Maria, these should be of help to you:
http://fhl.sonic-weasel.org
 and from
http://www.ferretcongress.org:
>Cardiomyopathy and other heart problems:
>http://www.vetheart.com/ heart info from veterinary cardiologists
>http://www.smartgroups.com/vault/ferrethealth/cardiomyopathy.txt
>http://www.miamiferret.org/fhc/cardiomyopathy.htm
>http://www.miamiferret.org/fhc/cardio.htm
>http://home.att.net/~hhoefer/ferret_heart.htm
 
Survival time depends on the type of cardiomyopathy and the fit of the
meds (Ultrasound helps with each of those two things.) as well as there
being individual factors and the importance of keeping stressing factors
under control.  We've had one go as long as 1 and 1/2 years with
cardiomyopathy complicated by ventricular bigemini once she was put on
Digoxin (even though she had originally been expected to die in weeks
from her rhythm problem) and have heard of ones who had uncomplicated
cardiomyopathy who went longer with careful care.  On the other hand, we
have had ones who were also sick with other terminal things who went
quickly from their multiple burdens and increased medicating difficulties
when there are medication conflicts between terminal conditions (problems
which one must expect in those rare situations), and I guess the quickest
non-complicated cardiomyopathy individual we've had was one with
hypertrophic cardiomyopathy (the rare kind in them which is usually not
found till it is advanced or till it kills) and she went something like 6
to 9 months.  Sorry that I can't recall the length of time.  Treatment
for cardiomyopathy can't cure it but it does absolute wonders for
improving both the quality of life and the quantity of time remaining.
There are multiple truly excellent meds out there and which ones are
used depends on the nature of the disease, it's presentations in the
individual, and how it changes over time in the individual.
 
BTW, I think maybe it's been about a week or two since I've said this (I
know -- people are yawn through the needed repetition.): I'm not a vet.
 
Ailigh, no matter where adrenal ferrets are located the presentations
vary widely.  The photos tend to show advanced cases or typical
presentations.  Off the top of my head here are some symptoms of adrenal
disease.  Note that a ferret may show a number of these or may even show
none at all, then suddenly present with a life threatening complication
(which happened with one of our ferrets when his urethra blocked
completely even though he had no adrenal symptoms so he needed an
emergency appointment to empty him and them emergency surgery about 12
hours later to remove his disease adrenal at which point he cleared up
beautifully).  I am sure to miss some of the symptoms in this list so
others should chime in.
 
1. bilaterally symmetrical fur loss ANYWHERE on the trunk, limbs, or
   top of head (loss of fur on the tail only may be from adrenal growths
   but is more often dermal)
2. pear shape from fat depositing below the waist; some ferrets also
   get very thin above the waist
3. swollen vulva
4. swollen nipples
5. fur feels more coarse from loss of undercoat
6. odor change
7. unusual fat distribution (This can also be internal; a few ferrets
   get fat deposits in the thorax which is painful and can be life
   threatening, The fat reallocation can at times increase fat
   distribution around lymph nodes which scares some people into
   thinking "lympho".)
8. increased incidence of ulcers
9. accelerated bone density loss
10. repeated vaginal infections
11. repeated urinary tract infections
12  dangerous (life threatening as it worsens) levels of anemia
13. behavioral changes (Ferret may act more kit like, or may become
    inappropriately sexually aggressive, or may suddenly baby other
    ferrets, toys, or humans to much greater extents.  One odd behavior
    we've seen is one who would urinate on the head and shoulders of the
    youngest ferret in the household when her two took off.)
14. dysuria from swollen prostate
15. thin skin, sometimes increased blackhead, and sometimes skin sores
[Posted in FML issue 4214]