Babies who are born prematurely experience differences in how their heart forms and works as an adult, compared with babies who are born at full-term. According to a study published in the journal Circulation, this leads to a higher risk of cardiovascular disease later in life.
Researchers from the University of Oxford in England studied 102 premature infants from birth, alongside 132 infants who were born at full-term with no complications.
Of the premature infants, 14% were born at less than 28 weeks, 58% were born between 28 and 31 weeks, and 31% were born between 32 and 36 weeks.
All infants were born in the 1980s and tracked until they were between 23 and 28 years of age.
As well as standard heart health evaluations, which included measurements of blood pressure and cholesterol, the researchers used magnetic resonance imaging (MRI) techniques in order to measure the participants' hearts and blood vessels.
They used computer programs to create models of the hearts, enabling them to investigate their structure and see how much blood was being pumped around the body.
Results of the analysis revealed that the right ventricle - the part of the heart that receives deoxygenated blood from the right atrium and pumps it to the lungs - was significantly different in the adults who were premature babies, compared with the hearts of adults who were born at full-term.
The premature babies had hearts that were smaller, heavier and had thicker walls with reduced pumping activity.
Additionally, the scientists found that the earlier the former premature babies were born, the bigger the impact was on the size and function of the right ventricle.
Professor Paul Leeson, a cardiologist at the Cardiovascular Clinical Research Facility of the University of Oxford, says that around 10% of today's adults are born prematurely and appear to be at higher risk of cardiovascular problems in adulthood.
The scientists say that in older adults, changes in the structure of the right ventricle may lead to increased risk of heart failure and cardiovascular death.
"We wanted to understand why this occurs so that we can identify the small group of patients born premature who may need advice from their healthcare provider about this cardiovascular risk.
The changes we have found in the right ventricle are quite distinct and intriguing."
But they add that there was no evidence of such problems in the young people who participated in the study.
The study authors conclude that further analysis is needed to enhance understanding of the structure of the hearts in premature babies, and how their risk of cardiovascular can increase in adulthood.
"We are trying to dig deeper into what's different about the hearts of those born preterm," says Adam Lewandowski, first author of the study.
"The potential scientific explanations for why their hearts are different are fascinating and our study adds to the growing understanding of how premature birth shapes future heart health."