This article reviews the most commonly used rate-adaptive sensor systems. Activity sensing (mainly accelerometer-based), minute ventilation, and closed-loop stimulation sensors using electrical bioimpedance are currently the primary systems. Sensor blending and sensor cross-checking are the most important modalities of sensor combination for heart-rate adaptation. Also, sensors for monitoring heart failure have been developed with the objective of identifying heart-failure exacerbations earlier. Intrathoracic impedance, intracardiac ventricular impedance, and peak endocardial acceleration have been used for hemodynamic monitoring. Future hemodynamic sensors will reliably assess crucial hemodynamic variables such as preload, afterload, left ventricular ejection fraction, and stroke volume.
Bibliographical noteFunding Information:
W.W.X. is supported by a Fellowship grant from the Cardiac Arrhythmia Center, Cardiovascular Division, University of Minnesota .
Copyright 2013 Elsevier B.V., All rights reserved.
- Hemodynamic sensor
- Physical sensor
- Rate adaptation