Impact of gestational diabetes mellitus on maternal cardiac adaptation to pregnancy

Objective To determine whether maternal cardiac adaptation at term differs between women with, and those without, gestational diabetes mellitus (GDM). Methods This was a prospective case- control study of pregnant women at term with or without GDM. For both cases and controls, only women without any comorbidity or form of pre-existing diabetes who had a singleton pregnancy without complication (such as pre-eclampsia or fetal growth restriction) were included. All women underwent conventional and speckle-tracking echocardiography to assess both the left- and right-heart geometry and function. Results A total of 40 women with GDM and 40 healthy controls were enrolled. Women with GDM, compared with controls, had a significantly higher heart rate (83 +/- 10 vs 75 +/- 9 beats per min; P< 0.001), left ventricular (LV) relative wall thickness (0.43 +/- 0.07 vs 0.37 +/- 0.08; P< 0.001), LV early diastolic transmitral valve velocity (E) (0.80 +/- 0.15 vs 0.73 +/- 0.12 m/s; P= 0.026) and LV late diastolic transmitral valve velocity (A) (0.65 +/- 0.13 vs 0.57 +/- 0.11 m/s; P= 0.006). In women with GDM compared with controls, speckle-tracking analysis revealed a significant reduction in LV global longitudinal strain (GLS) (-16.29 +/- 2.26 vs -17.61 +/- 1.89; P= 0.012), LV endocardial GLS (-18.50 +/- 2.59 vs -19.84 +/- 2.35; P= 0.031) and LV epicardial GLS (-14.40 +/- 2.01 vs -15.73 +/- 1.66; P= 0.005). Right ventricular (RV) analysis revealed a reduced pulmonary acceleration time (58 +/- 10 vs 66 +/- 11 ms; P= 0.001) and RV E/A ratio (1.13 +/- 0.18 vs 1.29 +/- 0.35; P= 0.017), as well as a higher RV myocardial systolic annular velocity (0.16 +/- 0.04 vs 0.14 +/- 0.02; P= 0.023) and peak late diastolic transtricuspid valve velocity (0.46 +/- 0.1 m/s vs 0.39 +/- 0.08 m/s; P= 0.001), in women with GDM compared to controls. Conclusions Our findings show that even a short period of exposure to hyperglycemia, as occcurs in women with GDM, is associated with significant maternal functional cardiac impairment at term. Given these findings, further study of postnatal maternal cardiovascular recovery after GDM pregnancy is warranted. Copyright (C) 2019 ISUOG. Published by John Wiley & Sons Ltd.