Noninvasive Assessment of Carotid Pulse Pressure Values: An Accelerometric-Based Approach

Objective: Central pulse pressure (cPP) is increasingly investigated as possible independent predictor of cardiovascular risk and carotid pulse pressure (carPP) can be used as a surrogate of cPP. Despite its importance, carPP measurement remains challenging in clinical practice. The aim of this study was to introduce a new easier-to-use method for noninvasive carPP evaluation based on the use of a MEMS accelerometer. Methods: carPP values (carPP
_acc
) were obtained in 22 subjects (10 males, 47 ± 17 years, hypertension: 50%) postprocessing and double integrating the accelerometric signals. carPP
_acc
measurements were compared with tonometric assessments (carPP
_ton
), and ultrasound-derived measurements (carPP
_US
). Moreover, accelerometric carotid pressure waveforms (P
_acc
) were contrasted in terms of shape to those obtained by tonometry (P
_ton
) and ultrasound images elaboration (P
_US
), calculating the root mean square error (RMSE
_ton
, RMSE
_US
) and the regression coefficients (r
_ton
and r
_US
). Moreover, both the repeatability and reproducibility analyses were performed. Results: carPP
_acc
values (45.9 ± 10.6 mmHg) were significantly correlated with carPP
_ton
(47.5 ± 11.3 mmHg) and carPP
_US
(43.3 ± 8.4 mmHg) assessments (R = 0.94, p <; 0.0001 and R = 0.80, p <; 0.0001, respectively). The validity of the accelerometric approach was confirmed by morphological parameters (RMSE
_ton
= 5 ± 1.95 mmHg, RMSE
_US
= 5.5 ± 2.3 mmHg, r
_ton
= 0.94 ± 0.04, r
_US
= 0.93 ± 0.04). Coefficient of variation (CV) was equal to 6.2% for the repeatability analysis, while CV values for interoperator and intersession reproducibilities were 8.9% and 9.4%, respectively. Conclusion: The proposed approach, providing an easier and more available measurement, could represent a valid alternative to existing and used technique for carPP assessment.