Obstetrics and Gynaecologymiddle twist
A 29-year-old woman at 28 weeks gestation presents with sudden pleuritic chest pain and breathlessness. Her pulse is 108/min, oxygen saturation is 97% on room air, and there is no leg swelling or tenderness; the chest radiograph is normal. Pulmonary embolism is suspected, but she is haemodynamically stable. Which one of the following is the most appropriate investigation?