Aching throughout leg a week after cardiac catheter ablation? The leg below the catheter insertion point, down to the foot. Mild aching but annoying.

Maybe. You have a large clot in hour groin from the catheter or maybe it was from an odd positioning of your leg during the procedure . At ant rate it does not sound serious since it is just an annoying ache. It's really hard to tell without knowing more about where in your leg it aches, if constant or not. Have you tried tylenol (acetaminophen) ? Hope you feel better !
Exam. Was this the leg which was used to thread the catheter? The discomfort could be from muscle, blood vessel or nerve irritation. Your physician could tell better after he/she examines your leg.