So if someone has an unhealthy heart, they may not necessarily have a symptom from it. People can have blockages of up to 60 or 70 or even 80 per cent in one of the blood vessels to their heart and have no symptoms whatsoever until unfortunately they might have a heart attack. So that’s why we recommend that people over 50 especially have a heart checkup with their GP, but other people with heart problems do have symptoms. And the commonest symptoms are chest pain on exercise, breathlessness on exercise, palpitations, or a combination of the three.

Professor David Celermajer is Scandrett Professor of Cardiology and Head of Cardiology at the University of Sydney.