A team of specialists with expertise in the cardiac disorders in pregnancy should be involved early and throughout the pregnancy. Intermediate- to high-risk cardiac patients have an increase in obstetric complications as well, including gestational hypertension and preeclampsia, preterm labor, and postpartum hemorrhage. There is also an increased risk of neonatal complications including intrauterine growth restriction and low birth weight, premature delivery, respiratory distress, intraventricular hemorrhage, and death [4].

Based upon outcomes reported in the literature which includes single center experience, registry data in Europe, and prospective studies in Canada, patients can be grouped into high-, intermediate-, and low-risk groups (Table 1.2). For a specific individual, the exact cardiac condition will dictate risk and management. It can be useful to categorize these diseases into groups, which behave similarly and are outlined in Table 1.3. Congenital defects include atrial septal defects, ventricular septal defects, tetralogy of Fallot, transposition of the great arteries, coarctation of the aorta, and several other illnesses; these represent a growing number of patients because of advanced care during childhood, so patients are now surviving into adulthood. Aortic diseases include Marfan syndrome, Ehlers-Danlos syndrome, Turner syndrome, and bicuspid aortic valve. Cardiomyopathies include peripartum and idiopathic. Arrhythmias encompass both tachycardias and bradycardias. Acute coronary syndrome can occur during pregnancy, both from unstable plaques and from dissection. Hypertension can become worse during pregnancy. Thrombosis can occur (both arterial and venous) because of increased hypercoagulability during pregnancy (refer to Heme chapter).