Sensor induced tachycardia
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Sensor induced at tachycardia occurs when limb movement during exercise, rapid breathing or acidosis causes the sensor of a modern pacemaker to fire at an inappropriately rapid rate.
Pathophysiology
There have been advances in the technology of modern pacemakers such that these pacemakers can increase the heart rate in response to metabolic demands such as acidemia or hypercapnea as well as physiologic stimuli such as exercise or tachypnea. Sensor induced tachycardia occurs when these pacemaker sensors misinterpret stimuli and misfire.
Causes
Sensor induced tachycardia occurs when these pacemaker sensors misinterpret stimuli and misfire. Stimuli that may cause the pacemaker to misfire include the following:
- Electrocautery during surgery
- Excess limb movement
- Fever
- Hyperventilation
- Loud noises
- Vibrations
Differential Diagnosis
Sensor induced tachycardia must be differentiated from pacemaker mediated tachycardia. The rate associated with pacemaker mediated tachycardia is usually slower at around 120 to 130 beats per minute while the heart rate associated with sensor induced tachycardia is more rapid at a rate of 162 180 beats per minute.
Diagnosis
Electrocardiogram
The ventricular rate is at the upper limit of the pacemakers range at 162 180 bpm.
Treatment
Placement of the magnet on the patient will terminate the tachycardia.