Is it far or is it close? – clinically important examples of far and near fields
Acknowledgement
Piotr Lodzinski
Electrophysiologist
What will you learn?
- what far and near field means
- how to know what is in direct contact to my catheter
- what is clinical importance of all that
Your task for this lesson
- In which CS channel you can find the largest atrial signals and in which the largest ventricular signals
- Compare CS signals in Page 0 and Page 8. Can you spot the difference?
About this scenario
- Proper classification of potentials as a near-field and far-field potentials is one of the basic skills in EP
- Near-field potentials represent locally recorded electrical activity: most frequently near-field potentials are sharp in shape and have a high amplitude.
- Far-field potentials represent electrical activity observed from a distance: it is characterized by “blured” shape and lower amplitudes
- Final classification whether observed potential is near- or far-field may require observation during manipulation of the catheter or by observing capture of the structure with stimulation.
- In practice far-field and near-field potentials may help in catheter manipulation and placement (eg. within coronary sinus) or to assess lines of block.
What can be interesting
