41^st World Cardiology Conference

Cardiovascular Diseases during Pregnancy

The evaluation of individuals with valvular heart disease who are or wish to become pregnant is a problematic issue. Issues that have to be addressed include the risks in pregnancy to the mother and the increasing foetus by the presence of maternal valvular heart disease as an intercurrent disease in pregnancy. Common physiological variations during pregnancy require, on average, a 50% growth in circulating blood volume that is supplemented by an increase in cardiac output that usually peaks between the mid portion of the second and third trimesters The enlarged cardiac output is due to an increase in the stroke size, and a minor increase in heart rate, averaging 10 to 20 beats per minute. Additionally uterine circulation and endogenous hormones cause systemic vascular resistance to reduction and a disproportionately lowering of diastolic blood pressure causes a catholic pulse pressure. Inferior vena canal obstruction from a gravid uterus in the prone position can result in an abrupt decrease in cardiac preload, which leads to hypotension with weakness and light headedness. During lab or and delivery cardiac output rises more in part due to the related anxiety and pain, as well as due to uterine reductions which will cause an increase in systolic and diastolic blood pressure.