# file: gqrs.conf G. Moody 18 October 2007 # # Configuration file for `gqrs' and `gqpost' applications # To use this file, use the -c option of gqrs and gqpost: # gqrs -c gqrs.conf ... # gqpost -c gqrs.conf ... # This file contains parameter definitions, which can be provided in any of # the following forms: # parameter = value # parameter: value # parameter value # Neither parameter names nor values may contain embedded whitespace. # The order of parameter definitions in this file is not significant, except # that a later definition overrides any earlier definition of the same # parameter. Two or more parameter definitions may appear on a single line if # separated by whitespace. Empty lines, and lines beginning with `#', are # ignored. # The parameter values given below have been chosen for use with adult human # ECGs. In general, pediatric and small animal ECGs have more rapid heart # rates, and QRS complexes that are shorter and lower in amplitude. HR 75 # Typical heart rate, in beats per minute # RR 0.8 # Typical inter-beat interval, in seconds # Note that HR overrides RR if both are set -- in this case, RR = 60/HR RRdelta 0.2 # Typical difference between successive RR intervals in seconds RRmin 0.28 # Minimum RR interval ("refractory period"), in seconds RRmax 2.4 # Maximum RR interval, in seconds; thresholds will be adjusted # if no peaks are detected within this interval QS 0.07 # Typical QRS duration, in seconds QT 0.35 # Typical QT interval, in seconds RTmin 0.25 # Minimum interval between R and T peaks, in seconds RTmax 0.33 # Maximum interval between R and T peaks, in seconds QRSa 750 # Typical QRS peak-to-peak amplitude, in microvolts QRSamin 130 # Minimum QRS peak-to-peak amplitude, in microvolts (* see note) # For infants, these settings may yield better results than the defaults for # adults given above: # HR 120 # QS 0.05 # QRSa 500 # Settings for other animals # By choosing appropriate values for HR, QS, and QRSa, gqrs and gqpost can be # used to analyze ECGs from a wide variety of animals. In general, gqrs and # gqpost can adapt as needed if these parameters are within a factor of 2 of # their ideal values. # For mammals, the typical heart rate is about 240 bpm, divided by the fourth # root of the body mass in kilograms: # HR ~= 240 bpm / (M^(1/4)) # (Schmidt-Nielsen K. Animal Physiology: Adaptation and Environment. Cambridge # University Press, 1997). # The typical QRS duration is proportional to the cube root of the mass of # the heart, although there is evidence that for the largest mammals (elephants # and whales), the normal QRS duration does not exceed 200 ms, suggesting that # the His-Purkinjie system may be denser in these species (Meijler et al., # JACC 1992(Aug):475-479). # QRS amplitudes vary considerably depending on electrode type and location; # set QRSa to match the typical peak-to-peak amplitude for your recordings. # The other settings (RR, RRdelta, RRmin, RRmax, QT, RTmax, and QRSamin) may be # set to zero, in which case gqrs and gqpost determine reasonable values for # them as needed from HR, QS, and QRSa. # * SAFETY NOTE: Applicable standards do not permit ECG monitors intended for # human use to detect QRS complexes with peak-to-peak amplitudes below 150 # microvolts, so QRSamin must not be reduced for human ECG monitoring # applications. This regulatory requirement is intended to prevent adaptive # detectors such as gqrs from triggering on low-amplitude noise during # asystole.