An Artificial Arm Pressure Able to Reproduce Oscillometric Blood Pressure for Testing Holter Devices

The aim of this work is the realization of an "Artificial Arm Pressure" permitting to reproduce oscillometric waveforms able to replace expensive clinical trials for validating and testing a Holter blood pressure device. To perform this new device a hybrid simulator (numerical/hydraulic) of the left cardiocirculatory network was implemented in order to reproduce in different fixed times different oscillometric blood arterial pressure waveforms. The "Artificial Arm Pressure" consists of a numerical simulator of the left cardiovascular system, in which it is possible to fix the left atrial pressure (preload) and the left arterial pressure (afterload) and of an hydraulic system consisting of a D/A converter, a servoamplifier, a D/C motor and a "gear pump". The numerical simulator allows to vary the heart rate, the time duration of systole/diastole and the morphology of the ventricular/aortic pressure waveform in order to reproduce different physiopathology cardiovascular diseases. The hybrid simulator can be used to program the type and amount of steps you want to perform in 24/48-h to check the correct operation/calibration of the Holter blood pressure device. A Holter programmed to acquire data every 15 min has been tested for 24-h on the "Artificial Arm Pressure". The comparison between simulated and measured data shown that for systolic (diastolic) blood pressure the percentage of variation was in average about ±2.6% (±2.9). In the case of HR, the percentage of variation was in average about ±2.0%.