It was a simple bee sting that gave Susie Murray the first inkling that something might be seriously wrong. Aged 23 at the time, she suffered a mild allergic reaction and took an antihistamine, but she still felt faint. Her husband Alan drove her to A&E, where she was given an injection of adrenaline – a routine treatment. It almost killed her.
'I remember the doctor putting the needle into my arm, then sitting up and telling her that I felt funny', Susie recalls.
'And then I don't remember anything. I went into cardiac arrest.'
Defibrillator paddles were used to shock her heart back to life. Susie recovered, but doctors could offer no explanation for her reaction.
She would later learn it was a warning sign of an inherited heart condition that has since claimed the lives of several members of her family – a condition for which adrenaline is a trigger. Susie, now 50, a retired senior administrator for an insurance company, who lives in Gunnislake, Cornwall, with Alan, 55, a retired funeral director, suffers from sudden arrhythmic death syndrome, commonly known as SADS.
The condition, which kills ten Britons a day, has robbed her of a sister and a daughter. Her son Alex, 15, has a one in two chance of developing it in later life. As a result she has become a tireless campaigner to raise awareness of SADS, and has raised money to install a portable defibrillator in Alex's school.
SADS is an umbrella terms for several genetic cardiac conditions that cause instability in the heart's electrical system which can force the muscle into overdrive.
'The heart beats so quickly that the blood supply to the brain is switched off and it usually means death within seconds,' explains Dr Sanjay Sharma, professor of cardiology at St George's Healthcare NHS Trust in South West London.
One in 2,000 people carries the genes, and carriers have a 50 per cent chance of passing it on to their children. Those with the gene have a two per cent chance of succumbing to an attack each year. Warning signs include dizziness, palpitations and blackouts but often there are no prior symptoms.
It was not until 1999, and the death of her sister Dawn at the age of 34, that Susie was diagnosed with SADS. The sisters had separately been seeking explanations for the same problems for some time – breathlessness, tiredness, lack of energy. When Dawn suffered a fatal heart attack, the coroner ruled it was SADS, and Susie and her daughter Nadine were advised to have an electrocardiogram.
An irregular heartbeat was detected in Susie, but Nadine's heart appeared normal. Then, three years later, further tragedy struck.
'Nadine was 21 and studying for an equine HND, says Susie.
'She was under a lot of stress. One day I got a call to say she hadn't turned up for an exam. It was a dreadful moment, but I just knew – I had always had the odd idea I would lose someone else, and it was my beautiful daughter.'
Dr Sharma explains that while Nadine's ECG suggested no abnormalities, stress-testing may have shown otherwise.
'If the patient is put on a treadmill it can unmask the telltale delay in the heartbeat that points to SADS,' he says.
SADS sufferers are advised to avoid stress and high-workload sports, as well as certain antibiotics, antidepressants and antihistamines, and are prescribed beta-blockers to keep their heart rate low.
And Susie and son Alex have both been fitted with an Implantable Cardioverter Defibrillator (ICD).
'ICDs are like pacemakers,' explains Amanda Varnava, a consultant cardiologist at Imperial College Hospital.
'It is fitted under the skin on the chest. It continuously monitors and can regulate the heartbeat, but also gives a brief electric shock if it detects an abnormal rhythm.
'Susie's ICD saved her life in 2008.
'One morning I began to feel incredibly tired,' she recalls.
'Looking down I saw a glow under the skin in my chest, and then bang – the ICD went off. I woke up on the floor, realised what had happened, and immediately called an ambulance.
'The machine went off again on the way into hospital – without it I would have been dead for sure.
Ann Jolly, founder of SADS UK – the Ashley Jolly SAD Trust, which aims to prevent premature deaths due to SADS – say an awareness of the symptoms is essential.
'These conditions can be diagnosed and treated appropriately if they're caught early enough.'
Susie, meanwhile, has vowed to keep her son safe from the condition to which she lost a sister and daughter.
'Nadine would have been 30 this year, and might have had children of her own,' she says.
'Losing her has left a hug gap in our lives. I'm determined not to lose my son.
