- Title: US: New Yorker marches to beat of artificial heart research
- Date: 14th December 2012
- Summary: PRAGUE, CZECH REPUBLIC (AUGUST 29, 2012) (REUTERS FILE) WIDE OF NEWS CONFERENCE WITH PATIENT JAKUB HALIK AND DOCTOR JAN PIRK (SOUNDBITE) (Czech) PATIENT JAKUB HALIK SAYING: "I don't even realise it, because the functions of the body are the same, only my heart is not beating and I have no pulse anymore. This is the only difference but otherwise I am functioning like a hea
- Embargoed: 29th December 2012 12:00
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- Topics: Health
- Reuters ID: LVA2YDZOI7ILRNL0PTRGFNOSEOU
- Story Text: For 28-year-old Daquain (PRON: Der-kwarn) Jenkins of Monticello, New York, the repetitive beating sound that accompanies him where he goes is not annoying, but a vivid reminder that he is alive and that his implanted artificial heart is working. To him the perennial loud thumping beat is the sound of life.
Jenkins, a father of three, was diagnosed with congestive heart failure at the age of 25 and received a heart transplant in April 2011 after all other options failed. His body rejected the transplanted heart in August this year and as both sides of the organ began failing rapidly a temporary Total Artificial Heart (TAH), developed by US firm SynCardia, was flown in and surgically transplanted into him. A TAH replaces the two lower chambers of the heart, known as ventricles.
According to his doctors, the portable artificial heart will enable him to live at home until another donor heart becomes available. It can last for two hours on battery power when not plugged in to an outlet or car charger. But Jenkins always keeps additional charged batteries at hand and is not worried about his artificial heart running out of power.
Jenkins know his heart intimately.
"Air travels through the lines.....and these tubes that are hanging out are connected to the artificial heart that's in here using air and uses air to pump the valves, the artificial valves that are in here that pumps the blood throughout me and keeps me alive. My lifeline," he said.
Jenkins says he's become accustomed to monitoring the various aspects of his artificial heart - from beats per minute (BPM) to fill volume (FV) and cardiac output (CO). The system that's enabling him to function consists of two parts - the Freedom Driver System, a 13-pound device enclosed in a backpack which powers the heart, and the artificial heart itself.
Jenkins, whose father died of heart failure aged 28, hopes to continue his studies to become a web designer and to be able to walk his kids to the school bus stop, a simple task that he says had become impossible because of his previous failing heart.
Dr. Anelechi Anyanwu, Jenkins' Cardiothoracic Surgeon, explains that the artificial heart serves as a bridge for patients with failed hearts as they await transplantation. He pointed out the strengths of the system -- one being that it gives patients mobility but he also warned of the failings, such as the fact that it cannot yet be customised to specific patient needs.
"This device itself is made of special kinds of plastic and it has mechanical heart valves within it to keep blood flowing the same direction and it's essentially the same pump that's put in everybody, and the technology itself goes back to the 1980s actually, the fundamentals of the technology, so in a way it's just a crude mechanical pump that just moves blood in one direction and that's where we are now, but there are several developments going on, for example to make smaller pumps, to have better power supplies and ultimately to have a pump that the whole mechanism of the pump is within the body," he said.
In the distant future, Anyanwu hopes that the artificial heart is not just seen as a temporary fix but as a viable long-term option for those with serious heart defects.
In October 37-year old Czech fireman Jakub Halik died after surviving for more than six months without a heart, having been fitted with a similar device. His heart was removed and replaced by two modified Heartmate 2 pumps, manufactured by US company Thoratec Corp, during an eight hour operation performed by leading Czech cardiologist Jan Pirk in April. Halik had suffered from a highly aggressive tumour in his heart which had to be removed. A standard heart transplant was not an option because anti-rejection drugs administered afterwards cannot be taken by cancer patients.
Use of a single pump is more common to support the heart's left side, helping pump blood through the body. A total artificial heart containing two pumps leaves the patient without a pulse.
At a press conference six weeks before his death Halik described how he was coping.
"I don't even realise it, because the functions of the body are the same, only my heart is not beating and I have no pulse anymore. This is the only difference but otherwise I am functioning like a healthy man at present," he said.
But despite his patient's death, Professor Pirk says the technology is moving fast.
"I am convinced that new pumps fully able to replace the heart function will be discovered in the future. It's not the case yet, but they can already function to help the left heart chamber work properly. With this pump patients can live and some patient have lived with it for seven years now."
In November the U.S. Food and Drug Administration approved a heart pump made by HeartWare International. The FDA said the life-saving benefits of the HeartWare left ventricular assist device (LVAD) in the intended population of patients with end-stage heart failure outweighed risks observed during the clinical trial, such as infection and stroke.
Steven Tsui (PRON: Soo-Eey), one of the UK's foremost cardiac surgeons, who implanted a SynCardia TAH into Briton Matthew Green in August 2011, says the HeartWare device is lighter and more compact than its predecessors.
"It weighs over one kilogram. It's a very big device, whereas the latest left ventricular assist device that is available is something like this and as you can see this is a fraction of the size of the first generation device. It is much lighter. The inflow and the outflow are now integrated into the pump and the drive line cable is also much more flexible and much smaller," said Tsui.
According to Tsui, the HeartWare pump is likely to be very popular.
"I anticipate that this will be the next most successful LVAD in the world. The reason why this is so much better than older devices is because it is much more effective and efficient in power consumption so the same battery would last a lot longer for the patient. It is completely silent in operation and the small driveline means that the exit site through the skin will be much easier for the patient to manag and therefore may reduce the complication rate associated with the use of these devices," he said.
The first artificial heart to be successfully implanted in a human was the Jarvik-7, designed by Robert Jarvik and implemented in 1982. The first two patients to receive these hearts, Barney Clark and William Schroeder, survived 112 and 620 days beyond their surgeries, respectively. After a variety of modifications the Jarvik-7 evolved into the SynCardia Total Artificial Heart.
An artificial heart is distinct from a ventricular assist device designed to support a failing heart. It is also distinct from a cardiopulmonary bypass machine, which is an external device used to provide the functions of both the heart and lungs and are only used for a few hours at a time, most commonly during cardiac surgery.
A synthetic replacement for the heart remains one of the long-sought holy grails of modern medicine. The obvious benefit of a functional artificial heart would be to lower the need for heart transplants, because the demand for organs always greatly exceeds supply.
According to SynCardia, the longest a patient has been supported with the Total Artificial Heart is 1,374 days - almost four years - before the patient received a successful heart transplant. - Copyright Holder: FILE REUTERS (CAN SELL)
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