Cardiac Performance in Pregnant Obese Women:Are They in Jeopardy?

Overweight and obesity are defined as: abnormal or, excessive fat accumulation that presents a risk to health. A crude population measure of obesity is the body mass index (BMI), a person's weight (in kilograms) divided by the square of his or her height (in meters). A person with a BMI of 30 or more is generally considered obese. A person with a BMI equal to or more than 25 is considered overweight.

Obesity has reached particularly alarming levels in the Middle East and North Africa (MENA) region. The prevalence of female obesity currently estimated at over 40% , had already exceeded that in Europe and the USA.

Obesity has been linked to several major chronic diseases, including type II diabetes, cardiovascular diseases, selected cancers, gallbladder disease, asthma, osteoarthritis, and chronic back pain.

Obesity has been also linked to a wide spectrum of cardiovascular changes ranging from a hyper dynamic circulation, through subclinical cardiac structural changes, to overt heart failure.

Obesity is associated with hemodynamic overload due to the increased metabolic demand imposed by the expanded adipose tissue and augmented fat-free mass in obesity results in a hyper dynamic circulation with increased blood volume. In addition to the increased preload, left ventricular (LV) after load is also elevated in obese individuals due to both increased peripheral resistance and greater conduit artery stiffness. Right ventricular after load may be increased, presumably due to associated sleep disordered breathing and LV changes.

Pregnancy is associated with hemodynamic and hormonal changes that can affect the heart. From the first trimester, there is an increase in cardiac output that places a volume load on the heart. Hormonal changes include increased circulating estrogen and relaxin, which may directly or indirectly affect the heart. During pregnancy, the heart undergoes remodeling similar to that observed in athletes, with increases in chamber dimensions, left ventricular (LV) wall thickness, and mass, that is consistent with a process of eccentric hypertrophy.

Myocardial contractile function also changes in pregnancy. Ejection-phase indices of LV function, including systolic fractional shortening (FS) and mean velocity of circumferential fiber thickening (V CFC), have been variously reported to increase, remain constant,or decrease, during pregnancy. Thus, obese women are more likely to encounter problems on becoming pregnant.

There is large evidence in the literature demonstrating that women who are overweight are at greater risk of developing pregnancy complications and problems associated with labor and delivery.

Inclusion criteria

• Any pregnant woman in her 1st trimester with a singleton live healthy pregnancy

Exclusion criteria

• Multiple gestations.
• Anemia.
• Medical history of hypertension.
• Medical history of any cardiac disease.
• Medical history of pre-gestational diabetes.
• Development of gestational diabetes and pre-eclampsia.