Region of interest sensitivity ratio in analyzing sensitivity distributions of electrocardiographic measurements

Modern devices such as wearable and implantable systems provide new methods for bioelectric measurement while creating new needs to assess the efficacy of the measurements. A modeling related analysis method, called the region of interest sensitivity ratio (ROISR), has been developed and applied hitherto in analyzing EEG measurements. ROISR describes how well the sensitivity of a measurement is concentrated within the region of interest (ROI). The objectives of the present study were to demonstrate and evaluate the applicability of this method in analyzing the specificity of ECG leads and to compare the results with those previously published. Here the specificities of the 117 leads of a Dalhousie body surface ECG mapping system to different segments of the left ventricular myocardium and the whole right ventricular free wall were analyzed. The ROISR method was also validated with epicardial dipole simulations. The results are consistent with those from previous clinical studies, and the ROISR method is thus applicable in future studies where, e.g., sensitivity distributions of implantable ECG measurements are analyzed.