Nina is laughing and playing happily, just like any other four-year-old. It seems like the most natural thing in the world, but for her parents it’s “like a miracle”. “Now Nina‘s going to nursery school,” beam her parents Claudia and Michael L. from Bocholt (Germany). The fact that Nina has overcome so many setbacks is down to a special device designed to support heart function in children.
“During the fourth week of her life, a U3 screening test revealed heart murmurs,” recalls Claudia L. Further testing showed that Nina had been born with a serious heart defect. “Both cardiac valves involved in pumping blood into the ventricles that serve the body’s systemic circulation, namely the mitral and the aortic valve, were affected, and so were the coronary arteries or aortae,” says Dr Alexander Horke, head of the Surgery of Congenital Heart Disease department at Hannover Medical School (MHH). “Before the age of one, she required three operations to repair the coronary arteries and the valve region. And a pacemaker had to be fitted.”
However, it soon became evident that constriction in the region of the aortic valves had returned. “Pulmonary hypertension had also developed, with markedly compromised cardiac function,” paediatric heart surgeon Dr Horke explains. “In principle, this may be a good enough reason for a heart transplant – or even a combined heart and lung procedure,” adds Professor Axel Haverich, director of the Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG).
However, the doctors nurtured the hope that Nina’s heart could recover if it had a properly working valve, thus preventing the need for a transplant. So they suggested to Nina’s parents that she be implanted with what is known as a ‘Hannover valve’. This tissue-engineered, decellularized cardiac valve developed by Professor Haverich and his team has been used in more than 150 young patients and proven effective. “Because of Nina’s poor heart function, we had to use extracorporeal membrane oxygenation (ECMO) during the first six days after surgery – this is a mechanical circulatory-support system,” remembers intensive-care specialist Dr Harald Köditz, a senior physician at the Department of Paediatric Cardiology and Paediatric Intensive Care Medicine. But Nina recovered only very slowly after the procedure in early March 2016. Cardiac catheterization revealed that, although the new heart valve was working well, the performance of the heart itself remained impaired.
“After extensive discussion with her parents, at the end of April 2016 we decided to put Nina on the list for a heart transplant,” reports Dr Horke. As her heart was so weak by then that her condition was critical, the physicians opted to implant a special ‘ventricular assist device’ for children. “We wanted to do this in order to bridge the wait.” Dr Murat Avsar, of the Surgery of Congenital Heart Defects team within the HTTG, outlines how this device – called a Berlin Heart – works: “In ventricular assist devices for adults, a minute pump is implanted right next to the heart, and only the control unit and power supply are worn outside the body on a belt. By contrast, in this system – the EXCOR Pediatric device – the blood pump is also external (paracorporeal).” The Berlin Heart ‘artificial heart’ system is connected to the heart and blood vessels using tubes called cannula. It consists of a blood chamber and an air chamber separated by membranes. Dr Avsar, who implanted the ventricular assist device together with Dr Horke, explains how it works: “The movement of air in and out of the air chamber is controlled by a driving unit. It moves the membranes, which draw blood into the blood chamber and push it back into the child’s body (specifically, the large blood vessels). Like the heart, the device’s blood pumps have valves which ensure that the blood only flows in one direction.”
An uncertain period of waiting began; when would a heart be available for Nina? “Thanks to the assistance of this artificial heart, Nina was stable,” Dr Horke recalls, “although, after half a year, we did have to remove protein-rich fluid from around the heart twice. Nina also had to weather a serious infection.” The phone call that finally brought relief came on 5 November 2016. “A donor heart for Nina had been found; size-wise it wasn’t ideal, but we still felt it was acceptable,” says Professor Gregor Warnecke, in charge of profiling for organ transplantation at the HTTG. “Donors and recipients need to be matched in terms of blood group and weight. Suitable donor organs are not easy to find, and that applies not only to adults, but to children too – which explains the long waiting period of more than six months.” On the very same day, Professor Warnecke and Dr Horke successfully transplanted Nina with a heart provided from another European country. It had already had a long journey in a special organ-perfusion machine, the Organ Care System.
“Over the following six weeks, Nina made a steady recovery; she was able to leave our intensive-care unit before Christmas and be transferred to general ward 68,” says Dr Köditz. On 10 January 2017, she was discharged home – after eight months in MHH’s Department of Paediatrics! “It’s great to see Nina doing so well again; it’s a wonderful success story,” stresses Professor Philipp Beerbaum, director of the Department of Paediatric Cardiology and Paediatric Intensive Care Medicine. “And it shows the importance of interdisciplinary collaboration and the specialist expertise we make available at our centre for children and adults with congenital heart disease.”
Cardiac surgeon Professor Haverich points out that the ordeal for Nina and her family would have been shorter if more people had a more positive attitude towards organ donation. “Regrettably, the reverse is true: the number of organ transplants carried out in Germany is falling.” He appeals to the public to consider how they would feel if they or a relative were affected: “Would the prospect of death on the waiting list still not bother you if it was a loved one, or even yourself?”
MHH is Germany’s largest transplantation centre. In 2016, its medics transplanted 410 solid organs – a statistic including 21 heart transplants, five of them involving children. So far this year there have been 19 heart transplants, including three in children.
Further information is available from Dr Alexander Horke, Tel. ++49 (0)511 532 9829, .