Analysis of the spatial resolution of body-surface dominant-frequency mapping systems

In this study we assess the ability of high-density body-surface lead systems to resolve local dominant-frequency (DF) values. In a detailed numerical model of the human thorax, we calculate the measurement sensitivity distribution (MSD) of the 117 unipolar leads of a Dalhousie lead system. Based on the MSD, we compute the lead equivalent volume (LEV) of each unipolar lead and use it to quantify the lead spatial resolution (SR). Anterior leads positioned in columns 4-6 and rows 3-5 of the Dalhousie system have the lowest LEV values (2.4% <; LEV <; 7%) and concentrate their sensitivity mostly in the right myocardium. Higher LEV values are achieved at posterior locations (LEV >; 11%). Optimal lead positioning can increase the resolution of local DF values. However, the ability to resolve local DF values in selected regions is limited by the intrinsic MSD of body-surface leads. Our results indicate that further signal processing stages are needed to improve the SR of body-surface DF maps.