Design Of ECG Signal Detection And Blood Pressure Measurement System

Electrocardiosignal(ECG) and blood pressure are important physiological signals for human body, they can reflect a lot of health information. Soit is necessary to detect the two kinds of signals. Hypertension is the precursor of cardiovascular disease and its complications. Coronary heart disease(CHD) is a kind of common cardiovascular disease. Acute myocardial infarction(AMI) is the one of the types of clinical manifestations, which is a common disease in clinical. Clinical data indicates that blood pressure and coronary heart disease mortality has a direct relationship and that mortality rate of patients suffering from hypertension and myocardial infarction is higher than the onset of myocardial infarction without hypertension. As a result, it is very necessary to monitor both ECG Signal and blood pressure values for patients with cardiovascular disease and myocardial infarction. Based on the above issues, the measurement of the timely changes of ECG and blood pressure are combined together in our research to provide an important diagnosis and treatment basis for the disease related to both ECG and blood pressure.In this paper, a measurement system was designed to monitor blood pressure and ECG simultaneously. It comprises blood pressure measure modules and ECG detect module. ECG signal detect module realizes 18 leads ECG detection to comprehensive monitoring the heart. ECG data acquisition circuits collect the signal by using multiple ADAS1000 chip with cascade structure.. The blood pressure measure module adopts oscillography method, which is the most mature and widely used. The signal obtained from pressure sensor via filtered、amplified and other post-processing, then sent to the microcontroller for data acquisition and convert. ECG signal detect module and the blood pressure measure module are controlled by the same microcontroller to realize synchronous acquisition of blood pressure and ECG signals. Collected data can also be transmitted to principal computer for data filtering and calculationby serialinterface.Thus the the heart rate 、 blood pressure and signal waveform are finally showed. By setting the normal range of blood pressure values, the system will give an alarm to prompt the user to view the ECG in a timely manner when blood pressure abnormal changes occur and it is out of the range.The results showed that this monitoring system can effectively collect ECG and blood pressure signals, calculate blood pressure values and heart rate, and display the results and ECG waveform. Systolic blood pressure range achieves 45-260 mm Hg.Diastolic blood pressure range achieves 45-260 mm Hg.The average pressure range achieves 45-260 mm Hg. Blood pressure measurement accuracy achieves ± 4mm Hg.Relative error of average heart rate is less than 8%. At the same time, blood pressure measurement meets the recommended standard deviation of no more than 8mm Hg proposed by United States Association for Advancement of Medical Instrumentation(AAMI).The measurement system achieves a joint monitoring of ECG and blood pressure, which provided an assistance of the analysis and diagnosis of heart diseases on blood pressure and electrocardiosignal.