Young and fit, the runners fix their sights on the finish line: Almost there! A goal about to be realized!
There is magic in this moment for many athletes. But on Nov. 20, 2011, two Philadelphia Marathon runners, both apparently healthy and fit -- one with an under three-hour marathon finish close at hand, the other crossing the finish line with an under two-hour half-marathon -- didn't live to receive their medals and congratulations.
Chris Gleason, 40, an experienced Ironman triathlete and an accomplished runner, collapsed a quarter-mile from his marathon finish and died. Jeffrey Lee, a 21-year-old University of Pennsylvania student, reached his half-marathon finish -- but also died moments afterward.
How can it happen that someone apparently healthy can die as these runners did from sudden cardiac arrest?
"The most common cause of sudden death among athletes is an arrhythmia," an irregular heartbeat, "most often, ventricular tachycardia fibrillation," explains Dr. Harvey Waxman, chief of cardiology at Penn Presbyterian Medical Center and professor of clinical medicine at the University of Pennsylvania Perelman School of Medicine.
With a subspecialty in clinical electrophysiology -- the study of arrhythmias of the heart -- Waxman elaborates that sudden cardiac arrest "can occur in the setting of a structurally normal heart, in which case it is usually caused by a channelopathy," a disturbance of the heart's electrical impulses that "is one of a number of inherited defects."
For example, such defects include Long QT syndrome, catecholaminergic polymorphic VT and Brugada syndrome, says the physician.
Can such deaths be prevented? Darren Sudman, founder of Simon's Fund (www.simonsfund.org ), whose goal is to provide heart screenings for newborns and children, believes they can.
Phyllis and Darren Sudman, whose infant son -- the fund's namesake -- died at only a few months of age from an undiagnosed heart condition, have made it their mission to protect other children from the same fate by making heart screenings "a standard of care for children," according to their website.
Already the screenings have saved lives. Just ask Melissa Fair, Drew Harrington or Kyle McCabe, all diagnosed with heart problems as a result of the free screenings.
Dr. David Shipon, a cardiologist whose focus is on the prevention of heart disease, practices at the Heart Center of Philadelphia, which is affiliated with Thomas Jefferson University Hospital; he is also a board member of Simon's Fund.
He cites the importance of prevention, noting that national screenings in Italy for undiagnosed heart problems and conditions reduced the rate of SCA from 3.6 per 100,000 people to .4.
"The prevention of heart disease starts with the children," he stresses.
Besides regular screenings, Shipon advises educating school officials about risks. Athletic directors, gym teachers and nurses, he says, should alert families of any students showing suspicious symptoms, including shortness of breath, chest tightness or pain, palpitation and fainting for no particular reason.
It is also important, he says, to look at family history. If a relative has died suddenly, it is important to screen other family members for risk factors.
Involvement in high-intensity sports, such as football and basketball, can increase the risk for those with heart abnormalities, says Shipon.
"It is always a balance of risk-benefit with regard to exercise" for a person "with underlying heart disease," explains Waxman.
Certainly, exercise is good for most people with heart disease, he notes. It is really how much and what type of exercise is used that matters.
"For example, if someone has significant" coronary artery disease, "we might recommend daily regular aerobic exercise to a certain level but advise against high-intensity activities, such as competitive sports or marathon running.
"For someone with Marfans Syndrome," which is a genetic trait hampering the connective tissue of the heart, "we would advise against significant isometric exercise and limited aerobic activities."
Those with implanted cardiac defibrillators are advised to have "low-level activities and the avoidance of contact sports."
Shipon says that having an implanted defibrillator can help athletes return to their sport "in modified form."