PEP and LVET Detection from PCG and ECG

The systolic time intervals of hearts are related to health. People with myocardial dysfunction will have a longer pre-ejection period (PEP) and a shorter left ventricle ejection time (LVET) than healthy people. The purpose of this paper is intended to detect PEP and LVET accurately from electrocardiography (ECG) and phonocardiogram (PCG). Generally, there are several kinds of noises from environment or breathing in PCG. It is necessary but difficult to extract the best signals we want. Our approach is to use a simple DSP-based method in PCG to detect aortic valve opening (AVO) and aortic valve closure (AVC) times as well as R-peak time in ECG. Then, the PEP and LVET can be calculated. We evaluated PEP and LVET of 72 files from 46 people. To the annotated data, the PEP range is around 5 ms to 100 ms; the LVET range is around 170 ms to 380 ms. Our PEP results have 63.96% accuracy within 20 ms absolute error and 91.74% accuracy within 40 ms absolute error; LVET have 75.48% accuracy within 40 ms absolute error and 93.53% accuracy within 80 ms absolute error.