Artificial Heart vs Heart Transplant in Heart Failure

The choice between an artificial heart and a heart transplant arises when heart failure no longer responds to medicines and the heart is too weak for any corrective operation. The artificial heart is a left ventricular assist device (LVAD). Dr. Ajay Kaul, Chairman Cardiac Science, Fortis Hospital, Noida, India, regards transplant as still the best treatment, with the artificial heart carrying patients through the wait for a donor.

This article sets out how the two options compare: when each is used, how the artificial heart works, its complications and expected lifespan, what a transplant involves for the recipient and the donor, and what each costs. The wider masterclass, covering surgical advances, congenital heart disease and prevention, is summarised in the complete guide to advances in heart surgery and cardiac care.

When heart failure stops responding to medicines

Heart failure means the heart can no longer pump enough blood to meet the body's needs. Dr. Kaul emphasised that there are many medicines for heart failure, and that a patient who presents with it is first treated with them. For heart failure with reduced ejection fraction (a weakened main pumping chamber that ejects too little of its blood with each beat), current guidelines build that treatment on four classes of drug, increased to the doses the patient tolerates: an angiotensin receptor-neprilysin inhibitor (or an ACE inhibitor), a beta-blocker, a mineralocorticoid receptor antagonist, and an SGLT2 inhibitor. The four drug classes are covered in detail in Dr. Rajpal Singh's article on the four pillars of heart failure therapy. Many patients stabilise, and some recover a good part of their heart function.

The patients Dr. Kaul focused on are those for whom this is no longer enough. Once even the medicines stop working, he said, something more has to be done. In these patients the heart is so weak that no operation to repair it is possible, and there are only two treatments: a heart transplant or an artificial heart. In clinical terms, this is advanced (end-stage) heart failure: persistent severe symptoms, repeated hospital admissions and worsening organ function despite optimal medical therapy.

Heart transplant: still the best treatment for heart failure

For the patient who is dying and on whom no medicine is working, Dr. Kaul was clear that a transplant is still the best treatment for heart failure. He illustrated the point with one of his first transplant patients, operated on around 12 years before the session. That man is still doing well, follows his normal routine and has become an athlete.

Where the donor heart comes from

A question from the audience asked what happens to the donor. Dr. Kaul's answer was direct: the donor is already dead, so nothing happens to the donor. A heart transplant is not a live donation. Most donor hearts come from people declared brain dead, whose circulation is maintained on a ventilator until the organs are retrieved with the consent of the family.

Matching the heart to the recipient

Because donor hearts are scarce, they are allocated with care. Asked during the session about an unconventional form of transplant, Dr. Kaul said such a transplant is possible, but few doctors would be willing. The heart is a very precious organ, he said, and the waiting list is huge: there is no reason to transplant a heart into a patient whose outcome is uncertain when a long list of others is waiting. The heart always goes to the best-matching person, so that it is not wasted on a recipient who then rejects it because the match was poor. Matching is based chiefly on blood group compatibility, body size and the recipient's antibody profile.

The wait for a donor heart

The central problem with transplantation is supply. Dr. Kaul described a long waiting list, with many patients waiting for a heart. A patient listed for transplant may wait 6 months, 8 months or a year before a suitable heart becomes available. Some patients deteriorate before that happens, and it is for them that the artificial heart exists.

Lifelong anti-rejection treatment

Asked whether a transplant recipient must stay on medicines to suppress rejection, Dr. Kaul said yes, and that this applies to any transplant: liver, lung or heart. Immunosuppressive treatment continues for life, because the immune system otherwise attacks the donor organ. He added that the cost of these medicines in India is very low compared with the rest of the world, though he could not speak to their cost in other countries.

How an artificial heart (LVAD) works

Dr. Kaul's explanation of the artificial heart starts with the natural one. The heart, he said, is basically just a pump. Blood leaves the heart and travels around the body, delivering nutrition and collecting waste products. It then passes through the lungs, where it is purified (carbon dioxide is given off and oxygen taken up), returns to the heart, and is pushed out to the whole body again.

