Although compelling evidence has established the physiological and clinical relevance of aortic SBP (a-SBP), no consensus exists regarding the validity of the available methods/techniques that noninvasively measure it.
The systematic review and meta-analysis aimed to determine the accuracy of commercial devices estimating a-SBP noninvasively, which have been validated by invasive measurement of a-SBP. Moreover their optimal mode of application, in terms of calibration, as well as specific technique and arterial site of pulse wave acquisition were further investigated.
The study was performed according to the PRISMA guidelines; 22 eligible studies were included, which validated invasively 11 different commercial devices in 808 study participants.
Overall, the error in a-SBP estimation (estimated minus actual value) was −4.49 mmHg [95% confidence interval (CI): −6.06 to −2.92 mmHg]. The estimated (noninvasive) a-SBP differed from the actual (invasive) value depending on calibration method: by −1.08 mmHg (95% CI: −2.81, 0.65 mmHg) and by −5.81 mmHg (95% CI: −7.79, −3.84 mmHg), when invasively and noninvasively measured brachial BP values were used respectively; by −1.83 mmHg, (95% CI: −3.32, −0.34 mmHg), and by 7.78 mmHg (95% CI: −10.28, −5.28 mmHg), when brachial mean arterial pressure/DBP and SBP/DBP were used, respectively.
Automated recording of waveforms, calibrated noninvasively by brachial mean arterial pressure/DBP values seems the most promising approach that can provide relatively more accurate, noninvasive estimation of a-SBP. It is still uncertain whether a specific device can be recommended as ‘gold standard’; however, a consensus is currently demanding.