Preterm birth associated with smaller right ventricle size, greater mass in adult life
Young adults born preterm have significant differences in global myocardial structure and function, and the effect is greater the earlier the birth, according to results of a prospective study.
Previous research has shown that people born preterm have different left ventricular mass, function and geometry compared with those born at term. The new findings suggest that differences are more pronounced for the right ventricle than the left ventricle.
“The last trimester is particularly relevant for global cardiac growth,” Adam J. Lewandowski, BSc, DPhil, and colleagues wrote. “The variation in structure and function accounted for by gestational age was greater for the right ventricle [than for the left ventricle], which may relate to its more substantial remodeling around the time of birth.”
The researchers studied 102 young adults who were born before term between 1982 and 1985. All were followed-up prospectively since birth until an average age of 25 years. They also recruited 102 young adults born at term who were of similar age and sex distributions and 30 adults born at term a decade earlier who were of similar sex distribution. For this study, a baby born before the 37th week of pregnancy was considered premature. Participants filled out questionnaires on medical history and other topics and had blood samples and BP measurements taken. Right ventricular structure and function was quantified by CV magnetic resonance using a 1.5-T Siemens Sonata scanner.
Young adults born preterm had a smaller right ventricle than those born at term (end diastolic volume: 79.8 ± 13.2 mL/m2 vs. 88.5 ± 11.8 mL/m2; P<.001). However, preterm-born participants had greater right ventricular mass than participants born at term (24.5 ± 3.5 g/m2 vs. 20.4 ± 3.4 g/m2; P<.001). For both of these factors, the differences were more severe related to earlier gestational age (r=–0.47; P<.001).
“Differences in right ventricular mass and function were proportionally greater than previously reported for the left ventricle,” the researchers wrote.
Preterm-born participants had lower right ventricular ejection fraction than participants born at term (57 ± 8% vs. 60 ± 5%; P=.006). Twenty-one percent of preterm participants had an EF less than the lower limit of normality as defined by the term-born participants of the same age, and 6% of the preterm participants met the criteria for mild right ventricular systolic dysfunction (range, 42% to 45%).
The researchers determined that postnatal ventilation could account for some of the differences in mass, but not in function.
Further research is needed to better understand the mechanisms that underlie the changes in CV structure and function observed in preterm-born young adults, Lewandowski and colleagues wrote. This “will help determine possible pathways to prevent future disease in the growing cohort of adults born preterm,” they wrote.
Disclosure: The researchers report no relevant financial disclosures.