11/02/2009

Fraunhofer-Institut für Photonische Mikrosysteme IPMS

Immediate Evaluation of ECG and Movement Signals

ECG vital - a portable ECG instrument
At present, the evaluation of long-term ECGs is performed by the attending physician, who enters the ECG data into a PC where it undergoes a preliminary analysis in a software programme following a patient’s visit to the practice. The physician looks at the flagged critical areas and makes a diagnosis. For years IPMS has been researching a suitable algorithm, which will make an analysis directly within ECG recorder possible. The goal is to provide a comprehensive evaluation of the current cardiac function. For this purpose, diverse methods are employed, such as rhythm analysis, QRS classification, analysis of the atrium activity, as well as QT measurement. For example, this software has been integrated into the portable instrument “ECG-vital” from Fraunhofer IPMS. When the analysis software detects a change in the ECG, the recorder immediately sends an excerpt of the ECG through a gateway to the physician, who can then make a decision regarding follow-up. This way, long-term evaluation can be performed without the patient having to go to the doctor’s repeatedly. Parallel to the ECG recording, the patient’s movements and physical activity is also recorded and analysed: The instrument automatically recognises whether the patient is standing, lying down, walking, running, or climbing stairs. This means that an ECG recording can be performed under real everyday conditions, without the patient having to keep a diary of his daily activities. Due to the link between the physical activity data and the ECG data, an improvement in the analysis results is achieved. In particular, changes occurring in the ECG can be correlated to the corresponding physical stress situations, and disturbances caused by movement artefacts can be effectively reduced. If the patient is climbing stairs, for example, and the heart rate increases, then pathological tachycardia will not be mistakenly identified, as an increase is normal under such stress conditions.