Preemie heart damage could be reversed with exercise in young adulthood

Cardiac abnormalities stemming from preterm birth can be corrected with a three-and-a-half-month exercise program in patients’ teens and twenties, according to a drug-free trial of Canadian adults.

Babies born more than two months early—considered “very preterm”—are prone to heart abnormalities that can ultimately increase their lifetime risk of CVD, lead investigator Elizabeth Hillier, of McGill University in Montreal, Canada, said in a release. Up until now, researchers didn’t know if that damage was permanent or whether it could be corrected.

Hillier’s team, who recently presented their findings at the European Society of Cardiology’s EuroCMR 2019 conference in Venice, Italy, enrolled 14 young adults aged 18 to 29 for their study, which tested whether a 14-week exercise program could improve cardiac function in kids born very prematurely. Eight of the participants were preemies; the other six acted as controls.

During the study, all adults stuck to a program of aerobic and resistance training three times a week, including two supervised 90-minute group exercise sessions and one home-based monitored session. The program was designed around Canadian exercise guidelines, which recommend at least 150 minutes of moderate-to-vigorous physical activity per week.

Before and after participants completed the program, Hillier and her colleagues measured their hearts’ structure and function with cardiovascular magnetic resonance (CMR) imaging. CMR was performed during 60 seconds of hyperventilation followed by a breath-hold—an approach designed to assess how the heart functions under stress.

“With this technique we can detect even mild abnormalities and track the response to interventions,” Hillier said. “Unlike other methods, we did not have to inject a dye, no radiation was used and we did not need to administer drugs to put the heart under stress.”

As expected, adults who were born prematurely had worse cardiac structure and function at the study’s baseline than controls. But by the time the trial wrapped, those patients’ pumping and contracting functions normalized, and CMR showed their hearts were working as effectively as controls’.

“We found that a short exercise program may improve overall cardiac performance and subtle abnormalities in cardiac function in preterm adults,” Hillier said. “Advances in neonatal care have enabled premature babies to survive, but the abnormal shape and function of the heart is sustained. Exercise in early adulthood corrects these impairments, which should reduce the risk of cardiovascular disease.”