Have you inherited a deadly heart gene without knowing it?
FROM the moment her boyfriend Rob proposed, Caroline Stroud dreamed about her bi g day and starting a family with the man she loved. But a year after she said yes, Caroline was questioning whether she should call it all off. It wasn’t that she no longer loved her fiance — rather that, aged just 30, she had been diagnosed with an inherited heart condition.
Although she had no symptoms and was fit and well, the condition meant her heart could stop suddenly at any time — and any children she had might also have the lifethreatening condition.
Caroline discovered she had the heart problem only because her otherwise healthy father had suddenly become ill.
Many others are living under the same threat, they just don’t realise it. About half a million people have a faulty gene which puts them at risk of a heart defect that could lead to a sudden premature death, says the British Heart Foundation.
‘It is an estimate, but it may be even more common than that,’ says Professor Peter Weissberg, a cardiologist and medical director of the charity.
‘There are dozens of types of these conditions but all are potentially deadly because they put the patient at increased risk of having a chaotic heart rhythm and a cardiac arrest, where the heart stops pumping.’
The most common is hypertrophic myopathy, which causes the heart to thicken and affects 100,000 Britons. Others include long QT syndrome, which affects the heart’s electrical activity.
Each year about 600 healthy people under 35 die suddenly, often as a result of an undiagnosed inherited heart disorder.
Yet these conditions can cause problems at any age. The problem is that there are rarely tell-tale symptoms.
‘The biggest clue to whether someone is at risk is to examine their family history and see if any relatives suddenly died under 35,’ says Professor Weissberg, adding that by the time people reach their 50s ‘coronary heart disease is the bigger threat’.
‘Sometimes you hear of people who have had two or three relatives who drowned — we now know that cold water can trigger a misrhythm of the heart, leading to sudden cardiac arrest with these inherited conditions.’
While there was no history of sudden death in Caroline’s family, in November 2008 her father Barry, 60, became inexplicably breathless and generally unwell.
CAROLINE persuaded him to go to the doctor. At the surgery he became grey and breathless again and tests showed his heart was beating so erratically that he was at risk of cardiac arrest; he was rushed to hospital and defibrillated to get his heart working properly again. Without this, he could have died.
Tests revealed that the problem stemmed from an inherited heart condition, arrhythmogenic right ventricular cardiomyopathy (ARVC) — essentially a fault with the proteins that hold the heart muscle cells together.
‘These act like a molecular glue — if there is a fault with this, the heart can enlarge,’ explains Professor Hugh Watkins, a consultant cardiologist based at Oxford University.
Scans showed that Barry’s heart had started to enlarge and, as there Half a million Britons are unaware they’re at risk — until a relative dies was a good chance of him having a cardiac arrest, he needed to have a mini-defibrillator implanted in his body to jolt his heart into beating properly again if this happened.
The news was a shock. Caroline says her father ‘always seemed healthy. He was slim and seemed strong physically’.
Barry got help just in time. But his diagnosis threw up bigger issues for his children. Caroline and her brother Chris, 33, and sister Jo, 38, were offered screening to see if they had the faulty genes. (Normally, genetic testing is also offered automatically to the relatives of someone who dies suddenly under 35.)
This involved a straightforward blood test, but having it wasn’t a straightforward decision.
‘Part of me didn’t want to know,’ recalls Caroline, now 35. Not least because for her father’s condition, until someone reaches the point of needing an implant, as he had, there is no treatment.
Genetic testing has made a big difference, says Professor Weissberg. ‘Before we had the tests five or so years ago, we could only look at a family history and say “It looks as if you have the faulty genes” when maybe the person didn’t.’ Not everyone who tests positive will necessarily be at risk of cardiac arrest or even have heart problems.
‘What we call the event rate (the number of cardiac arrests or actual problems caused) is low, so you may have this genetic defect but have a normal lifespan,’ says Dr Sanjay Sharma, consultant cardiologist to the charity Cardiac Risk in the Young (CRY).
YET having the test means treatment can be given or lifestyle advice offered to help prevent the condition becoming life-threatening.
‘Something like long QT can be simply treated with medication to regulate the heart rhythm,’ says Professor Watkins.
Another option i s having a defibrillator implant. The difficulty for those facing gene tests is that a positive result — even if you have no symptoms — can bar you from certain careers, such as in the Armed Forces. It can also cause a lot of anxiety.
‘Some people — especially young men — decide they would rather not know but tend to change their minds when they have f amilies of their own,’ says Professor Watkins.
Before they had the tests, Caroline and her siblings (their mother died 20 years ago from cervical cancer) received counselling.
‘If we had the faulty genes, there was no way of knowing when or if the condition would start to cause changes to the heart,’ says Caroline. ‘There’s no treatment even if we tested positive.’
A defibrillator would be given only if the heart was showing signs of damage. ‘But we were all agreed we had to find out.’
Caroline had the blood test early in 2010. The results showed she has both the faulty genes involved in her father’s condition. Her brother and sister had only one, so their hearts wouldn’t be affected.
‘No amount of counselling prepares you for getting a positive result,’ says Caroline. ‘I tried to hide my distress from Dad because I didn’t want to make him feel guilty — but I was very, very upset.
‘It changed the way I felt about getting married and having a family. I didn’t want to lumber Rob with all this and I was concerned about handing it on to our children.’ She and Rob were due to marry that year, but she told him she would understand if he wanted to call it off. ‘luckily, he told me not to be so silly.’
Caroline now has a heart check-up every six months. She still goes to the gym but exercises more gently. ‘I’ve bought a heart monitor and my doctor has said I mustn’t let my heart go over 150 beats per minute. A hard workout used to be my favourite way to relax and I miss it.’
The advice to stick to light exercise is because a third of all cardiac arrests in people with inherited conditions occur during or just after intensive physical activity.
When Caroline became pregnant last year, she was concerned about the birth ‘but they kept a close eye on my heart rate and I was fine’.
Her daughter Zara is now four weeks old and Caroline and Rob face having to get her tested for the defective genes. There is a 50 per cent chance she will have them.
‘It’s difficult because I don’t want her to spend her life worrying about this,’ says Caroline. But she and Rob, who run a financial advice business in Folkestone, Kent, still think they will have her tested.
Meanwhile, Caroline is appearing in television adverts starting this week to highlight the need for more research into heart problems.
‘We need to find the people with faulty genes and treat them early — we may one day develop treatments to halt these conditions,’ says Professor Watkins.