Effect of Autonomic Stressors on Rate Control in Pacemakers Using Ventricular Impedance Signal
- 14 January 2004
- journal article
- Published by Wiley in Pacing and Clinical Electrophysiology
- Vol. 27 (1), 24-32
- https://doi.org/10.1111/j.1540-8159.2004.00381.x
Abstract
The aim of this study is to evaluate the heart rate adaptation obtained by a pacemaker, based on a measure of ventricular impedance in patients undergoing autonomic challenges. The evaluation procedure was based on the analysis of the mean value (MV) and heart rate variability (HRV) of RR and systolic pressure intervals, according to a set of neurovegetative stressors (controlled respiration in supine position and during active standing; mental stress; handgrip, and noninvasive sinusoidal stimulation of carotid baroreceptors). Each test lasted 5 minutes. Fifteen chronotropic incompetent patients first implanted, were studied three months after implantation. ECG, respiration activity, and noninvasive blood pressure were monitored. HRV was evaluated by spectral analysis. Variability in the low frequency (LF) and high frequency (HF) bands was compared by computing percentage and absolute powers. We found that baseline HR was 72.2 ± 5.5 beats/min, in mental stress was 76.8 ± 7.8 beats/min, in handgrip was 79.2 ± 6.3 beats/min, and in active standing was 80.9 ± 8.6 beats/min (P < 0.01, Friedman's test). During active standing, LF component was significantly higher with respect to baseline (25.7% of total power in standing; 9.4% in baseline, P < 0.01) and it was synchronous to the LF component of the arterial pressure variability. Carotid activation/deactivation by neck suction induced synchronous changes in the paced rates. In conclusion, closed loop strategy based on ventricular contractility continuously controls heart rate by tracking the sympathetic modulation to the heart. (PACE 2004; 27: 24–32)Keywords
This publication has 15 references indexed in Scilit:
- Respiratory sinus arrhythmia and cardiovascular neural regulation in athletesMedicine & Science in Sports & Exercise, 1998
- Heart Rate VariabilityCirculation, 1996
- Rate-responsive pacing based on sympathetic activityMedical & Biological Engineering & Computing, 1993
- Autonomic Nervous System Controlled Closed Loop Cardiac PacingPacing and Clinical Electrophysiology, 1992
- Right ventricular conductance to establish closed-loop pacingEuropean Heart Journal, 1992
- Cardiovascular neural regulation explored in the frequency domain.Circulation, 1991
- Computer analysis of the electrocardiogram during esophageal pacing cardiac stressIEEE Transactions on Biomedical Engineering, 1991
- Automatic Adjustment of Pacing Parameters Based on Intracardiac Impedance MeasurementsPacing and Clinical Electrophysiology, 1990
- A New Multisensor Pacing System Using Stroke Volume, Respiratory Rate, Mixed Venous Oxygen Saturation, And Temperature, Right Atrial Pressure, Right Ventricular Pressure, And dP/dtPacing and Clinical Electrophysiology, 1988
- Cardiovascular variability signals: towards the identification of a closed-loop model of the neural control mechanismsIEEE Transactions on Biomedical Engineering, 1988