ABSTRACT
Based on the past observation of recording abnormal impedance cardiogram (ICG) in 13% normal subjects and subsequent detection of coronary artery disease (CAD) in majority of these cases, led the authors to record peripheral impedance plethysmograms (IPG) in control subjects and patients using impedance cardiovasograph, developed by electronics division, Bhabha Atomic Research Centre (BARC). Analysis of peripheral plethysmograms, thus recorded, has shown 8 dominant morphological patterns of the peripheral pulses depending upon their status of health. In cognizance of these observations, different methods of pattern analysis were used for pattern identification. Fourier Transform based method has been observed to yield higher diagnostic yield. Morphology index (MI) of the peripheral pulse derived from this method was observed to vary from 0.28 to 1, the former indicating the poorest and later the normal health. Among 100 subjects suffering from various disorders, 8 patients with coronary artery disease have recorded average index to be between 0.30 and 0.45.