Introduction:Threshold testing of cardiac rhythm devices is essential to monitoring the proper functioning of these devices. However, the current method of applying multiple ECG leads to the patient and using a QRS based signal is burdensome and time consuming. We are presenting a completely new way to perform cardiac rhythm device threshold testing using pulse oximetry.
Methods: A standard pulse oximeter that is capable of displaying a plethysmographic waveform was used to perform threshold testing on 10 patients. Subsequently, standard QRS based threshold tests were performed for the same patients. The values were compared for accuracy.
Results: In nine out of the ten patients studied, the threshold tests between a pulse oximeter method and standard method were all within 0.25 V from each other, for both atrium and ventricle. In one patient, who was pacemaker dependent, the atrial threshold could not be accurately assessed.
Impression: We introduce a completely new, effective, and much faster method to perform cardiac rhythm device threshold testing. Further research should be performed to fully investigate this threshold testing approach.