Abstract
The electrocardiogram (ECG) is a non-invasive diagnostic tool that records the heart's electrical activity to detect and diagnose cardiac conditions. The 12-lead ECG remains the gold standard for initial evaluation due to its comprehensive waveform analysis. However, its bulkiness, need for precise electrode placement by trained personnel, and limitations for continuous or ambulatory monitoring render it impractical for routine use outside clinical environments. Portable and wearable ECG devices have emerged as viable alternatives, enabling accessible, real-time cardiac assessment in diverse settings. This study presents the design of a lightweight, wearable five-lead ECG device for non-invasive cardiac monitoring, featuring high-resolution signal acquisition and built-in protections against electrical interference to deliver clear, low-noise waveforms. In addition to a rechargeable battery for extended daily use and wireless Bluetooth transmission for seamless data sharing with clinicians, the device incorporates an onboard accelerometer that detects motion, posture, and sleep state to dynamically adjust filtering and further reduce motion noise. The work includes a schematic illustrating circuit integration and functionality, simulations demonstrating the filters' effectiveness in attenuating unwanted signals from the electrodes, and a complete three-dimensional model of the printed circuit board with its enclosure. The proposed design demonstrates a feasible and efficient approach to compact, wearable ECG monitoring. By integrating an accelerometer for adaptive filtering, the system reduces motion noise and improves waveform reliability during daily activities. These findings support its potential use in continuous cardiac assessment outside clinical environments.