Detection of the valvular split within the second heart sound using the reassigned smoothed pseudo Wigner–Ville distribution

BACKGROUND: In this paper, we developed a novel algorithm to detect the valvular split between the aortic and pulmonary components in the second heart sound which is a valuable medical information. METHODS: The algorithm is based on the Reassigned smoothed pseudo Wigner-Ville distribution which is a modified time-frequency distribution of the Wigner-Ville distribution. A preprocessing amplitude recovery procedure is carried out on the analysed heart sound to improve the readability of the time-frequency representation. The simulated S2 heart sounds were generated by an overlapping frequency modulated chirp-based model at different valvular split durations. RESULTS: Simulated and real heart sounds are processed to highlight the performance of the proposed approach. The algorithm is also validated on real heart sounds of the LGB-IRCM (Laboratoire de Génie biomédical-Institut de recherches cliniques de Montréal) cardiac valve database. The A2-P2 valvular split is accurately detected by processing the obtained RSPWVD representations for both simulated and real data.