Optimizing non-invasive blood pressure estimation using pulse transit time.

Continuous blood pressure (BP) monitoring during exercise is an important means to ensure exercise safety, particularly in seniors and individuals with various comorbidities. Use of automated BP monitors is limited during exercise. Pulse transit time (PTT) has been suggested for non-invasive BP monitoring however its implementation into clinical practice was hampered by lack of non-expensive practical solutions. The goal of this project was to introduce and to test a practical low-cost solution for using PTT to estimate BP during exercise. Our approach was based on obtaining 3 calibration points during different levels of exertion for each subject and utilizing the resulting individualized BP estimation equitation for patient-specific monitoring of BP during home-based exercise. Evaluation of the proposed approach showed that the mean difference between reference systolic BP (SBP) and estimated systolic BP was 0.0 mmHg. The optimal way to calculate PTT has been established by comparison of three main characteristic points used to derive PTT.