Modeling an Activation of Heart Ventricular Segments

Background: Here, we present a 2D activation model evaluating the activation of specific myocardium segments (MS). Activation times of specific MS can help to identify conduction disturbances which may result in more targeted treatment of patients.Methods: 12-lead ECG signal was measured with a 5kHz sampling frequency. A total of 10 left bundle branch block (LBBB) and 5 right bundle branch block (RBBB) recordings were analyzed. The analysis includes the following steps: 1) QRS complexes detection and morphology clustering, 2) averaging of 150-1000 Hz envelopes of QRS complexes with dominant morphology, 3) a genetic algorithm (GA) produces artificial envelopes from (initially random) timing of MS activation. The task for GA is to produce envelopes the most similar to measured; then final timing reflects real activation of MS.Results: Presented model determined activation of left ventricular (LV) segments before right ventricular (RV) segments in all RBBB patients (mean 61.4 ± 13.7 ms) and activation of RV segments before the LV segments in all LBBB patients (mean 87.8 ± 15.8 ms). Computed activation of MS corresponds to the expected activation.Conclusion: We introduced a new method determining activation times of MS; this is achieved non-invasively using only ultra-high-frequency precordial ECG signal.