serious liver disease, severe lung disease, or infections that can not be controlled with antibiotics, destination therapy may not be the best treatment option. Currently, FDA approved for DT are Heartmate III, HVAD, and Heartmate II.
LVAD has three main components-a pumps, a power generator, and an external battery. The pump is implanted surgically close to the heart with one part connected to the left ventricle and the other end to the aorta. Blood from the ventricles flows into the pump and passes into the aorta. A pump cable exits your body through a cut in the abdomen which connects outside the body with the controller and the battery.
Left Ventricular Assist Device (LVAD) is designed to enhance the survival of end-stage heart failure patients and their quality of life. Left Ventricular Assist Device (LVAD) is a mechanical pump that is connected to the heart and is surgically implantable.
An LVAD is not the same as the artificial heart. The artificial heart fully covers for the failing heart and an LVAD works with the heart to help it pump more blood with less effort. This is achieved by constantly taking blood from the left ventricle and then transferring it to the aorta, which then provides oxygen-rich blood in the body. The device is mounted in the left ventricle (main heart chamber) to pump oxygen-rich blood all over the body. The LVAD includes internal as well as external components. The main pump is located on or next to the left ventricle of your heart, with a tube attached to route the blood to your aorta. A cable called the driveline passes through the skin from the pump and links the pump to a controller and power sources that are worn outside the body.
The LVAD is distributed in three categories like:
Short term: In patients with severe complications and unable to sustain long-term life.
Intermediate-term: Up to 500 days for patients with severe complications
Long-term: For patients suffering from advanced heart failure who require care outside the hospital.
Indications for LVAD
Left ventricular assist devices can be used to benefit patients with a broad variety of chronic heart problems. It includes:
- Serious symptomatic cardiac failure
- A shock from postpericardiotomy
- Serious ventricular dysfunction in the left
- Progressive heart failure with effective medical treatment
- Patient awaiting transplant
- Heart failure along with other organ dysfunctions
Conditions Treated with LVAD
LVADs treat patients with advanced heart failure conditions. The patients include the ones :
- Are too old to undergo heart transplantation.
- Wants to undergo transplantation but are not stable enough to wait for a donor’s heart.
- Had a massive heart failure episode and left with no other treatment options.
- Are having a very high body mass index (BMI) to undergo a heart transplant
- Have advanced stages of Myocarditis or Dilated Cardiomyopathy
- Have a health issue that precludes heart transplant.
- Have experienced organ rejection especially after heart transplantation.
- Have undergone heart surgery but are not in a condition to be removed from cardiopulmonary bypass.
Various Diagnostic Tests that doctor may suggest before LVAD
The doctors may conduct several tests like:
- Metabolic stress test
- Cardiac MRI
- Cardiac Catheterisation
- CT Scan
- Chest X-ray
- Blood test
All these tests are performed prior to the transplant in our specialized labs.
Cost of LVAD in India
Previously, LVADs were used as a ‘bridge-to-transplant’ before a corporeal donor was available. These LVADs were costing in the range of USD 30.000-60.000. However, these days, LVADs are also available at Destination Therapy (DT) which acts as a heart for the rest of life. The costs of DT LVADs could be almost double of the former.
LVAD as an alternative to heart transplant
Doctors and patients now consider it a viable alternative, rather than a heart transplant. This gains popularity even more as the donor’s hearts are in short supply, and the patient will live with the unit. This permits regeneration quicker than a heart transplant operation. The device’s life expectancy is 60 years, as per FDA approval.
LVADs are now more compact and can be implanted in adults and children alike. Furthermore, the manufacturers are working on a miniature unit that can be put entirely within the body, thereby reducing the hassles of wearing a part outside.
The following are 10 points to remember about left ventricular assist devices (LVADs) as a rapidly evolving alternative to transplant:
- LVADs have been used as a bridge to heart transplant for those who qualify for transplant (path to transplant) or as a replacement for those who do not (destination therapy), where there are chronic donor shortages and a growing number of patients with Stage D heart failure.
- Given ongoing steps to expand access to donor organs, the availability of organs remains a significant limitation for heart transplants.
- The current strategy for the management of refractory Stage D heart failure with reduced ejection fraction (HFrEF) patients is to initially screen for a heart transplant, with destination therapy VADs considered as a secondary treatment for those who do not qualify.
- There might be a need to reconsider the existing method for screening patients for advanced HF therapies, with a change to considering patients initially for destination VAD and heart transplant reserved for selected patients or as bailout treatment.
- VAD supports improved quality of life and longevity relative to conventional treatment, with a 2-year performance equivalent to a heart transplant in some cases. More LVAD implants are performed per annum now than heart transplants.
- LVAD complications remain and may have lessened interest in less ill patients for exploring LVAD therapy; however, technology continues to advance rapidly.
- Smaller devices, complete implantability, pulsatility, and remote control are being studied and the application of VAD technology will be broadened.
- Clinical trials are required to decide which patients are most benefiting from LVAD support versus heart transplant.
- LVAD technology is rapidly evolving, and its accessibility is growing in comparison with heart transplants.
- In the future, initial therapy for Stage D HF may be considered as VADs, with heart transplant reserved for VAD failures and selected patients.