Personalized physiologic flow waveforms improve wave reflection estimates compared to triangular flow waveforms in adults

Date
2021-04-21
Journal Title
Journal ISSN
Volume Title
Publisher
American Journal of Physiology - Heart and Circulatory Physiology
Abstract
Central aortic pressure waveforms contain valuable prognostic information in addition to central systolic pressure. Using pressure-flow relations, wave separation analysis can be used to decompose aortic pressure waveforms into forward- (Pf) and backward-traveling (Pb) components. Reflection magnitude, the ratio of pressure amplitudes (RM = Pb/Pf), is a predictor of heart failure and all-cause mortality. Aortic flow can be measured via Doppler echocardiography or estimated using a triangular flow waveform; however, the latter may underestimate the flow waveform convexity and overestimate Pb and RM. We sought to determine the accuracy of a personalized synthetic physiologic flow waveform, compared with triangular and measured flow waveforms, for estimating wave reflection indices in 49 healthy young (27 ± 6 yr) and 29 older adults [66 ± 6 yr; 20 healthy, 9 chronic kidney disease (CKD)]. Aortic pressure and measured flow waveforms were acquired via radial tonometry and echocardiography, respectively. Triangular and physiologic flow waveforms were constructed from aortic pressure waveforms. Compared with the measured flow waveform, the triangular waveform underestimated Pf in older, but not young, adults and overestimated Pb and RM in both groups. The physiologic waveform was equivalent to measured flow in deriving all wave reflection indices and yielded smaller mean absolute biases than the triangular waveform in all instances (P < 0.05). Lastly, central pulse pressure was associated with triangular, but not physiologic, mean biases for Pb and RM independent of age or central arterial stiffness (P < 0.05). These findings support the use of personalized physiologic flow waveforms as a more robust alternative to triangular flow waveforms when true flow cannot be measured. NEW & NOTEWORTHY We demonstrate that triangular flow waveforms overestimate wave reflection indices, particularly at higher central pulse pressures independent of age or carotid-femoral pulse wave velocity. In contrast, personalized physiologic flow waveforms provide equivalent wave reflection estimates as measured flow waveforms, thereby offering a more robust alternative to triangulation when aortic flow cannot be measured.
Description
This article was originally published in American Journal of Physiology - Heart and Circulatory Physiology. The version of record is available at: https://doi.org/10.1152/ajpheart.00747.2020
Keywords
arterial stiffness, central blood pressure, reflection magnitude, validation study, wave separation analysis
Citation
Shenouda, Ninette, Joseph M. Stock, Jordan C. Patik, Julio A. Chirinos, and David G. Edwards. “Personalized Physiologic Flow Waveforms Improve Wave Reflection Estimates Compared to Triangular Flow Waveforms in Adults.” American Journal of Physiology-Heart and Circulatory Physiology 320, no. 5 (May 1, 2021): H1802–12. https://doi.org/10.1152/ajpheart.00747.2020.