Chance encounters: How Karen Sliwa is putting African cardiology on the map

29 September 2016 | Story by Newsroom
Karen Sliwa. Photo: Michael Hammond.
Karen Sliwa. Photo: Michael Hammond.

Professor Karen Sliwa's career has been characterised by chance and a lack of convention, and she has now broken convention again: the first female and the first person from Africa to be elected as president of the World Heart Federation.

When Karen Sliwa was a teenager, her teachers called a special meeting to discuss her 'unruly and rebellious' behaviour. "I often skipped classes and simply could not be bothered with the rules and conventions. I wanted to do my own thing," Sliwa recalls. "Luckily for me, I had very good marks, so they let me be." Little did they know that this free spirit would develop into one of the world's leaders in cardiology and become the first female, and the first based at an institution in Africa, to be elected president of the World Heart Federation (WHF).

“I am honoured to have been elected in this position,” she says, “as the federation works with more than 200 member organisations around the world and reports to the World Health Organisation.

“I aim to create a highly visible and somewhat 'noisy' WHF, which will serve in an advisory capacity to ministries of health in various countries to achieve a common goal of improving cardiovascular health – from pre-conception, to childhood through to older age. A counterforce is needed against the promotion of sugar-enriched beverages and the aggressive marketing of energy-dense, nutrient-poor food, particularly in middle- to low-income countries.”

Sliwa, director of the Hatter Institute for Cardiovascular Research in Africa at UCT, has published over 180 articles to date and has received numerous international awards in recognition of her work, but her specialism in cardiology was the result of a chance decision.

“My daughter's nanny, who had recently given birth to a baby, was swollen, short of breath and very tired. I took her to the Chris Hani Baragwanath Hospital in Johannesburg, where I worked as a house officer.”

The nanny was diagnosed with peripartum cardiomyopathy, a rare type of heart failure that occurs during the last month of pregnancy, or within five months after the baby is born. “I was dumbfounded, as I had never heard of this condition. Everyone seemed to know about it, but no-one knew what the cause was or how to treat it. Why was no-one writing about it?”

Sliwa started to research the condition and soon discovered that the symptoms were commonly misread by medical staff. "Most mothers are tired when they have new babies and get little sleep. The problem, though, is that the mother's health keeps deteriorating and when they die, there is no connection made between giving birth and their death,” she says. “I was curious to find out what the mechanism is of the disease and how it can be treated."

Sterling teamwork over a decade with a scientist from Hannover, Germany, Professor Denise Hilfiker-Kleiner, who noticed the same condition in mice after they produced offspring, led to the discovery that the heart failure is linked to an abnormal breastfeeding hormone which activates an abnormal cardiac signalling pathway.

“The treatment turned out to be very simple and affordable: we give the patient a cheap, generic medication that stops breastmilk production, and the baby gets formula milk,” says Sliwa. “However, we are awaiting confirmation of those data by larger studies.”

Today, Sliwa is regarded as a world leader in peripartum cardiomyopathy research. She has been extensively involved in creating awareness of the disease, including starting a worldwide registry.

Research in the heart of Africa

Sliwa expanded her heart research in South Africa by establishing the 'Heart of Soweto Study' which investigates the prevalence, presentation and management of cardiac disease of more than 8 000 patients at the Chris Hani Baragwanath in Soweto, and highlighted the high prevalence of hypertension, obesity and cardiac disease in women of childbearing age.

She has recently expanded her population studies (under the umbrella of the 'Heart of Africa Studies') to other African countries, including Mozambique, Nigeria, Tanzania, Kenya and Sudan.

One of Sliwa's proudest achievements is her contribution to help people in the Western world recognise the importance of research and reporting on health problems in Africa, with a specific focus on heart disease and women. "In the past, many journals were just not interested in African studies, and, before the 1990s, many cardiology trials simply did not include women.”

A pioneering move

Rather like the decision to specialise in cardiology, it was chance that brought this pioneer of cardiovascular research to the continent – and even to go into medicine in the first place.

Born in Germany and spending most of her childhood in Japan (where her father worked as a biologist), Sliwa had no idea what to study after school. “So I applied for law, social sciences and medicine,” she says, “and was accepted first by the Charité Medical School in Berlin. I did not particularly enjoy medicine, but worked hard because I believe that you should deliver your very best in everything you take on.”

Her move and subsequent emigration to South Africa as a junior doctor in 1992 was also sheer coincidence. The adventurous Sliwa and her spinal surgeon husband Dr Ulrich Hähnle had applied for jobs in different countries; and the first offers that came in and were in the same town, happened to come from Johannesburg. Two weeks later, they also received offers from Australia and four weeks later from Scotland.

Sliwa's sterling career suggests this move was a lucky one both for her and for cardiovascular research. The impact of her research continues to be felt globally: she was recently asked to write an article of her choice and length for The Lancet - a very rare open invitation – and was subsequently invited to give the prestigious Academy of Sciences-Lancet International Health Lecture in London in October this year on the same day her article is published.

"I don't think I have ever felt so honoured!” says Sliwa. Those who have kept an eye on her career, however, cannot doubt that there will be many more such honours to come.

Story Birgit Ottermann. Photo Michael Hammond.

World Heart Day
On Thursday 29 September, the world celebrates 'World Heart Day', an opportunity for people across the globe to take part in the world's biggest intervention against cardiovascular disease (CVD).

“For the first time, the World Heart Federation, The South African Heart and Stroke Foundation and the South African Heart Association have paired up to celebrate World Heart Day in South Africa,” says Karen Sliwa, UCT professor in cardiology and president-elect of the World Heart Federation.

“Our message is that, by making healthy lifestyle choices, you can do much to help prevent heart disease.”
  • Focus on 'knowing your numbers': have yourself tested for hypertension and high-density lipid (HDL) and low-density lipid (LDL) cholesterol.
  • Live a healthy lifestyle: make smart food choices (reduce salt and sugar intake and increase fruit and vegetable consumption), engage in physical activity (30 minutes a day for five days a week), avoid smoking, and reduce stress and emotional distress.
  • Inform yourself of genetic predisposition for CVD in your family and how middle and older adult years can be risk factors for CVD onset.
  • If diagnosed with CVD, stay on treatment, and talk to the doctor, nurse and allied health practitioner.
  • Help empower others to improve their overall health and prevent CVD onset.
  • Spread the news that shortness of breath in pregnancy or after giving birth can be a sign of a heart problem and needs to be checked up.
Sliwa acknowledges the government's active involvement in improving public health. In February 2016, South Africa became the first African country to announce plans to introduce a new tax on sugar-sweetened drinks. This 'sugar tax' will come into force from April 2017. And, in 2013, the government introduced legislation in line with targets set to reduce salt intake to less than 5g a day per person by 2020. High intakes of sugar and salt have both been linked to an increased risk of heart disease.
UCT Research and Innovation

Creative Commons License This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Please view the republishing articles page for more information.