Comparison of the consistency in measurement of central aortic pressure by two non-invasive devices

Objective This study was to compare the consistency in the measurement of central blood pressure ( CBP ) by two non-invasive devices ( Omron-HEM9000AI and SphygmoCor ) . Methods From Aug.2010to Sep. 2010atotal of 43coronary artery disease inpatients [ aged 40-80 ( 60.5±9.4 ) year old ,( male 32 , 74.4% )] were enrolled. The CBPs of each patient were recorded by Omron-HEM9000AI and SphygmoCor respectively. Pearson correlation analysis , paired t-test , and Bland-Altman plot were used to evaluate the correlation and consistency in CBP measurements by two devices. Results Pearson correlation analysis showed that central systolic blood pres-sures ( cSBP ) measured by two devices were positively correlated with the peripheral systolic blood pressures ( r= 0.942and 0.971 , both P0.01 ) . There were positive correlations in cSBP ( r=0.972 , P0.01 ) and radial artery augmentation index ( AI , r =0.663 , P0.01 ) between the measurements from each device. Paired t-test showed that there were statistically significant differences between devices in cSBP [( 119.0±25.1 ) vs ( 106.1± 21.2 ) mm Hg , P0.01 ] and AI [( 73.5±15.4 ) %vs ( 67.1±22.5 ) % , P=0.03 ] . Bland-Altman plot suggested that the differences of the cSBP and AI between devices were ( 13.3±6.68 ) mm Hg and ( 6.3±16.8 ) %respective-ly. Within the limit of the consistency , the maximum moduli were 23.5mm Hg and 36.5%respectively , which in-dicated poor consistency. Conclusion The correlations in cSBP and AI were significant between two devices , while the consistencies were poor. It is unclear that these two devices can be used to measure CBP interchangeably in the clinical setting.