The diagnosis of a patient with pulmonary hypertension (PH) requires many investigations. At present cardiac catheterisation is the cornerstone investigation in these patients where it is used to establish disease severity and estimate prognosis. It is an invasive procedure which is expensive and not without risk to the patient. Despite the multitude of tests performed, identifying those patients with PH who have a poor diagnosis can be difficult. The aim of this study is to improve the assessment of patients with PH using novel magnetic resonance techniques.