Abstract
Sequential changes of left ventricular function after cardiac surgery were studied in 53 patients using echocardiography. Surgery for coronary artery bypass grafting (CABG) was performed on 14, mitral valve replacement to mitral stenosis (MS) on 14, to mitral regurgitation (MR) on 9, direct closure of atrial septal defects (ASD) on 6, and double valve replacement (DVR) on 10. The results of this study were as follows. 1) CABG: Ejection fraction (EF), fractional shortening (FS) and stroke volume index (SVI) decreased early postoperatively, and recovered after three months. However, mean velocity of circumferential fiber shortening (mVcf) decreased during three to six months, and recoverd after one year. 2) MS: MVcf increased early postoperatively, but indicated no significant improvement after six months. SVI and cardiac index (CI) improved after one year. 3) MR : Postoperatively, end-diastolic dimension index (EDDI) and SVI decreased significantly. Changes of EF were not significant, but tended to improve after one year. 4) ASD: EDDI, SVI and CI increased two weeks after surgery, and no significant changes were noticed in EF, FS and mVcf. 5) DVR: EF and FS increased one year after surgery. From the these results, the functions of the left ventricle were changed significantly by postoperative therapy during the early postoperative period. Therefore, we conclude that improvement of left ventricular function should be assessed two weeks after cardiac surgery in ASD, six months in CABG and MS, and at one year in MR and DVR.
