I concur with Mike.......verify. It is not enough to just have medical insurance, you need medical evacuation. The costs for medical evacuation, especially from distant spots of the ocean, can be enormous. On one cruise, we had a helicopter meet the ship off Spitzbergen at 79 degrees north. That helicopter to Longyearben and plane to Tromso had to be pretty pricey let alone the return to US.
Make sure you have good medical evacuation insurance. Investigate plans like from Medjet or Amex if that is the only insurance you are lacking.
Doopydozer, you make me glad I have US instead of Canadian insurance. Of course, that could all change.