Abstract:

BACKGROUND: In various dangerous layering techniques, baroreflex sensitivity (BRS) is a reliable, accurate, independent predictor for arrhythmia and sudden cardiac death following acute myocardial infarction. Studies commonly utilize pressure and electrocardiogram measurements apparatus to calculate data for BRS.
OBJECTIVE: To design and develop BRS monitor system to predict sudden cardiac death reliably and accurately after acute myocardial infarction.
METHODS: The developed BRS monitor system was used to acquire all patients’ original pulse wave data using electronic blood pressure monitor which also was self-designed. The electronic blood pressure monitor was accomplished by oscillometric method. Pulse wave signals underwent processes of filtering of hardware and software and magnifying for calculating systolic pressure and diastolic pressure. Subsequently, the heart rate was conversed according to the blood pressure value and finally BRS value was calculated by both average values of blood pressure and heart rate. The blood pressure of the subjects was forcibly changed by intravenous injection of vasoactive substances. 
RESULTS AND CONCLUSION: Self-designed BRS monitor system consists of the circuit of the electronic blood pressure monitor, pulse wave processing procedures and BRS calculation program. First, electronic blood pressure monitor was used to get pulse wave data. Then, we wrote computer program that was used to process pulse wave to acquire two groups of data of the blood pressure and heart rate. Afterwards, BRS value was calculated with changing average values of the heart rate and blood pressure. In conclusion, depending on BRS value, we can predict possibility of occurring sudden cardiac death who suffered from acute myocardial infarction. Because the device acquires original data which is used to calculate BRS value only from electronic blood pressure monitor, it is convenient to take. Therefore it is possible to visit patients of acute myocardial infarction at any moment. The development of this monitoring system may provide a better idea to effectively control occurrence of sudden cardiac death after acute myocardial infarction in clinic.