Published June 7, 2026 © MIT

A low-cost, ultra-reliable Holter ECG monitor

This project combines the robustness of the Ada programming language for embedded cardiac signal processing with the simplicity of MIT App.

IntermediateProtipOver 2 days5

A low-cost, ultra-reliable Holter ECG monitor

Things used in this project

Hardware components

Arduino Nano R3

An AVR microcontroller (ATmega328P) runs firmware written in Ada. The program handles analog-to-digital conversion and precise data packaging

SparkFun Single Lead Heart Rate Monitor - AD8232

Biometric signals are captured using a dedicated analog sensor which handles the initial filtering

HC-05 Bluetooth Module

Wireless Transmission: Formatted data is sent via the UART interface to a standard Bluetooth module (HC-05), taking into account its processing times to ensure a continuous, bottleneck-free data stream

Software apps and online services

MIT App Inventor

A custom Android app, developed quickly using MIT App Inventor, receives Bluetooth packets, decodes them, and displays the electrocardiogram in real time on the smartphone screen.

Microsoft VS Code

Story

Continuous cardiac monitoring (Holter monitoring) is crucial for diagnosing arrhythmias and other cardiovascular conditions. However, in the African context, traditional medical equipment is often very expensive and inaccessible to many healthcare facilities or for educational purposes. There is a real need for low-cost diagnostic solutions capable of running on standard hardware without compromising system stability.