The Value Of Baroreflex Sensitivity To Predict The Early Death Of Acute Myocardial Infarction Patients

Objective To study the change of baroreflex sensitivity (BRS) and the effect of angiotensin coveting enzyme inhibitors (ACEI) on BRS after ST segment elvation myocardial infarction (STEMI) patients, and BRS was investigated to predict the early mortality of STEMI patients.Methods BRS were assessed by bolus phenylephrine techique in 66 STEMI patients and 30 physical examination normal controls. AMI patients were randomly divided into two subgroups, A group patients were treated with ACEI, B group patients were not treated with ACEI.Results BRS of the patients with STEMI was much lower than that of the normal controls (3.9±1.24ms/mmHg vs 11.3 ± 4. 71ms/mmHg, p<0.01);Between group A and B were also significant (3. 4 + 0. 99ms/mmHg vs 3. 9 ± 1. 24ms/mmHg, p<0. 01). 6 patients with STEMI were dead, but the placebo were no death, and the BRS of all dead patients were less than 2. 5ms/mmHg.Conclusion Drepressed BRS after STEMI was considered anindication of decreased vagal and increased sympathetic tone. ACEI appeared to improve BRS and regulate the balance of cardiac automatic nervous system in the early phase of STEMI. It was obviously that BRS<2. 5ms/mmHg could predict the early death rate in STEMI patients , the sensitivity and sepcificity were 100% and 46.2%, and the value of BRS to predict the mortality in the first week after STEMI was equal to that in the fourth week. Therefore, the BRS of STEMI patients in the first week can more early and effectively guide doctors to prevent the death of STEMI patients.