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Published on: February 7, 2014
A novel parameter derived from photoplethysmographic pulse wave to distinguish preeclampsia from non-preeclampsia
Hang Chen1, Feng Jiang1, Dan Drzymalski2
1College of Biomedical Engineering and Instrument Science, Zhejiang University, China; Key Lab of Biomedical Engineering of Ministry of Education, Zhejiang University, China; Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, China.
Objective:
To describe the comparative hierarchical area ratio (CHAR), a novel parameter derived from the photoplethysmographic (PPG) pulse wave and differences in CHAR values in parturients with and without preeclampsia (PE).
Methods:
A total of 59 parturients (37 without and 22 with PE) was conducted at the Women's Hospital, Zhejiang University, School of Medicine in Hangzhou, China. We calculated the CHAR values derived from the PPG pulse wave and compared them in parturients with and without PE.
Result:
The values of CHAR derived from the parturients with PE were lower compared to those without PE (p < 0.01). The ROC analysis indicated that the best threshold for the mean value of CHAR was 7.92 to predict PE with a sensitivity of 86.4% and a specificity of 87.1%, while the threshold for the standard deviation of CHAR was 0.76 with a sensitivity of 77.3% and a specificity of 77.4%. The area under the curve (AUC) was 0.91 for mean value of CHAR while 0.78 for standard deviation of CHAR. Meanwhile, a contrast of AUC between CHAR and the former parameter we proposed showed CHAR had better performance in distinguishing PE (0.908 over 0.615, p < 0.01).
Conclusion:
The novel parameter, CHAR, derived from PPG pulse wave differs in parturients with and without PE with high sensitivity and specificity, suggesting that the CHAR might be an effective tool in differentiating the presence of PE.
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