Thanks for the feedback
Peaches does have her blood tested & urine as well twice per year because our girl is a survivor of kidney failure due to a double whammy of 2 types of leptos infections & a Lyme disease-related tick bite back in the fall of 2009/winter 2010....
The vet does check her heart but nothing is there for now it seems.
Needless to say , we almost lost her but she's a very tough survivor , after a form of dialysis for week at the vets ( she was given a 50/50 chance of living
) plus force feeding w/meds for 2 months , all is well for now
Since it is an extremely very cold winter this year out here , maybe it's just another sign of aging
, as just recently we went through a mild spell for a couple of days & her back feet seemed to be correspondingly slightly warmer for now