Reverse remodelling of right ventricle induced by pregnancy

Abstract Introduction During pregnancy, the cardiovascular (CV) system is exposed to haemodynamic overload and is required to meet the increased demands of the growing foetus. Many studies have focused on left ventricular remodelling, overlooking right cardiac chamber changes. Aim To characterize the right cardiac reverse remodelling (RR) through echocardiography during pregnancy and postpartum. Methods This prospective cohort study included volunteer pregnant women (healthy and women with CV risk factors - obese and/or hypertensive and/or with gestational diabetes) recruited at two tertiary centres from 2019 to 2021. Women were evaluated by transthoracic echocardiography at the 3rd trimester [PT3, 30-35 weeks, peak of cardiac remodelling] of pregnancy and 6 months after delivery [PP2] (RR). Wilcoxon test was used to compare values between PT3 and PP2. Results We included 130 pregnant women with a median age of 33 years, 42% had CV risk factors. RV volume reduced significantly from PT3 to PP2 (33.9 mL to 30.5 mL, p=0.015). Similar significant regression of RA area was observed (13.6 cm2 to 13.1 cm2, p=0.045). Regarding systolic function of the RV, a significant increase in fractional area change (FAC) was reported from PT3 to PP2 (47.4% to 49.4%, p=0.019), while the opposite progression was found for tricuspid annular plane systolic excursion (TAPSE, 24.6 mm to 23.4 mm, p<0.001) and S' tricuspid wave (14.2 cm/s to 12.7 cm/s, p<0.001). In terms of myocardial deformation, a significant increase of RV global longitudinal strain (GLS) (-23% to -25%, p=0.016) and RA (34% to 37%, p=0.026) from the pre- to the postpartum period. Regarding the changes in diastolic function, E/A tricuspid ratio increased significantly after delivery (1.3 to 1.7, p<0.001), mostly due to a decrease of A wave velocity (38 cm/s to 29 cm/s, p<0.001), while no significant difference was found in E/e’ from PT3 to PP2 (3.8 to 3.7, p=0.140). No differences were observed in pulmonary vascular resistance and pulmonary artery systolic pressure (1.3 woods in both and 18 mmHg in both, respectively). Conclusion We report a significative regression of right chambers size up to 6 months after delivery. Pregnancy significantly impacts right systolic function as assessed by decreased FAC and strain analysis with a compensatory increase of TAPSE. Right diastolic function reflects pregnancy adaptation to volume overload as observed by the augmented velocity of atrial contraction.