For over 50 years, heart transplantation has been regarded as the “gold standard” in treatment of cardiomyopathy and end-stage heart failure.
But Cape Town-based cardiothoracic surgeon Dr Willie Koen told the congress of the South African Transplant Society in Gordon’s Bay last weekend that this can no longer be considered the case if transplantation remains isolated from technology that can assist the heart to pump.
And Koen said that mechanical assist devices (MAD) have already been developed which can be fully implanted adjacent to the heart, with the internal batteries re-charged wirelessly from outside the body.
Koen, who runs a busy heart transplant programme at Christiaan Barnard Memorial Hospital, has gained renown in recent years for his work in implanting MADs such as left ventricular assist devices (LVAD) in patients experiencing end stage heart failure and who are waiting for a donor heart to become available.
MADs are widely used globally as a “bridge-to-transplantation, but Koen points out that in the United States, many patients who receive an LVAD take themselves off the heart transplant waiting list because they are happy with the treatment. The big downside until now, however, has been the large battery packs which patients must carry around their bodies throughout their lives.
In a wide-ranging exploration of the technology available for treating failing hearts, he said these developments were underpinned by the worldwide societal shortage of donor hearts.
“Our problem in SA is that we have about half-a-million people with end stage cardiac failure at any time, with 5,000 people who are eligible at any one time for a heart transplant, and we do less than 50 heart transplants a year. So, we don’t even scratch the surface of treating the problem.
“The total implantability of a small heart pump with no batteries will be the end of cardiac transplantation as we know it. Total implantability will be a game changer. This is not all science fiction. The first human implant with a total wireless battery system was done in April this year,” he said.
It’s all about nanotechnology which, in turn, is all about graphene, a super-strong but very thin, light and malleable material based on graphite and which was discovered in 2004. Graphene, said Koen, will be the basis for much smaller technologies implanted in the human body in the future.
In the case of heart failure patients, once the MAD has been implanted, the patient wears a vest with the battery charger and a controller on the wrist which indicates how full the battery is. But once the battery is fully charged, the patient can remove the vest for six hours.
Koen said the only barrier to having these technologies available in South Africa is cost. As an example, he cited the impella, a highly effective MAD for patients with severe heart failure. However, it can only be used continuously from between a few hours to up to three weeks. Koen said the R300,000 cost of the device in South Africa, depending on the rand-euro exchange rate, meant it was not cost effective treatment for only three weeks “in our setting”.
– RAY HARTLE