Methods And Metrics To Characterize Body Surface Activation In Cardiac Resynchronization Therapy Patients

Abstract

Cardiac resynchronization therapy (CRT) is intended to ameliorate intra- and interventricular electrical dyssynchrony and improve systolic function in heart failure patients. In spite of the success of CRT in many multicenter studies, 30% of CRT patients fail to respond to the therapy. Lack of CRT patient response is linked to the limited sensitivity and spatial resolution of the 12-lead ECG, the current clinical standard for evaluating CRT candidates and patients. A promising alternative to the 12-lead ECG is body surface activation mapping using multichannel electrocardiograms (MECGs). However, in order to be a viable solution to CRT non-response, body surface activation metrics must be not only better correlated with patient CRT outcomes than current 12-lead ECG measures but also readily measurable in a real-time clinical setting. This thesis evaluated an investigational body surface mapping system against these criteria (1) by developing automated QRS complex analysis algorithms for MECGs, (2) by evaluating the reproducibility of body surface activation metrics, and (3) by developing new metrics to predict patient CRT outcomes. This work also explored the use of body surface activation maps to characterize electrical sequences in CRT patients and evaluated the effects of patient geometry on the predictive value of body surface activation metrics.