Visualization of the Multichannel Seismocardiogram

Kim Munck1, Kasper Sørensen2, Johannes Struijk1, Samuel Emil Schmidt1
1Aalborg University, 2University of Aalborg


Intro: The multichannel seismocardiography (mchSCG) project aims to develop the technology and knowledge-base to understand the distribution of mechanical waves on the chest wall related to the motion of the heart. This study focuses on the development of tools for visualization of those waves. Method: We investigated four visualization methods; SCG chart, color plot, tracking map, and seismic mesh. Signals from the mchSCG were collected in a four by four grid by 16 three-axis accelerometers placed on the chest of 11 healthy males. The visualization methods were validated for their abilities to show temporal, spatial, directional, and small amplitude sensitivity aspects of the signals. Results: The SCG chart shows best temporal and small amplitude sensitivity information, however, it lacks on the spatial and directionality information. Color plots give an improved spatial overview, but with a reduced small amplitude sensitivity and with a low degree of temporal information. Tracking maps are good to demonstrate directionality, but, lacks small amplitude sensitivity. The seismic mesh method is good at showing spatial and directionality information, but with reduced small amplitude sensitivity and temporal information. Both the color plot and seismic mesh require videos or snapshots to include temporal information. Discussion: Dependent on which signal aspects are of interest, the four visualization methods have their specific suited purposes. These visualization methods can assist further investigation of the complex waves on the chest wall caused by the motion of the heart.