Healthy, older adults free of heart disease need not fear that bouts of rapid, irregular heartbeats brought on by vigorous exercise might increase short-term risk of dying or having a heart attack, says a new study.
In the new study, researchers at Johns Hopkins and the U.S. National Institute on Aging (NIA) monitored for on average 12 years the medical records of 2,234 initially healthy men and women, ages 21 to 96, and participating in the NIA's Baltimore Longitudinal Study of Aging.
In adults with no earlier signs of heart disease, researchers found no adverse effects resulting from brief episodes of exercise-induced errant heart rhythms, more formally known as non-sustained ventricular tachycardia.
In the study, each volunteer participant had a least one exercise stress test performed before 2001. The test assesses the heart's pumping ability, requiring participants, whose average age at testing was 52, to walk or jog on a treadmill at increasing speeds and inclines until they felt exhausted, about 10 minutes for most.
Eighty-one participants experienced short periods of rapid, irregular heartbeats during exercise, typically lasting from three to six heartbeats, and at a rate hovering around 175 beats per minute.
Researchers say overall death rates were higher in the tachycardia group than in the nontachycardia group.
However, when they adjusted their analysis to account for differences in age, gender, and those who developed known risk factors for heart disease early on, they found no measurable increased risk of overall death, death from heart disease, or suffering a heart attack between the tachycardia and nontachycardia groups.
Study's lead author Joseph Marine says the results should 'provide reassurance' among apparently healthy middle-age and older people that such short episodes of ventricular tachycardia provoked on exercise testing do not have long-term consequences to health.
"So long as a medical examination shows no underlying heart disease or other serious health condition, then people should continue to live a normal lifestyle, including a return to exercise after clearance from their physician," Marine said.
The study has been presented at the American Heart Association's (AHA) annual Scientific Sessions in Orlando.