10th March 2024

A 56-year-old male has been referred from his GP with vague symptoms of exertional dyspnoea and fatigue.

A 56-year-old male has been referred from his GP with vague symptoms of exertional dyspnoea and fatigue. He has a white-collar job, is a smoker, and has a BMI of 37 kg/m2. He has no pertinent past medical or family history. The GP arranged an echo that showed no ventricular failure but a PASP of 50 mmHg and a chest X-ray that was normal. On review, he has no clinical signs except for a blood pressure of 180/78 mmHg. What test would most likely identify the underlying cause for the raised pulmonary pressures?

Select the SINGLE most appropriate option from the list below. Select ONE option only.