Cardiac performance is impaired in morbidly obese pregnant females

To evaluate the effect of pregnancy on ventricular function in morbidly obese as compared to lean controls.

We serially studied 33 obese and non-obese pregnant females with echocardiography during each trimester of pregnancy and after delivery. Two well-validated, relatively load-independent indices of contractility (systolic shortening index and systolic velocity index) were assessed, along with more traditional echocardiographic parameters. ANOVA for repeated measures was used to compare data between sequential studies in the normal and obese pregnant groups.

In lean controls, stroke volume increased and contractility was maintained during pregnancy as compared to pre-pregnancy levels. In contrast, both stroke volume and contractility declined significantly by the third trimester in morbidly obese females.

There is a maladaptive left ventricular contractile response to pregnancy in morbidly obese patients.