[Magnetic resonance tomography in pulmonary hypertension]

We examined 23 patients with pulmonary hypertension of varying aetiology by MRI and compared the results with those of right heart catheterisation. The best correlation was obtained between right ventricular mural thickness and mean pulmonary pressure (R = 0.91, p = 0.001). There was significant correlation (R = 0.85, p = 0.001) for the diameter of the inferior vena cava, which was dilated in all patients with pulmonary hypertension. There was no significant correlation between mean pulmonary pressure and the diameters of the superior vena cava or the main pulmonary artery branches (R = 0.55 and 0.75 respectively, p less than 0.05). Amongst functional measurements there was a correlation between right ventricular ejection fraction and mean pulmonary artery pressure (R = 0.71, p = 0.001). There was no correlation between right ventricular end-systolic and end-diastolic volume. In all patients with pulmonary hypertension, dynamic flow sensitive gradient echo sequences showed the presence of tricuspid insufficiency. A further semiquantitative criterion for the presence of pulmonary hypertension in 4 patients (17%) was an abnormal signal from the main pulmonary artery in early to mid-systole shown on T1-weighted transverse sections.