By Dr. W. Gifford Jones
July 1, 2007
“How could this possibly happen?” is the usual soul-searching response. A young healthy athlete has left home to play in a sporting event. Then in a matter of seconds, collapses and dies before anything can be done to save his or her life. The big question is why these premature deaths occur, and can they be prevented?
Dr. Michael Ackerman is head of the Mayo Clinic's Sudden Death Genomics Laboratory. He agrees that news of these unexpected deaths saddens parents and shocks communities. And when such sudden fatalities strike seemingly invincible star athletes, parents worry it could happen to any child involved in recreational sports. Luckily, he states, these shocking deaths are rare.
Dr. Ackerman reports that there are 300,000 sudden cardiac deaths a year in the United States. Of this number anywhere from 3,000 to 6,000 occur in people under 35 years of age.
Autopsies show that two-thirds of these deaths are due to heart abnormalities. Some young people have a condition called, “Hypertrophic cardiomyopathy”, in which the heart's muscle becomes abnormally thick. It's the most common cause of heart-related sudden death in young people and the one most often seen in athletes. Fortunately, this condition does not usually result in death. But if it's present, doctors often fail to make this diagnosis.
Genetics often plays a major role. Autopsy shows that coronary arteries may be connected to the heart in a bizarre way. The result is that during a strenuous game the arteries are unable to supply sufficient flow of blood to the heart's muscle. This causes the electrical system that normally regulates the heart beat to falter.
We all know what happens in our home when the electricity goes off. For the heart this means that the rhythm becomes chaotic and the heart's muscle suddenly collapses, a condition known as “ventricular fibrillation”.
Other young athletes suffer from what is called a “Long QT syndrome”, another electrical disorder of the heart. The letter Q on the electrocardiogram represents the time when the electrical impulse signals the heart to contract. The letter T marks the point where the cells of the ventricles are electrically recharging for the next beat.
When the time between the start of the Q wave and the end of the T wave becomes prolonged, the heart becomes sluggish and inefficient. Athletes who have a prolonged QT time are more likely to suffer sudden cardiac death.
“Commotio cordis” is another cause of sudden death. It's like being in the wrong place at the wrong time. In these cases a young athlete is struck in the chest by a baseball, puck or head of an opposing player. If the blow is severe enough, and occurs at the wrong time in the heart's electrical cycle, ventricular fibrillation can occur.
Dr. Ackerman says that all too often these sudden deaths occur without any advance warnings. And that there is no 100 percent perfect way to spot this potential problem. However, there are two red flags to watch for.
The first is sudden and unexplained fainting during physical exertion such as a race. Or when these fainting spells are associated with seizures.
A second warning sign is when there is a family history of unexplained deaths before the age of 50. In other cases there may be exercise-induced shortness of breath or chest pain. But these are common symptoms and it's hard to tell them apart from problems such as asthma.
Dr. Ackerman admits there's no consensus on the best way to prevent these tragic deaths. Some countries such as Japan and Italy use the electrocardiogram in an attempt to find those athletes most susceptible to sudden death. But this can unnecessarily worry athletes when initial results look suspicious, even though they eventually turn out to be normal.
Athletes identified as high risk may be prescribed beta blockers that affect the heart's rate. Or doctors may suggest implanting a cardioverter defibrillator into the chest to restart the heart should ventricular fibrillation occur. Some athletes may decide the risk is too high and avoid sporting activities altogether.
In one third of cases pathologists are unable to find why death has occurred. The final death certificate then reads, “Sudden unexplained death”.
W. Gifford-Jones M.D is the pen name of Dr. Ken Walker graduate of Harvard. Dr. Walker's website is: Docgiff.com
My book, �90 + How I Got There� can be obtained by sending $19.95 to:
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