What is the Far-Field IEGM vector?

What is the Far-Field IEGM vector?

• A. Can to RV coil
• B. LV coil to can
• C. SVC coil to can
• D. RV coil to can

Answer: (D)

The main idea here is that a far-field IEGM vector is formed between electrodes that lie far apart, giving a broad view of ventricular activation rather than a local, near-field signal. The classic setup uses the device can as one electrode and the RV coil as the other. Measuring from the RV coil to the can captures a wide-area ventricular signal, reflecting overall ventricular activation with less contamination from nearby structures, which is why it’s the typical far-field ventricular IEGM vector. Other pairs involve electrodes that are closer together or oriented toward regions other than the ventricles (such as left ventricular coils or the SVC/atrial area), producing signals that are more local or atrial-dominant and thus not as representative of global ventricular activation. The can-to-RV coil arrangement, essentially the same pair with opposite polarity, is the standard far-field ventricular recording.

The main idea here is that a far-field IEGM vector is formed between electrodes that lie far apart, giving a broad view of ventricular activation rather than a local, near-field signal. The classic setup uses the device can as one electrode and the RV coil as the other. Measuring from the RV coil to the can captures a wide-area ventricular signal, reflecting overall ventricular activation with less contamination from nearby structures, which is why it’s the typical far-field ventricular IEGM vector.

Other pairs involve electrodes that are closer together or oriented toward regions other than the ventricles (such as left ventricular coils or the SVC/atrial area), producing signals that are more local or atrial-dominant and thus not as representative of global ventricular activation. The can-to-RV coil arrangement, essentially the same pair with opposite polarity, is the standard far-field ventricular recording.