Feline Cardiomyopathy Breaks More Hearts Than One

                       Because our veterinary hospital provides after hours emergency care for our clients, our cell phone is monitored 24 hours daily.  We are occasionally awakened at night by concerned pet parents or livestock owners whose animals don’t know the time of day.  Some of these phone calls consist of giving advice and providing reassurance.  Others require immediate instruction and attention.

 

                        When our emergency phone rang in the wee hours of the morning recently, I was not surprised, but my heart sank when it was my sister Cindy, a registered veterinary technician who lives near Columbus.  She tearfully described how her husband had been awakened by their Border Collie alerting him that something was wrong with their cat, “Timmy.”

                        This lovable, large, orange, longhaired cat adopted from the Humane Society of Allen County, was a birthday gift to Cindy from my husband and me.  Because we are firm believers that cats do better in pairs, we adopted a second orange and white female cat at the same time that Cindy named “Squeak” to be Timmy’s companion. 

                        Did I mention how perturbed Cindy’s husband, Gary, was that we enabled Cindy’s pet addiction by growing their four dog family by not one, but two cats?

                        As all good cats do, Timmy quickly realized Gary was the master of the house and possibly not as in love with him as Cindy.  Timmy knew his first mission in his new home needed to be to align his “staff.”  As such, he quickly chose Gary to be “his person.”  In short order, Timmy had Gary “hook, line, and sinker” and the two were fast friends.

                        Cindy’s emergency phone call was to get reassurance that the decision they were about to make was correct. When awakened by their dog, Gary readily discerned that Timmy was lying in an odd location and was in obvious distress.  They quickly scooped him up and drove directly to nearby MedVet, a 24 hour emergency care facility, where Timmy was diagnosed with an aortic thromboembolism (ATE) or “saddle thrombus.”

                        This painful, acute condition occurs when a clot that has formed in the left upper heart (atrium) gets dislodged and enters the aorta.  Unfortunately, in cats this clot usually makes its way to the area where the aorta splits to supply blood to the rear legs.  The clot sits at this “saddle-shaped” area of the aorta and blocks most, if not all, of the blood supply to the rear legs.

                        Without proper blood circulation, the back limbs quickly become agonizingly painful, then cold and extremely weak or paralyzed.  In cats, ATE is usually a manifestation of underlying heart muscle disease or hypertrophic cardiomyopathy (HCM) that is characterized by thickened, stiff heart walls. Cats can also get dilated cardiomyopathy (DCM) that occurred more frequently in the past due to previously inadequate taurine supplementation of cat foods.

                        Today, the primary cause of ATE in cats is HCM and this disease is genetic in many purebred cats including Maine Coon, American Shorthairs, and Persians. Cats that are not purebred, but share these breeds’ genetics, are definitely more at risk.  Such was the case for Timmy as he appeared to have his fair share of Maine Coon breeding.

                        Once cats are afflicted with ATE, their cardiomyopathy has usually been longstanding, and their prognosis is poor.  The majority of cats die or do not respond to treatment, therefore, pet owners will often choose humane euthanasia for this devastating condition.  Recovery, when it occurs, can take days to weeks, but there is a very high likelihood of recurrence of ATE or sudden death. Expected lifespan after an ATE is quite short due to difficulties in managing the underlying HCM or recurrent ATE.

                        Out of deep devotion and concern for their beloved cat, Cindy and Gary elected to terminate Timmy’s suffering by having him humanely euthanized.  Timmy’s heart was not the only one broken, as the emptiness the couple experienced in the weeks that followed was immeasurable.  While pet loss is always difficult, the unexpected losses are, without question, the worst.

                        Timmy’s tragedy reminds me to remind you to know your veterinarian’s after hours policy as not all veterinarians provide emergency services.  In Timmy’s case, and that of many others, time is of the essence to limit pain and suffering.  Know who to call and where to go when your pet experiences an emergency as it can be the difference between life and death.

Author:  Dr. Bonnie Jones
This column is a tribute to “Sally Soo,” our Siamese mix, that also lost her life to ATE.
Image courtesy of winnond at FreeDigitalPhotos.net