ECG/Electrocardiogram Machine

Project Description

An ECG/EKG is the medical instrument that can measure the heart activity and convert it into an analog signal which can be recorded on paper or digitized on an LCD screen. ECG and EKG are synonymous and used interchangeably, it is short for “electrocardiogram” or “electrokardiogram” which was the original term used by its inventor, Willem Einthoven. An ECG machine can be used to detect abnormal rhythms caused by damage to the conductive tissue or electrolyte imbalances or it can identify damaged heart muscle in specific areas. ECGs work by detecting and amplifying the tiny voltage changes on the skin that are caused when the electrical signal in the heart muscle is charged and spread during each heartbeat. The signal recorded as the difference between two potentials on the body surface is called an “ECG lead”. Each lead is said to look at the heart from a different angle. Typically ECGs have 3 leads but some can have upwards of 12 leads. Once the signal is amplified and filtered, it gets passed into an ADC so it can be sampled and displayed on an LCD screen using a microprocessor.

Our ECG is small, low cost, and portable. We decided to construct a single lead ECG system primarily used for basic heart monitoring, our device is purely for educational purposes and should not be mistaken for a credible medical device for diagnosing actual heart problems. The reason that we constructed a single lead ECG and not three lead is because one lead is sufficient enough to detect basic heart arrhythmias, which can be future improvement to our current prototype. One-lead ECGs can also be used to accomplish 3-lead recordings if measured sequentially. We also implemented some safety features such as lead-off detection for electrodes and ESD protection. We developed an Android application that runs on multiple Android devices. With the application, the mobile device serves as the ECG display for our ECG reader. The cost of producing this prototype is shared among our team members.