Can anything be done to stop young people in the prime of their lives dropping dead from cardiac arrest, asks Nuala Mackin
The sudden death of 18-year-old Cork hurler, Kevin Quinn, just after the throw-in at a match on Friday, has prompted calls for political action in highlighting potential health issues for sportspeople.
His death is the latest in a series of sudden deaths of high-profile sportsmen, including 22-year-old Tyrone football captain, Cormac McAnallan, and 18-year-old Royal Armagh School team captain, John McCall, who died while on a rugby tour in South Africa
Sudden cardiac death is often thought to be synonymous with the young. However, people of all ages die of cardiac arrest, but it is only when a young person drops dead on a playing field, or dies in their sleep, that conjecture abounds and a logical explanation seems elusive.
Known as Sudden Adult Death Syndrome (SADS) the condition can have a number of underlying causes, including hypertrophic cardiomyopathy, dilated cardiomyopathy, long QT syndrome, arrhythmogenic right ventricular dysplasia and brugada syndrome.
In 2000, the Central Statistics Office reported that 12,660 people died of cardiovascular disease in Ireland. According to the CDC in Atlanta, some 64 per cent of these types of deaths can be attributed to cardiac arrest, almost always due to a sudden and chaotic disturbance of the heart's electrical rhythm.
However, families of those affected by SADS often have to wait a long time before finding out conclusively what happened to their loved ones. Paula and Andrew Larrissey, from Templeogue in Dublin, waited an excruciating four years to receive an inconclusive report from an autopsy which was carried out on their daughter Sharon in 1998.
Just a week after her 19th birthday, Sharon returned from a night out with friends, said goodnight to her parents and went to bed. She suffered a massive heart attack in her sleep and died shortly afterwards.
Paula Larrissey says: "The first thing that ran through my head was that maybe someone had put something in her drink when she was out. It was unbelievable - like a nightmare that we've never woken up from."
It wasn't until consultant cardiologist Dr Joseph Galvin at James Connolly Memorial Hospital in Blanchardstown was able to offer some explanation that the Larrisseys were finally given some closure on what may have happened to their daughter, almost five years after Sharon's death.
Dr Galvin, who specialises in cardiac electrophysiology, spoke about the two varieties of heart attacks. The first are those caused by blockages in the heart's coronary arteries, or plumbing system, which now have an improved prognosis thanks to blood clot-dissolving drugs and balloon angioplasty; and those of the electrical kind which are called cardiac arrests.
These lead to immediate sudden death in about 99 per cent of cases and are known as massive heart attacks or cardiac arrests.
He said: "The most common of the electrical kind are those which result from abnormalities of the coronary arteries and account for 70 to 80 per cent of these cardiac arrests. Less common are those caused by abnormalities in the heart muscles called cardiomyopathy.
"Finally, there are the poorly-understood and less-recognised electrical channel problems which lie within the heart cells such as the sodium, potassium and calcium channels which lie within the membranes of every cell in the heart.
"Screening is used in some countries to keep young people with evidence of cardiomyopathy or cardiac ion channel abnormalities out of competitive sport. This is controversial because of the low positive predictive value of these tests for life- threatening events. Most people who drop dead suddenly were probably born with genetic abnormalities. These can sometimes be detected on an ECG, but the majority of these go undetected. If Sharon's heart looked normal, she probably falls into this category."
At €3,500 each, an automatic external defibrillator (AED) can be used to administer an electric shock to the heart and restore the heartbeat. Currently, there is an AED programme in Croke Park, Dublin Airport, Blanchardstown Shopping Centre and several other venues around the State.