But researchers noted that the fatality rate for cardiac arrest among the runners 71% was lower than other reported rates for out-of-the-hospital incidents of cardiac arrest, which hovered around 92%.

WSJ: Runners, Rest Easy: Heart Risks Seem Overblown

His team explored these risks in a 2009 study -- and found that for both men and women, the rate of cardiac deaths in Los Angeles increased following the city's Super Bowl defeat in 1980.

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The overall rate of heart attacks and cardiac deaths was low to begin with and was not significantly changed by doing the fancy artery imaging.

FORBES: Technology

In fact, because older adults with heart disease often are less able to exercise and have a higher disability rate, they may benefit the most from a cardiac rehabilitation program.

CNN: updated

Despite faster emergency squads, deployment of automated defibrillators at airports and other public places, and improvements in cardiopulmonary resuscitation techniques, fewer than 10% of the 300, 000 Americans who suffer cardiac arrest each year survive long enough to leave the hospital a rate that hasn't budged much over the years.

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