For atrial tachycardia mapping, which map is created and when should remapping occur?

• A. Structural map; remap if cycle length changes more than 50%
• B. Activation map; remap if TCL has changed more than 10%
• C. Voltage map; remap if QRS morphology changes
• D. Activation map; remap if TCL changes more than 50%

Answer: (B)

Activation mapping is used to visualize the exact sequence of atrial activation during atrial tachycardia, showing where activation begins and how it propagates through the atria. This map captures activation times relative to a reference so you can identify the focal source or the path of a reentrant circuit.

Remapping should be considered when the tachycardia cycle length changes by more than about 10%. A significant change in cycle length can alter propagation patterns and the circuit geometry, making the previous activation map inaccurate for the new rhythm.

Other maps serve different purposes: a structural map depicts anatomy and is static; a voltage map highlights scar or low-voltage zones; and remapping based on QRS morphology changes isn’t the standard criterion for atrial tachycardia mapping.