Heart rate estimation and validation algorithm for fetal phonocardiography
Objective. Fetal heart rate (FHR) is an important parameter for assessing fetal well-being and is
usually measured by doppler ultrasound. Fetal phonocardiography can provide non-invasive,
easy-to-use and passive alternative for fetal monitoring method if reliable FHR measurements can be
made even in noisy clinical environments. Therefore, this work presents an automatic algorithm to
determine FHR from the fetal heart sound recordings in a noisy clinical environment. Approach. Using
an electronic stethoscope fetal heart sounds were recorded from the expecting mother's abdomen,
during weeks 30 –40 of their pregnancy. Of these, 60 recordings were analyzed manually by two
observers to obtain reference heart rate measurement. An algorithm was developed to determine FHR
using envelope detection and autocorrelation of the signals. Algorithm performance was improved by
implementing peak validation algorithm utilizing knowledge of valid FHR from prior windows and power
spectral density function. The improvements in accuracy and reliability of algorithm were measured
by mean absolute error (MAE) and positive percent agreement. Main results. By including the
validation step, the MAE reduced from 11.50 to 7.54 beats per minute and positive percent agreement
improved from 81% to 87%. Significance. We classified the recordings into good, moderate and poor
quality to understand how the algorithm works in each of the case. The proposed algorithms provide
good accuracy overal...
Source: Physiological Measurement - Category: Physiology Authors: Amrutha Bhaskaran, Sidhesh Kumar J, Shirley George and Manish Arora Source Type: research