Desenvolvimento de um sistema de monitoramento cardíaco

Abstract

The doctor-patient relationship is often distant due to the difficulties of attendance, long waiting time in hospitals and distance from large centers. For this reason, mobile technology (mHealth) is seen as a great ally for disease treatment and cost reduction, where through the applications of mobile devices, sensors and portable measuring devices, it reduces the distance and optimizes treatment between doctor and the patient. This work has the purpose of developing a device that has the ability to capture cardiac signals for monitoring purposes in order to offer comfort and agility to the patient. The project presents a system of acquisition, conditioning and transmission of cardiac signals using Bluetooth protocol. The acquisition of the signals is performed through three biopotential electrodes, followed by a pre-amplification and filtering stage, consisting of an instrumentation amplifier, a high pass analog filter, a low pass filter and a bandstop filter that has the purpose of eliminate noise and limit study only to the frequency of interest. The signal passes through an offset circuit and an adder circuit to be limited between the ranges accepted by the microcontroller for acquisition. Digital processing is performed by the Arduino MEGA2560 microcontroller, where the analogue / digital conversion of the signal is performed. The signal is sent via Bluetooth via the module HC-06 and then transmitted to the receiving station, in the case of this work, a laptop computer. Simulations and tests were carried out at all stages of circuit development. However, the analog signal conditioning circuit did not show electrocardiogram signals morphologically similar to the originals. To obtain the signal according to the ones found in the bibliography, digital filtering techniques implemented through mathematical simulations software were used. The final result is within the expected for the operation of the circuit.