[Abnormalities in the ventricular configuration and movement of the interventricular septum]

We discussed the left ventricular deformity in atrial septal defect (ASD) using two-dimensional echocardiography and elucidated the mechanism responsible for the production of mitral valve prolapse (MVP) associated with ASD. Two-dimensional echocardiography was performed for 78 cases with ASD, ranging in age from three to 64 years. The diagnosis was made by cardiac catheterization in all patients and was verified by surgical intervention in 66 cases. Two-dimensional images were obtained using an electronic sector scanning system of Toshiba (SSH-11A). The recording was made with 8 mm cinematography and an ordinary 35 mm camera. The major diameter/the minor diameter of the short-axis cross-section of the left ventricle was defined as the left ventricular distortion ratio (LVDR). The LVDR in early diastole was significantly larger than those in end-diastole and end-systole (p less than 0.001, n = 33). Furthermore, in end-diastole, the left ventricle showed a greater distortion ratio than that in end-systole (p less than 0.001, n = 33). The left ventricular short-axis area (LVSAA) corrected for the body surface area (BSA) was significantly greater both in early diastole and end-diastole than that in end-systole (p less than 0.001, n = 33). In early diastole, there was a poor correlation between the LVDR and the pulmonic to systemic flow ratio (Qp/Qs) (r = 0.44, p less than 0.05, n = 33). Similarly, the LVDR was poorly related with the right ventricular dimension (RVD) in early diastole (r = 0.43, p less than 0.05, n = 30).(ABSTRACT TRUNCATED AT 250 WORDS)