Thank you Anna and LittleGreyCat. We're not in the UK, so don't have access to the same services, eg physiotherapy or any forms of medically supervised exercise. Aqua is available at the nearest gym. There are no yoga classes, but we have done yoga at home in the past, so I think we may go back to doing that. There is a weekly Tai Chi class, which we dropped out of because it is at a very inconvenient time for us both, but I shall try to get back to that as well.
LGC, I get your point about asking the question on a forum with heart issues, but the only one I know of is in French and I'm not as confident posting in French! If you know of one, I'd be very grateful. (Having said that, shortly after posting my question the weekly email came through from this forum with links to a programme of "10 minutes pour votre cœur" - 10 minutes of exercise for your heart. Synchronicity at work there?)
Thank you again.