Reference ranges for fetal tricuspid and mitral annular plane systolic excursions.

Objectives: Echocardiography is the standard tool for assessing fetal cardiac function. Tricuspid annular plane systolic excursion (TAPSE) and mitral annular plane systolic excursion (MAPSE) are simple, reliable indicators of systolic function. Many studies have established reference ranges in adult and pediatric populations; however, data remain limited in fetuses, especially in Southeast Asia. The aim of the study was to establish normal reference ranges for TAPSE and MAPSE in fetuses born between 18 + 0 and 37 + 6 weeks' gestation in a Southeast Asian population.

Methods: This prospective, cross-sectional study was conducted between January 2024 and February 2025. Data from 280 singleton pregnancies with normal fetal growth and no maternal comorbidities were included in the study. TAPSE and MAPSE were measured using M-mode imaging in a four-chamber view. Percentile reference values were determined using quantile regression models, with gestational age (GA) and estimated fetal weight (EFW) as predictors. The intraclass correlation coefficient (ICC) was used to assess intra- and interobserver reliability.

Results: TAPSE and MAPSE were significantly and positively correlated with GA and EFW. Mean TAPSE ranged from 3.76 to 9.08 mm (GA) and 3.42 to 9.30 mm (EFW), while MAPSE ranged from 3.10 to 6.34 mm (GA) and 2.71 to 6.60 mm (EFW). The TAPSE values consistently exceeded the MAPSE values across all GAs. The inter- and intra-observer ICCs were high (TAPSE, 0.94/0.91; MAPSE, 0.91/0.88).

Conclusions: This study established the first normal TAPSE and MAPSE reference ranges for a Southeast Asian population and provided reliable tools for fetal cardiac assessment.