Rheumatic Heart Disease in Pregnancy — OB/GYN Quick Quiz

The risk of maternal mortality is as high as 3%. She warrants bimonthly echocardiography, because she has a high risk of cardiac failure that increases as the pregnancy progresses and can quickly cause pulmonary edema

Mitral stenosis is poorly tolerated in pregnancy and carries an overall maternal mortality of 3%, with mortality risks of up to 6% in high-risk women with poor baseline functional status. Morbidity and mortality are largely due to cardiac failure and the subsequent development of pulmonary edema and pulmonary hypertension. Patients with mitral stenosis in pregnancy require regular clinical and echocardiographic monitoring. The risk of cardiac failure increases as the pregnancy progresses, and the highest risk is seen in women who have a valve area of less than 1.5 cm2.

Although medical management with beta blockers and diuretics is usually the first line of treatment, percutaneous mitral commissurotomy can be safely undertaken in pregnancy, although, if possible, the procedure should be delayed until after 20 weeks of gestation. The main indication for percutaneous mitral commissurotomy is development of pulmonary artery hypertension, and the procedure should be considered when pulmonary arterial pressures rise above 50 mm Hg despite optimal medical therapy. The procedure should take place in a specialist center with an experienced operator and use abdominal shielding to limit screening time, reducing the risk of radiation exposure.

Although epidural anesthesia can be helpful in labor to reduce maternal heart rate and blunt sympathetic responses to pain, hypovolemia is poorly tolerated in these patients. Careful administration of epidural anesthesia will help avoid a sudden drop in preload.

The high risk of thromboembolism warrants anticoagulation in women with atrial fibrillation or a dilated left atrium. The risk of developing atrial fibrillation is approximately 15% in this population group. This patient does not require anticoagulation at this point, but it would be necessary should she develop atrial fibrillation or left atrial dilatation.

References:

Chang PP, Kelly EA. Cardiovascular disease in pregnancy. In: Runge MS, et al. Netter's Cardiology. 2nd ed., 2010: 489-498.

European Society of Gynecology; Association for European Paediatric Cardiology; German Society for Gender Medicine, et al. ESC guidelines on the management of cardiovascular diseases during pregnancy: the task force on the management of cardiovascular diseases during pregnancy of the European Society of Cardiology. Eur Heart J. 2011; 32(24):3147-3197.

Nanna M, Stergiopoulos K. Pregnancy complicated by valvular heart disease: an update. JAMA. 2014;3(3):e000712.