Preterm birth tied to poorer right ventricular remodeling

In children with hypoplastic left heart syndrome, preterm birth appears to be associated with poor right ventricular (RV) remodeling parameters and lower transplant-free survival rates, a new study has found.

The study included 549 patients, of whom 11.7 percent (n=64) were born preterm. Participant data were retrieved from the Single Ventricle Reconstruction trial, focusing on echocardiographic measures at birth and at 14 months. Patients were followed until 6 years of age to assess transplant-free survival.

Right ventricular end-diastolic (RVEDV) and end-systolic (RVESV) volumes were significantly lower in preterm participants, as was the tricuspid valve annulus area. However, when looking at index values, only RVEDV index remained significantly lowered in preterm participants (72.0 vs 85.2 mL/m²; p=0.019).

This trend was reversed by 14 months of age, such that RVEDV index was higher in preterm-born participants at 14 months (100 vs 85.2 mL/m²; p=0.029).

Over a median follow-up of 5.93 years, 212 patients died or underwent heart transplantation. Most (81.8 percent) of these occurred in the first year of life. Kaplan-Meier survival analysis showed that transplant-free survival was significantly worse in the preterm group (p<0.001).

This was confirmed by Cox regression analysis, which showed that preterm birth more than doubled the risk of death or heart transplantation (hazard ratio, 2.14, 95 percent confidence interval, 1.51–3.04; p<0.001). Adjusting for genetic syndromes or non-syndromic anomalies did not attenuate this interaction and those born preterm remained twice as likely to die or need heart transplant.