The cardiac arrest that caused Muamba, 23, to collapse during Saturday’s FA Cup tie against Tottenham is thought to have been caused by arrhythmia, or disorder of the heart rhythm. This could have been induced by a number of underlying heart conditions, most stemming from an abnormality of the heart muscle.
“One of them is hypertrophic cardiomyopathy [HCM],” the cardiologist said. “This is a condition which can have a genetic basis, which may run in families or as an isolated case. It’s where the left ventricle has totally disorganised and thickened. Severe cases can present as sudden death during exercise. It’s an unusual but serious rhythm disorder. The heart shivers and shakes and stops beating properly.”
Another potential cause is right ventricle dysplasia, a condition where the heart is infiltrated by abnormal fatty tissue. This is more difficult to diagnose, sometimes requiring an MRI scan to detect.
Other heart conditions that may induce sudden collapse are Brugada Syndrome and Long QT Syndrome, where the electrical flux in the heart muscle can become abnormal.
What is not known is why it is particularly fatal to the young, or why certain athletes can compete for years at the highest level without displaying any symptoms. Junior players aged 16-17 undergo ECG and echocardiogram heart checks funded by the FA, but the cardiologist said that some conditions could develop later in life, and at present there is no mandatory requirement for clubs to test their players for underlying heart conditions.
“There is some evidence that these conditions may not be apparent when a player is 17 but may become apparent later,” the cardiologist said. “If you have a normal echo at 17 or 18, it doesn’t mean you will in three years’ time, if you have the wrong gene.”
Once a patient goes into cardiac arrest, swift action is required, he added. “You need to defibrillate within a couple of minutes to allow the heart to restart. When they collapse, if you don’t start cardiac massage – if you can’t shock the heart, the brain gets starved of oxygen. You may save the heart, but you haven’t saved the brain. That’s the worst situation.”
This it Video Fabrice Muamba Collapses 17th March 2012 Bolton vs Tottenham :