Caracterização da Função Auricular Esquerda durante a Remodelagem Cardíaca e Remodelagem Reversa induzida pela Gravidez

Abstract

Introduction: A hallmark of pregnancy is a hemodynamic overload that leads to cardiovascular remodeling, characterized by enlargement of left atrial (LA) and ventricular (LV) volumes associated with impaired LV relaxation, maintaining preserved systolic function. These changes are reversible during postpartum. Yet, few scientific evidence is published about LA function. Aim: Assess the LA function, through two-dimensional speckle tracking echocardiography analysis during pregnancy and its recovery up to 1 year after delivery; as well as determining its potential predictors. Methods: This prospective cohort study included volunteer pregnant women (healthy, obese and/or hypertensive and/or with gestational diabetes) recruited in two tertiary centers between 2019 and 2022. Participants were evaluated by transthoracic echocardiography and pulse wave velocity at the 1st trimester [1T, 10-15 weeks, baseline], 3rd trimester [3T, 30-35 weeks, peak of cardiac remodeling] of pregnancy as well as at the 1st, 6th and 12th month after delivery, during reverse remodeling (RR). Generalized linear mixed-effects models evaluate the cardiovascular remodelling and RR, including the variation of left atrial strain and its potential predictors. Results: We included 148 pregnant women with a median age of 34 [30,37] years, being 60,1% primiparous. Sixty-three (42.6%) were diagnosed with at least one cardiovascular risk factor. Regarding LA function, a significant reduction of LA strain was verified from 1T to 3T (35.86 [31.20, 41.10] % to 32.54 [28.60, 36.20] %, p<0.001), recovering 6 months postpartum (32.54 [28.60, 36.20] % to 33.92 [29.80, 37.90] %, p=0.035). A significant enlargement of LA volume (43 [36, 48]mL/m2 to 50 [43, 56]mL/m2, p<0.001) associated with increase of E/e' (5.89 to 6.68, p<0.001) was observed from 1T to 3T, recovering both as soon as 1 month after delivery (LA volume: 50 [43, 56]mL/m2 to 42 [34, 49] mL/m2, p<0.001; E/e': 6.68 [5.41, 7.82] to 5.83 [4.79, 6.46, p<0.001). In addition, participants developed a LV hypertrophy during gestation (1T to 3T, LV mass: 105 [93, 117] g to 130 [110,145]g , p<0.001; relative wall thickness: 0.32 [0.28, 0.35] to 0.36 [0.31, 0.40] , p<0.001) with significant regression as soon as 1 month after delivery (LV mass: 130 [110, 145] g to 116 [101, 129] g , p<0.001; relative wall thickness: 0.36 [0.31, 0.40] to 0.33 [0.3, 0.37] , p<0.001). Systolic function was preserved during the follow-up period. Systemic vascular resistance was identified as independent predictor of LA strain (-2.61 [-4.70, -0.52], p=0.015). Conclusion: Despite E/e' ratio and LA volume recovered 1 month after delivery, the LA strain only improved 6 months later. The systemic vascular resistance was an independent predictor of LA strain.