1986 Volume 23 Issue 6 Pages 565-572
This study was performed to investigate the hemodynamic profile and the prognostic value of hemodynamic parameters in the aged with acute myocardial infarction (AMI). One hundred patients, admitted to CCU within 72 hours from the onset of AMI, were studied. These patients were divided into an older group (61 patients over 60 years) and a younger group (39 patients under 60 years). The initial hemodynamic parameters, measured with a Swan-Ganz triple lumen catheter, were compared between these two groups. An attempt was made through discriminant analysis using hemodynamic parameters to classify early deaths (within 30 days) and survivors (beyond 30 days) in the older group. The early mortality rate in the older group 26.2% as compared to 7.6% in the younger group. In the older group, the rate was 32.3% for patients over 70 years and 18.5% for patients in their sixties. Regarding hemodynamic profile, the older group, when compared with the younger, showed a significant decrease in mean arterial blood pressure (MBP), cardiac index (CI), left ventricular stroke work index (LVSWI) and slope of right ventricular function curve, but showed a significant increase in heart rate (HR) and total peripheral resistance index. In the patients of the older group who suffered from early death, MBP, CI and LVSWI were significantly lower, while HR and pulmonary arterial end-diastolic pressure (PAEDP) were significantly higher than the survivors of the same group. The discriminant function using initial hemodynamic parameters was derived as followed: z=-0.00219+(SBP×0.00133)+(DBP×0.00195)+(-MBP×0.00154)+(-PASP×0.0038)+(-RAP×0.00019)+(PAEDP×0.002)+(HR×0.00125)+(-CI×0.01446)+(LVSWI×0.00087)+(-RVSWI×0.00165), where SBP is systolic blood pressure, and DBP diastolic blood pressure, PASP pulmonary arterial systolic pressure, and RVSWI right ventricular stroke work index. Mahalanobis' generalized distance was 5.30413 and F value was 4.24449 (p<0.05). The calssification error rate of this function was subsequently applied to 19 elderly cases. The results suggested that the aged with AMI had a high mortality rate and showed depressed biventricular performance. The multivariate analysis using hemodynamic parameters might be clinically useful in predicting the prognosis of the acute phase of myocardial infarction in the aged.