I am sorry to hear about all the problems with Maizie! The licking of the leg is not uncommon. With nerve damage, parts or all of the limb can can 'feel numb' or 'asleep' --- this funny feeling can lead to pets licking or even chewing their arms or feet. This can become a serious problem if the nerve sensation does not return and the pet does not stop licking/chewing the limb. I have unfortunately had to amputate several limbs due to this complication from nerve damage.
It is not uncommon for heart sounds to be apparent on an exam when a only four months prior, nothing was heard. Reasons? It may not have been present at that time, some heart sounds are dependent upon heart rate so may be easily to hear at one speed versus another, purring/shivering/high respiration rate can make it difficult to hear, some heart sounds are very dependent upon placement of the stethescope and mild changes may lead to normal sounds or abnormal sounds.
As far as the heart problem, the difficulty is that a echo is needed to in order to make a more exact prognosis and treatment plan. This can be expensive.
Was Maizie tested for heartworms? Any other testing? How is she doing now?
Christopher A. Lee, D.V.M., C.V.L.S.
Promoting surgical options and pet comfort through the use of lasers.