226 - Cardiac Alterations in Fetuses Exposed to Rheumatic Disease – A Fetal Speckle Tracking Echocardiography Study.

Fetuses exposed to maternal rheumatological conditions, especially in the presence of anti-Ro/La antibodies (Ab+), are at risk of perinatal complications. Speckle-tracking echocardiography (STE) assesses cardiac function by quantifying myocardial deformation in length (strain) and speed (strain rate).

Objective:

Evaluate the fetal cardiac performance in pregnancies complicated by a maternal rheumatological condition using STE, compared to a cohort of fetal controls. Also, to characterize the effect of circulating maternal autoantibodies and fetal heart block (HB) on fetal cardiac function.

Design/Methods:

Single-center, retrospective study of women with rheumatic disease who underwent fetal echocardiography during pregnancy between 2013 to 2021. Pregnancies were stratified by anti-Ro/La antibody status and were compared to fetal controls, which were matched by gestational age (22 to 24 weeks).

Results: We identified 60 pregnancies exposed to a rheumatological condition and 61 controls. Of rheumatic disease pregnancies, 46 had positive autoantibodies (Ab+) including 3 twin pregnancies, resulting in 49 Ab+ fetuses.  Most pregnancies occurred in the context of systemic lupus erythematosus (65%) and 83% were exposed to hydroxychloroquine (Table 1). Left ventricular (LV) ejection fraction (EF) was higher in fetuses exposed to rheumatological conditions, regardless of Ab+ status, compared to controls (Table 2). Ab+ fetuses also showed increased LV deformation (global and LV free wall) compared to controls. Right ventricular (RV) parameters were similar between groups. Within the Ab+ fetuses, 5 (11%) had a third-degree HB (Table 3). These ECHO demonstrated a delayed LV and RV activation of the time-to-peak deformation by STE. Ab+ fetuses without HB still demonstrated an increased LV-EF when compared to controls (LV-EF 56% [SD 10] vs 52% [SD 8]; p=0.01); 95% CI: [53, 59]% vs [50, 54]%) and LV anterolateral peak longitudinal strain (-24.13 [SD 6.5] vs -21.83 [SD 5.1]%; p=0.04); 95%CI: [-26.1, -22.2]% vs [-23.1, -20.5]%).

Conclusion(s): Fetuses exposed to maternal rheumatological conditions show early cardiac functional alterations by STE, regardless of HB status. The increase in LV-EF and strain may represent changes due to an adverse in-utero environment. Indeed, these findings may reflect an early adaptation to a higher afterload secondary to adverse vascular resistance. Future studies should outline the later gestational and immediate post-natal cardiac adaptation of infants exposed to maternal rheumatological diseases.