Instantaneous respiratory rate estimation from multilead ECG delineation using VCG directions on fiducial points

The main purpose of this work is the estimation of the respiratory rate (γrR) from the electrocardiogram (ECG). In this study, the tr was estimated from the same Fit directions of maximum projection (FD) used for multi lead ECG automatic delineation (ML). A previously developed and validated methodology for boundaries location was extended to include wave peaks and estimate FD. The median of power spectral density obtained over the directions based on QRS complex main peak, T wave peak and end spatial loops was used for tr estimation. In a control database, the proposed method yielded more accurate tr estimates (mean absolute error (MAE), 2.64 bpm, SD=3.92)than the estimates based on the single-lead ECG R-peak amplitude (MAE values from 3.29 to 5.26 bpm, SD > 5) and RR series (2.89 to 3.66 bpm, SD >4.6), close to results from EDR method (2.89 bpm, SD=3.63).