Related Experiment Video
Updated: Mar 27, 2026
Software for Analysis of Heart Rate and Blood Pressure Time-series Data from the Valsalva Maneuver
Published on: June 27, 2025
Impact of heart disease and calibration interval on accuracy of pulse transit time-based blood pressure estimation
Xiaorong Ding1, Yuanting Zhang1, Hon Ki Tsang1
1Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, People's Republic of China.
Insights
Continuous blood pressure monitoring using pulse transit time (PTT) is promising but accuracy is affected by heart disease and calibration frequency. Longer intervals and cardiovascular disorders reduce PTT-based blood pressure estimation reliability.
Area of Science:
- Biomedical Engineering
- Cardiovascular Research
- Medical Devices
Background:
- Continuous blood pressure (BP) monitoring without a cuff is crucial for hypertension management.
- The pulse transit time (PTT) method offers a promising approach for cuffless BP measurement.
- Accuracy challenges hinder the widespread clinical adoption of PTT-based BP estimation.
Purpose of the Study:
- To investigate the impact of heart disease on PTT-based BP estimation accuracy.
- To evaluate the effect of different calibration intervals on PTT-based BP measurement reliability.
- To identify factors influencing the accuracy of cuffless continuous BP monitoring.
Main Methods:
- Investigated a PTT-BP algorithm's accuracy in 37 healthy subjects and 48 patients with heart disease.
- Assessed accuracy at calibration intervals of 15 minutes, 2 weeks, and 1 month.
- Compared systolic and diastolic BP estimation accuracy across groups and intervals.
Main Results:
- Systolic BP estimation accuracy was significantly lower in heart disease patients compared to healthy subjects.
- Diastolic BP estimation was more accurate in heart disease patients than in healthy subjects.
- BP estimation accuracy decreased with longer calibration intervals for both systolic and diastolic BP.
Conclusions:
- Heart disease and calibration interval significantly influence PTT-based BP estimation accuracy.
- Optimizing calibration strategies and considering patient cardiovascular status are essential for improving cuffless BP monitoring.
- Further research is needed to enhance the reliability of PTT for continuous hypertension management.
Abstract:
Continuous blood pressure (BP) measurement without a cuff is advantageous for the early detection and prevention of hypertension. The pulse transit time (PTT) method has proven to be promising for continuous cuffless BP measurement. However, the problem of accuracy is one of the most challenging aspects before the large-scale clinical application of this method. Since PTT-based BP estimation relies primarily on the relationship between PTT and BP under certain assumptions, estimation accuracy will be affected by cardiovascular disorders that impair this relationship and by the calibration frequency, which may violate these assumptions. This study sought to examine the impact of heart disease and the calibration interval on the accuracy of PTT-based BP estimation. The accuracy of a PTT-BP algorithm was investigated in 37 healthy subjects and 48 patients with heart disease at different calibration intervals, namely 15 min, 2 weeks, and 1 month after initial calibration. The results showed that the overall accuracy of systolic BP estimation was significantly lower in subjects with heart disease than in healthy subjects, but diastolic BP estimation was more accurate in patients than in healthy subjects. The accuracy of systolic and diastolic BP estimation becomes less reliable with longer calibration intervals. These findings demonstrate that both heart disease and the calibration interval can influence the accuracy of PTT-based BP estimation and should be taken into consideration to improve estimation accuracy.
Related Concept Videos
01:25Errors occurring during blood pressure monitoring
Several factors...
01:28Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
01:23Assessment of blood pressure in brachial artery(two-step method)
01:21Sites for measuring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
01:30Equipments Used To Measure Blood Pressure
This invasive approach involves cannulating a peripheral artery. During each cardiac contraction, pressure generates mechanical motion within the catheter, transmitted through rigid, fluid-filled tubing to a transducer. This transducer converts mechanical motion into electrical signals displayed as waveforms on a monitor. An automatic flushing system prevents blood backflow. Due to the potential risk of unexpected arterial blood loss, this method is primarily used in intensive...
01:17Measurement of Blood Pressure