An automated electrocardiogram (ECG) detection and annotation algorithm was developed base on the works presented in Martinez et al. , Zusterzeel et al., and Smisek et al. The algorithm was coded in MATLAB and uses the discrete time wavelet transform and multiple layers of segmentation to isolate important components of a raw ECG signal. The results are compared to the Strauss definition of left bundle branch block (LBBB) to produce a diagnosis for a patient.