The following information comes from Sukie Crandall, who generously
sent an account of her experiences with Meltdown and Ruffle, two of
her ferrets with heart disease.

At first, your sick or recovering ferret will be a big drain on your
time, energy, and humor.  It's amazing how stubborn a sick ferret can
be.  If you're unfortunate enough to have a chronically ill ferret,
you may find that she becomes easier to deal with after a while, as
you both get used to her new routine and limitations.

You may have an assortment of medications for your ferret, whose
schedule and doses might change according to her health.  It's very
important to keep a complete and accurate chart.  Note how and when
medicines must be given, and whenever you give medicines write them
down and note the time.  Keep information on side effects, when to
skip doses, how to deal with missed doses or accidently doubled doses,
which medicines should not be given close together, which must be
shielded form light, and all other related information. Do not keep 
medications in a room which gets too hot, too cold, or too humid.
Never give a laxative close to when you give a medicine.  Be aware of
side-effects and interactions; for instance, some medicines increase
the chance of sunburn.

Pill cutters work much better than scalpels or other things, and a
tweezers will also be handy.  Keep in mind how different medicines
must be given, and find the best way for each to minimize the stress
to you and your ferret.  Some must be given in ways which minimize the
exposure to water or saliva.  They are most easily given with a narrow
pill gun such as your vet will probably carry, or mixed with a fatty
gel like Nutrical.  Liquids are pretty straight forward, but some
ferrets get good at bring those up or spitting them out.  If your vet
or the manufacturer's research pharmacists say they may be given with
fats try putting some Linatone or Nutrical on the ferret's nose and
while she is licking that off squirting in the dose at the posterior
side of the mouth.  (Do not use a laxative such as Petromalt for
these.)

You may need to cut down the sides of a litter pan for easy access,
and folded towels can be used to make gentle ramps.  For recovering
ferret who is ready for play but isn't quite up to speed yet, put
extra ramps, pillows, and climbing boxes around the room she'll be
playing in, to make it easier for her to get into and out of boxes and
jump down from furniture.  (Be careful not to let her be more active
than is safe, and always supervise her in play.)

Weak ferrets can't play normally, but they still enjoy encountering
new things.  Ruffle loved being carried for walks, being given herbs
to smell (especially mints and basil), having the sun on her belly
for short periods, listening to music (especially songs with her
name), hugs and kisses, and other peaceful entertainments.

If your ferret has a reduction in smell try moistening a cotton puff
or swab with a bit of perfume and putting it on the lower back above
the tail, and behind the ears.  That will keep it from sensitive areas
but let the ferret enjoy the comforting status of having a
ferret-proper level of smell.

If at all possible cancel your trips away.  If not possible have a
familiar, friendly, knowledgeable pet sitter such as a vet tech.  Have
a schedule, with some minor variations for interest, so that your pet
knows what to expect.  When your ferret has to be at the vet's office
bring along a favorite toy or blanket which smells like home.