Assessment of signal quality and electrode placement in ECGs using a reconstruction matrix

We estimate that as much as 5% of all recorded ECGs worldwide may, to some degree, suffer from poor signal quality or incorrect electrode positioning, which often interferes with correct interpretation of the ECG. Proper training of ECG technicians and regular inspection of signal quality is necessary to achieve a high standard. Due to the large amounts of ECGs recorded daily, we devised an automatic ECG quality inspection method based on the conversion of an ECG into a VCG and back again into a reconstructed ECG. Incorrectly placed electrodes as well as different types of noise can be detected with a high level of accuracy. We used this method to assess the quality of the ECGs in the learning set of the Physionet/Computing in Cardiology Challenge 2011, giving a correct interpretation of the quality of the ECGs of 92.2% which corresponded to a sensitivity of 97.0 and a specificity of 75.1%.