A 29-year-old G1P0 at 28 weeks’ gestation presents to your office complaining of shortness of breath that is more intense with exertion. She has no significant past medical history and is not on any medication. The patient denies any chest pain. She is concerned because she has always been very athletic and cannot maintain the same degree of exercise that she was accustomed to prior to becoming pregnant. On physical examination, her pulse is 72 beats per minute. Her blood pressure is 90/50 mm Hg. Cardiac examination is consistent with a grade I systolic ejection murmur. The lungs are clear to auscultation.
Which of the following is the most appropriate next step in management of this patient?
A. Refer the patient for a ventilation-perfusion scan to rule out a pulmonary embolism (PE)The patient’s symptoms and physical examination are most consistent with physiologic dyspnea, which is common in pregnancy. The increased awareness of breathing that pregnant women experience can occur as early as the end of the first trimester, and is caused by an increase in lung tidal volume. The increase in minute ventilation that occurs during pregnancy may make patients feel as if they are hyperventilating, and may also contribute to the feeling of dyspnea. The patient in this case needs to be reassured and counseled regarding these normal changes of pregnancy. She may have to modify her exercise regimen accordingly. There is no need to refer this patient to a cardiologist or to order an ECG. Systolic ejection murmurs are common findings in pregnant women and are caused by the normal increased blood flow across the aortic and pulmonic valves. The incidence of PE in pregnancy is about 1 in 6400, and in many of these cases there is clinical evidence of a DVT. The most common symptoms of a PE are dyspnea, chest pain, apprehension, cough, hemoptysis, and tachycardia.