RÉSUMÉ
Objective:To assess the altered right atrial(RA) function using two-dimensional speckle-tracking imaging(2D-STI) in patients with persistent pulmonary hypertension of the newborn(PPHN), and investigate the diagnostic value of different right heart strain parameters in PPHN.Methods:Ultrasound images of 42 newborns with clinically confirmed diagnosis of PPHN in the neonatal intensive care unit of Shenzhen Children′s Hospital (median gestational age 37 + 1 weeks, median age 6 d) and 30 normal newborns (control group, median gestational age 37 + 3 weeks, median age 6.5 d) from January 2020 to January 2023 were retrospectively analyzed, all with gestational age ≥34 gestational weeks. 2D-STI was applied to evaluate RA function: RA strain(RA LS) and area change fraction(RA FAC), where RA LS included RA reservoir strain (εs), RA conduit strain (εe) and RA active contract strain (εa), while evaluating right ventricle(RV) function: RV global longitudinal strain(RV GLS), RV FAC, etc. And the degree of pulmonary artery pressure(PAP) was assessed by tricuspid regurgitation velocity(TRV). The above parameters were compared between the PPHN group and the control group, and the correlations between RA function parameters, RV function parameters and PAP in PPHN group were analyzed. The area under ROC curve (AUC) was used to compare the accuracy of each parameter in the evaluation of impaired cardiac function in PPHN patients. Results:Compared with the control group, RA function (εs, εe, εa and RA FAC) were impaired in PPHN patients (all P<0.05). εs was positively correlated with RV GLS, RA FAC ( r=0.494, 0.356, both P<0.05) and negatively correlated with minimum right atrial area (RAA min), pulmonary artery diameter (PAD), and tricuspid annular internal diameter ( rs=-0.285, r=-0.495, -0.396; both P<0.05); εe was negatively correlated with PAD ( rs=-0.256, P<0.05); εa was positively correlated with RV GLS ( r=0.499, P<0.05) and negatively correlated with PAD and tricuspid annular internal diameter ( r=-0.390, -0.380; both P<0.05); RA FAC was positively correlated with RV GLS ( r=0.365, P<0.05) and negatively correlated with PAD and tricuspid annular internal diameter ( r=-0.439, -0.328; both P<0.05). RA LS and RA FAC had no correlations with TRV-estimated PAP ( P>0.05). ROC analysis showed that the sensitivity and specificity of εs<40.50% for diagnosing PPHN was 0.905 and 0.800, respectively, with an AUC of 0.929; the sensitivity and specificity of RV GLS<18.55% for diagnosing PPHN were 0.905 and 0.900, respectively, with an AUC of 0.963; εs combined with RV GLS was the best indicator for early detection of right heart functional impairment in PPHN, with sensitivity and specificity of 0.905 and 1.000, respectively, and AUC was 0.985. Conclusions:RA function and RV function are both impaired in PPHN patients. εs combined with RV GLS is the best indicator for early assessment of right heart function impairment and diagnosis of PPHN.