Fig. 4. Patient feedback and adaptive pacing functions.

(A) Schematic illustration of a transient closed-loop system. (B) Demonstration of the patient awareness function using a multi-haptic module. Accelerometer data (z-axis) corresponds to vibrations of the haptic actuators. (C) Results of clinical tests with a healthy human subject. (i) Calculated physical activity and (ii) respiratory rate using data from the respiratory module. (iii) Comparison of the heart rate (black) of a healthy human subject monitored by the cardiac module and rate-adaptive pacing signals (red) processed from the algorithm. (iv) Calibrated and measured changes in core body temperatures using data from the respiratory module. (v) Representative SpO₂ measurements from the hemodynamic module.