Right ventricular function in cardiovascular disease evaluated by magnetic resonance imaging

Right ventricular wall thickness, wall motion, and areas of the right ventricular cavities were measured using ECG-gated magnetic resonance imaging (MRI) in 46 patients with cardiac diseases, comparising atrial septal defect (ASD, n=6), hypertrophic cardiomyopathy (HCM, n=19), dilated cardiomyopathy (DCM, n=8), and old myocardial infarction (OMI, n=13). Seven normal volunteers were examined as controls. Transverse images at the level of the tricuspid valve were obtained for measurement. A mean value and standard deviation of the anterior wall thickness of the right ventricle and the area index of the right ventricular cavity at end-diastole were 3.4±0.7 mm and 10.6±1 cm2/m2, respectively, in the control group. The anterior and lateral walls and tricuspid annulus moved inward to the right ventricular cavity in systole. The excursion of the lateral wall and tricuspid annulus was larger than those of the anterior wall. The interventricular septum (IVS), however, moved outward to the left ventricle in systole. The thickness of the right ventricular anterior wall was 5.8±1.4 mm larger in the HCM group that in the control group. The area index of the right ventricular cavity was larger in the ASD group (18.4±5.4 cm2/m2) and smaller in the HCM group (9.1±1.6 cm2/m2) than the control group. The IVS moved inward in all of the ASD patients and in some of the HCM patients. The anterior and lateral wall motion was decreased in the ASD and DCM groups. (Namekawa, K)