PROGNOSTIC IMPLICATIONS OF PLASMA-LEVELS OF ATRIAL-NATRIURETIC-FACTOR IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION

Several neurohormonal factors have been proposed as markers of the severity of acute myocardial infarction (MI). To determine whether plasma concentrations of atrial natriuretic factor (ANF) might predict post-MI prognosis, we studied 130 patients with acute MI (97 males and 33 females, mean age 62 years). Within one-half to one day after admission, a blood sample was taken for estimation of circulating ANF. The mean follow-up period was 37 months, and the follow-up rate was 97%. Of the 130 patients, 28 died from cardiac causes during the follow-up period. Patients were classified into three groups according to plasma ANF levels (group 1, < 99 pg/ml; group 2, 100-199 pg/ml; group 3 > 200 pg/ml). The survival curves were constructed by the Kaplan-Meier method. There were significant differences in the cumulative survival rate among the three groups (group 1 > group 2 > group 3; p < 0.001). The baseline characteristics (age, atrial pressure, and cardiac index) were different among the groups, therefore these variables were analyzed by a Cox multiple regression model. Significant predictors of cardiac mortality were plasma ANF class (p < 0.002) and pulmonary capillary wedge pressure (p < 0.007). In conclusion, these observations demonstrated that stratification of acute MI patients by plasma ANF level is a useful non-invasive method for predicting prognosis and for identifying individuals at high risk of cardiac death.