- History of heart disease.
- Symptoms and signs of heart disease.
- Echocardiographic or other objective evidence of heart disease.
Cardiovascular disease occurs in approximately 1% of pregnancies, but the incidence is increasing due to improved prognosis
of women with congenital heart disease and a trend toward older
maternal age. The unique hemodynamic changes associated with pregnancy
make diagnosis and management of heart disease in pregnant patients
a challenge to the physicians, who must consider not only the patient
but also the risks to the fetus.
In general, the normal hemodynamic changes associated with pregnancy are well tolerated by those who have a normal cardiovascular system,
valvular regurgitation, and left-to-right intracardiac shunts. On
the other hand, the highest maternal and fetal morbidity and mortality
is seen with severe obstructive valvular lesions, severe aortic
disease (dilated thoracic aorta or uncorrected coarctation), New
York Heart Association (NYHA) class III or IV heart failure, uncontrolled
hypertension, and cyanotic congenital heart disease. As a rule,
spontaneous vaginal delivery, often with use of vacuum extraction
or forceps to facilitate stage 2 of labor to avoid the hemodynamic stress
associated with pushing, is preferred. Cesarean section, with few
exceptions, should be reserved for obstetric indications.
Stout KK et al. Pregnancy in women with valvular
heart disease. Heart. 2007 May;93(5):552–8.
Normal pregnancy is accompanied by significant physiologic changes, although underlying mechanisms remain virtually unknown (Table 31–1). The normal signs and symptoms associated with pregnancy, such as shortness of breath, fatigue, and exercise intolerance, may obscure the diagnosis of heart disease. The clinician must, therefore, have a thorough knowledge of these normal changes and the aspects of the history and physical examination that suggest the presence of heart disease.
Table 31–1. Cardiovascular Changes in Normal Pregnancy. |Favorite Table|Download (.pdf)
Table 31–1. Cardiovascular Changes in Normal Pregnancy.
| First Trimester|| Second Trimester|| Third Trimester||At Term|
|Blood volume||+||+ +||+ + +||↑ 30–50%|
|Heart rate||+||+ +||+ + (+)||↑ 15–20 beats/min|
|Stroke volume||+||+ + (+)||+|
|Cardiac output||+||+ + (+)||+||↑ 30–50%|
|Systolic blood pressure ||–||–||No change||↓ 5–10 mm Hg mid pregnancy|
|Diastolic blood pressure ||–||– –||–|
|Systemic vascular resistance||–||– – –||– –|
|Pulmonary vascular resistance||–||– –||–|
|Left ventricular end-diastolic pressure||+||+ +||No change|
|Venous compliance and volume||+||+ +||+|
|Red blood cell mass||+||+||+||↑ 15–20%|
The increase in maternal blood volume begins as early as the sixth week of pregnancy, peaks at approximately 32 weeks of gestation,
and stays at that level (40–50% higher than pregestational levels) until delivery. The plasma volume shows a more rapid and ...