A New Tonometric Device for Radial Augmentation Index and Subendocardial Viability Ratio: Potential Use in Health Screening

Abstract

Augmentation index (AIx) and subendocardial viability ratio (SEVR) are widely accepted indices of wave reflection and myocardial oxygen demand relative to supply. This study aimed to validate a new tonometric device (IIM‐2010A) for obtaining AIx and SEVR from radial artery. A total of 68 outpatients (32 men and 36 women) aged 20 to 76 years (44.7±16.6 years) recruited from a health screening center participated in the study. AIx was obtained from radial pressure using the HEM‐9000AI and IIM‐2010A devices, while SEVR was measured from carotid pressure with the tonometric method and from radial pressure by the IIM‐2010A device. In a subgroup of 24 patients, the measurements of AIx and SEVR were repeated after an interval of 10 minutes. The correlation of radial AIx between the IIM‐2010A and HEM‐9000AI devices was highly significant (r=0.956, P<.01). Radial SEVR determined from IIM‐2010A was also highly related to carotid SEVR (r=0.864, P<.01), although the value was about 13.1% lower. There was no statistically significant difference between the repeated measurements of both indices. The lower coefficient of variation (2.9% vs 4.3% for AIx, 3.3% vs 4.1% for SEVR) and higher intraclass correlation coefficient (0.96 vs 0.91 for AIx, 0.93 vs 0.86 for SEVR) of IIM‐2010A confirmed better short‐term reproducibility, compared with the HEM‐9000AI device and carotid tonometry. The new tonometric device IIM‐2010A is effective and reproducible in calculating radial AIx and SEVR and has potential use in health screening.

The correlation between subendocardial viability ratio and the degree of coronary artery stenosis in patients with coronary heart disease and its predictive value for the incidence of short-term cardiovascular events

“…Previous studies have shown that central pressure is more strongly predictive of the cardiovascular risk compared to peripheral pressure [22]. The radial and coronary artery parameters show a strong correlation; therefore, the radial artery parameters could alone reflect the hemodynamic changes [23].…”

Radial augmentation index may be an effective predictor of vascular calcification in patients on peritoneal dialysis

“…The left radial arterial waveform was recorded using the tonometric method with an automatic waveform analyzer (HEM-9000AI; Omron Healthcare, Kyoto, Japan), as described previously [14][15][16], after 10 min of rest in a sitting position. RAI was calculated automatically using the following equation [14,16]: RAI ¼ ðsecond peak SBP À DBPÞ=ðfirst peak SBP À DBPÞ Â 100%: RAI was corrected by an average heart rate of 75 bpm. The final value of mean arterial pressure (MAP) and RAI was the mean value of measurements in triplicate at intervals of 1 min.…”

Accuracy Evaluation of Robotic Tonometry Pulse Sensor System Based on Radial Artery Pulse Wave Simulator

“…In particular, pulse diagnosis is an important method in identifying a patient's condition or health status in Korean medicine [5]. In recent decades, many studies of Eastern medicine have aimed to objectify, quantify, and automate wrist pulse diagnosis by employing modern sensors [6][7][8][9]. Recently, the use of pulse wave measurements, such as tonometry, wrist band, and photoplethysmography (PPG), has been increasing in the fields of integrated medicine and Western medicine.…”

“…Non-invasive methods are usually performed using a pressurized cuff on the upper arm, which is called the oscillometric method. The tonometric method is a non-invasive blood pressure measurement method because it is capable of measuring not only blood pressure but also other vascular indices, such as the augmentation index (AIx) [2,4,6], pulse wave velocity [13][14][15], and pulse pressure index (PPI) [10,16,17]. However, the tonometric method is not widely used because it is difficult to precisely measure both the radial pulse waveform and pressurizing force from a single sensor and often obtains different results depending on the user's operation ability.…”