In developed countries, cardiovascular diseases are becoming one of the first causes of maternal death. Myocardial infarction, dissection of the thoracic aorta and cardiomyopathies are the leading causes. However, preexisting maternal cardiac diseases, such as congenital heart diseases, are more commonly encountered and may be associated with significant maternal and perinatal morbidity. This article reviews hemodynamic changes occurring during pregnancy, proposes a risk stratification according to pre-existing cardiac diseases, and discusses the monitoring and overall management of these patients. Finally, two pregnancy-triggered cardiac diseases are discussed: coronary artery disease and peripartum cardiomyopathy.