A 57-year-old woman is referred to the office by her primary care provider for progressive exertional dyspnea during the past 6 months. She reports a near syncopal episode while walking at a brisk pace to catch a taxi. Her medical history is unremarkable, except for several miscarriages.
Her blood pressure is 120/78 mm Hg, her heart rate is 87 bpm, and she has clear lungs on examination. A slight right ventricular lift is noted on examination but her heart sounds are normal except for an unusually loud P2. Two-dimensional echocardiography is done in the office, which shows normal left ventricular function and normal ejection fraction. However, her right ventricle is dilated, with decreased function, and right ventricular systolic pressure is elevated at 57 mm Hg.
She is referred for right heart catheterization, which confirms the suspicion of pulmonary arterial hypertension with a transpulmonary gradient of 40 and a pulmonary vascular resistance of 8 Wood units.
What is the next best test in her workup?
A. Ventilation-perfusion (V/Q) scan
B. Computed tomographic angiography of the pulmonary arteries
C. Cardiac magnetic resonance imaging
D. Chest radiograph
E. Noncontrast chest computed tomography