I rang Amex cc insurance, got put through to Chubb insurers. The woman said that they won't cover hypertension with the credit card policy, even if you pay extra. So looking around for other options. Gets complicated if you've already paid some prepaid expenses on the charge card. It appears that that credit card insurance is really only of use for the rental car excess it covers.
Just wondering, can anyone recommend a multi trip insurer that you've had good experience with. I might go down that route and just pay up!