PP.06.07

Abstract

Objective: There is a substantial gradient between aortic and brachial pulse pressure (PP), generally called pulse pressure amplification (PPA). Several studies have reported that PPA is related to cardiovascular risk factors and predicts cardiovascular mortalities. PPA was usually calculated with noninvasively measured (NIM) brachial and aortic PP, but there are few studies that have evaluated the accuracy of NIM PPA compared with invasively measured (IM) PPA. The aim of this study was to compare the value of PPA assessed with invasive and noninvasive method. Design and method: 88 patients undergoing elective coronary angiography were enrolled in this study. Brachial and central BPs were measured noninvasively with Mobil-O-Graph®, invasively with a fluid-filled catheter. PPA was defined as brachial PP minus aortic PP. Results: The mean values of BP indices are shown in Table. NIM brachial SBP was underestimated by about 19 mmHg and DBP was overestimated by about 15 mmHg, resulting in underestimation of NIM brachial PP by about 34 mmHg (IM vs NIM brachial PP: 87.3 ± 23.3 vs 53.4 ± 14.8 mmHg, p < 0.001). NIM aortic SBP was slightly and DBP was considerably overestimated, leading to underestimation of NIM aortic PP by about 13 mmHg (IM vs NIM aortic PP:72.9 ± 22.5 vs 60.0 ± 18.2 mmHg, p < 0.001). As a result, NIM aortic PP was higher than brachial PP in contrast to IM PPs (IM vs NIM PPA: 14.4 ± 9.5 vs -6.6 ± 7.6 mmHg, p < 0.001). The difference between IM and NIM PPA was 20.9 ± 11.0 mmHg.Conclusions: The mean value of invasively measured PPA was positive in consistent with general understanding that is brachial PP is higher than aortic PP. However, the mean value of NIM PPA was negative mainly due to the considerable underestimation of NIM brachial SBP. In addition to substantial differences between aortic BP estimating methods, we should take into consideration the measurement error of brachial BP when assessing the PPA value.