The medical section is asking for your history. So if you marked "yes" once, you'll have to mark "yes" for all subsequent medicals.
There is a comment section where you can provide greater detail. Something along the lines of "previously reported" or "previously reported, no change" works well depending on the situation. I've had PVC's since childhood related to open heart surgery and have never had trouble (after initial testing and documentation) holding a standard medical.