Cardiac remodelling and reverse remodelling in pregnant women: what can be expected?
Authors: Ferreira A F , Azevedo M J , Proenca T , Saraiva F A , Machado A P , Sousa C , Sampaio Maia B , Leite-Moreira A , Ramalho C , Fa I 
Published: October 2021

Abstract

Introduction
Hemodynamic overload during pregnancy induces cardiac remodelling which is characterized by left ventricle (LV) eccentric hypertrophy and left-atrium enlargement.After delivery,the woman's heart undergoes reverse remodelling and myocardial performance normalize to their pre-gravid structure and function.

Aim
To characterize cardiac remodelling and reverse remodelling during pregnancy and postpartum, respectively, as well as to investigate the impact of cardiovascular (CV) risk factors in these processes.

Methods
This prospective cohort study included volunteer pregnant women recruited in a tertiary centre between 2019 and 2020.Women were evaluated by transthoracic echocardiography and pulse wave velocity at the 1st trimester [1T, baseline], 3rd trimester [3T, peak of CV remodelling] of pregnancy as well as at the 1st month and 6th month after delivery (reverse remodelling). Mann-whitney,wilcoxon and Ffriedman test were used as appropriate to between and within groups comparisons. Bonferroni correction was applied. Spearman correlation was performed to determine the relationship between pulse wave velocity (PWV) and echocardiographic variables.

Results
We included 32 pregnant women with a median age of 34 [26; 41] years, 50% being hypertensive and/or obese. The pregnant women tended to develop eccentric hypertrophy pattern during pregnancy, characterized by significant increase of cardiac mass index (CMi) from 1T to 3T (table 1, p=0.006) and slight modification of relative wall thickness (RWT, table 1, p=0.339). During postpartum, hypertrophy regression became significant only at 6 months after delivery (CMi: table 1, p&lt;0.001; RWT: table 1, p&lt;0.001). In contrast, a fastest recovery of indexed left atrial (3T to 1 month postpartum:table 1,p=0.033) and ventricular volumes (table 1, p&lt;0.001) was observed after delivery, despite its slight enlargement during pregnancy (atrium-table 1, p=0.55; LV-table 1, p=0.084). RWT correlated positively with PWV at 3T (r=0.447, p=0.012). Compared to the healthy pregnant women,CV risk factors group showed higher RWT in all time points of follow-up period,without any differences in CMi and cardiac volumes indexed. Filling pressures increased during gestation (table 1, p=0.002),normalizing as soon as 1 month after delivery (table 1, p=0.001) and maintained at the 6th month (table 1, p&lt;0.001). Pregnant women with CV risk factors revealed a significant higher value of E/e' in comparison with the healthy group, but only at the 6th month of postpartum (5.6 [5.2; 8.2] vs 5.4 [4.4; 7.7], p=0.036).

Conclusion
In our cohort, complete reverse remodelling occurs as soon as one month after delivery, with the exception of hypertrophy.The positive correlation between relative wall thickness and pulse wave velocity highlighted arterial-ventricular coupling relevance for the cardiac remodelling process during pregnancy. Pregnant women with CV risk factors showed higher relative wall thickness when compared with healthy women at all time points of the follow-up.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Universidade do Porto/FMUP and FSE-Fundo Social Europeu; FCT - Foundation for Science and Technology