Left Ventricular Function of Mitral Stenosis in Early

Postoperative Period - Evaluation of Left Ventricular Function with Left Ventricular Function Curve

Abstract

1. For the purpose of evaluation of the left ventricu lar function of mitral stenosis in early postoperative period, the left ventricular function of 29 patients (18 cases of pure mitral stenosis (MS),3 cases of MS+ aortic regurgitation (AR), and 8 cases of atrial septal defect (A SD))were evaluated in early postoperative period (6-35 hours after operation) comparing with those of preoperative and late postoperative period (3-8 weeks after operation)
2. In control group (ASD), cardiac index (CI), stroke inde x (SI) and stroke work index (SWI) did not remarkably change, although pulmonary arterial pressure (PAP) and pulm onary arterial resistance (PAR) were decreased in early postoperative period. The arterial pressure (AP) and heart rate (HR) did not show signifcant change.
3. The patients of pure MS were divided in 4 grou ps accordingt o PAP and cardiac rhythmus. In group I, PAP was bellow 25 mmHg with sinus rhythmus, in group II, PAP was bellow 25 mmHg with atrial fibrillation, in group III, PAP was higher than 25 mmHg with sinus rhythmus, in group IV, PAP was higher than 25mmHg with atrial fibrillation. In group I and II, CI, SI, and SWI were remarkably decresed during early postoperative period, but in group III and IV, they were unchangable or little improved in this period. However, in late postoperative period, CI, SI and SWI were improved significantly as compared with those of preoperative period in all four groups.
4. PAP of group III and IV with pulmonary hypertension, fell in early postoperative period. However, in group III, PAP increased again after the short duration of decreased pressure. The decrease of PAP in group I and II was little demonstrated. PAR was tended to increase in early postoperative period in all groups. Particularly, in group III, PAR rose remarkablly, however, in all groups, PAR lowered bellow preoperative value in late postoperative period
5. The right atrial pressure (RAP) was tended to increase in early postoperative period, but the left atrial pressure (LAP) fell in all groups, especially in group III and group IV. The LAP and RAP in MS group were higher than those of ASD group in early postoperative period and the correlation of LAP and RAP in MS group was poor. The estimation of LAP from RAP in early postoperative period of MS group was difficult.
6. The left ventricular function curves with volu me overloading in control group (ASD)located in left upper quadrant but those in MS group located in right lower quadrant in early postoperative period. Particularly the left ventricular function curves of group I located more left upper portion than other groups, and that of group IV located rather right lower portion than other groups. The slopes of left ventricular function curves were gentle except that of group I, which revealed the depletion of left ventricular performance.
7. The value of CI obtained by means of volume load, in early postoperative period (6 hrs after operation) had good correration to the value of CI at rest in late postoperative period.
8. The evaluation of left ventricular function curves obtained in early postoperati ve period was usefull for the postoperative patient management.