Obesity in pregnancy is a predictor of persistent subclinical myocardial dysfunction over postpartum period

No previous study provided a complete functional evaluation of all cardiac chambers in pregnant women with obesity. Moreover, the impact of cardiovascular changes associated with obesity in pregnancy on maternal outcome is unclear.

46 consecutive pregnant women with obesity, defined by body mass index (BMI) ≥ 30 Kg/m², and 83 age- (35.5 ± 4.1 vs. 34.1 ± 5.1 yrs, p = 0.11), ethnicity- (caucasian 65.2 vs. 66.3%, p = 0.90) and gestational week-matched (36.3 ± 1.7 vs. 36.5 ± 1.5 wks, p = 0.49) pregnant women without obesity (BMI < 30 Kg/m²) were examined in the first trimester (12-14 weeks), third trimester (36-38 weeks) and 6-10 weeks postpartum. All women underwent obstetric visit, blood tests and transthoracic echocardiography implemented with two-dimensional speckle tracking echocardiography analysis of biventricular and biatrial myocardial deformation indices at the three time points. Outcome was persistent subclinical myocardial dysfunction, defined as an absolute value of left ventricular global longitudinal strain (LV-GLS) less negative than - 20%, in postpartum.

Despite normal biventricular systolic function, all myocardial strain indices were significantly lower in pregnant women with obesity than controls. At 8.2 ± 2.2 weeks postpartum, LV-GLS remained less negative than - 20% in 86.9% of women with obesity in pregnancy. Maternal age (OR 1.68, 95%CI 1.14-2.48), third trimester BMI (OR 7.17, 95%CI 1.77-28.9) and third trimester neutrophil-to-lymphocyte ratio (NLR) (OR 1.75, 95%CI 1.22-2.51) were independently associated with outcome. Maternal age ≥ 35 years, BMI ≥ 30 Kg/m² and NLR ≥ 5.5 were the optimal cut-off values for predicting persistent subclinical myocardial dysfunction in postpartum.

Pregnant women with obesity, age ≥ 35 yrs and low chronic inflammation have significantly increased risk of persistent subclinical myocardial dysfunction over postpartum.