Preterm birth leaves lasting impressions on heart

Infants born preterm and with very low birthweight (VLBW) appear to sustain altered cardiovascular structure and function in adulthood, a new study has found.

Drawing from the New Zealand VLBW study, the researchers assessed 229 adults (aged 26–30 years) who were of VLBW at birth. Systolic (SBP) and diastolic (DBP) blood pressure was measured by a blinded observer, while microcirculatory responses were evaluated using peripheral arterial tonometry. Participants also underwent transthoracic echocardiography. A hundred term controls were also included.

SBP was significantly elevated in the VLBW adults (mean, 121.6±14 vs 117.6±13 mmHg; p=0.046), while DBP was comparable (p=0.152). Mean cardiac output was likewise lower in the former group (4.8±1.2 vs 5.1±1.4 L/min; p=0.03), while ejection fraction was not (p=0.37).

Cardiovascular structure also differed between VLBW and term controls even after indexing for body surface area and controlling for sex. For instance, left ventricular (LV) mass index was significantly higher in controls (96.91 vs 90.48 g; p=0.006), as were the LV end-systolic (23.08 vs 21.01 mL; p=0.0005) and end-diastolic (63.40 vs 58.70 mL; p=0.0003) volumes.

LV and arterial elastance were both significantly elevated in VLBW participants than in term controls (p=0.000 for both).

“Our study confirms that premature birth is associated with differences in cardiovascular structure and function that are apparent in early adulthood when cardiovascular function peaks and after which cardiovascular risk starts to increase significantly,” the researchers said. This population may be more susceptible to pathological cardiovascular conditions as they age.