If a pump is that simple, why did an artificial one take so long? Because blood placed in an ordinary pump and pushed along clots and is damaged. The artificial heart is therefore a special pump, and Dr. Kaul noted that it took almost 50 years to perfect.

The current generation of devices rests on magnetic levitation, the technology he compared with the high-speed trains in Japan that run just above the rails without touching them. In the pump, the spinning rotor is suspended by magnetic fields, with no mechanical bearings and wide gaps for blood to pass through. That design reduces the mechanical stress on blood cells and the risk of clot forming inside the pump.

The pump is attached to the tip of the left ventricle, the heart's main pumping chamber, and returns blood to the aorta. A cable, called a driveline, passes out through the skin of the abdomen and connects the pump to an external controller and batteries, which the patient carries in a bag. In Dr. Kaul's slide of an LVAD patient, the bag and its cable were visible.

How long an artificial heart lasts as a bridge to transplant

Dr. Kaul presented the LVAD primarily as a bridge to transplant: a way to keep a patient alive and well until a donor heart becomes available. Current devices have no fixed design limit; in the MOMENTUM 3 trial, about 58% of patients with the latest device were alive at five years, and some patients live with one for a decade or more.

His case was a patient who had travelled from the Middle East for a transplant. No heart became available; he waited 8 months and then began to deteriorate. Offered an artificial heart, he accepted, and he has continued to return to Dr. Kaul for follow-up years later, doing very well.

Because the long-term treatment is always a heart transplant, Dr. Kaul's guidance is that the conversion should happen as early as possible. Even so, he has seen patients live 10, 12 and even 15 years on the device without undergoing a transplant.

Some patients are not candidates for transplant at all, because of age or other illness. For them, an LVAD can be implanted as permanent treatment, known as destination therapy. The criteria and referral pathway for both uses are set out in detail in Dr. Biswarup Purkayastha's article on the LVAD as a bridge to transplant.

LVAD complications: bleeding, infection and stroke

Dr. Kaul identified three main complications of living with an artificial heart:

1. Bleeding. The patient must take blood thinners to keep the pump from clotting, and this carries a risk of bleeding.
2. Infection. The device and its cable create a route for infection.
3. The need for a transplant. When the device is used as a bridge, patients still need to proceed to a transplant.

Infection most often starts at the point where the driveline exits the skin, which is why patients and families are trained in sterile dressing care before discharge. Stroke and pump malfunction are the other recognised serious complications, and they are the reason LVAD patients remain under close specialist follow-up for as long as the device is in place.

Artificial heart vs heart transplant: the comparison

Artificial heart cost

One artificial heart costs around 1.5 crore rupees in India, a figure Dr. Kaul described as a major cost. Transplant itself is followed by lifelong anti-rejection medicines, which he described as far cheaper in India than in the rest of the world. Indicative costs for cardiac procedures are listed on the heart surgery cost page.

For families from Africa considering treatment, the comparison of the two options therefore runs on time as well as money: the transplant offers the best long-term outcome but depends on a donor heart becoming available, while the artificial heart does not depend on a donor but carries a substantial cost. The rules that govern donor heart allocation for international patients are covered in Dr. Purkayastha's guide to heart transplant for foreign nationals.

Heart and lung transplant for Eisenmenger syndrome

One further transplant featured in the session. In Eisenmenger syndrome, where an untreated heart defect has irreversibly damaged the lungs, the definitive treatment is a combined heart and lung transplant, which Dr. Kaul described as very difficult, with a success rate of around 40 to 50%. The condition and its prevention are discussed in the complete guide.

Doctors' questions on LVAD complications, how the artificial heart works, donors and anti-rejection treatment, with Dr. Kaul's answers, are on the Live Discussion page. More on his practice is on Dr. Ajay Kaul's profile.