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Canine Heart Issues/DCM/Hypothyroidism - MUST READ!

Updated: May 16, 2021

The proof is in the pudding and I think we finally have it or at least enough to start the life saving conversation!

Let me start this with... I'M NOT A VET... But I will show you four different Holter monitor tests for the same dog, which I feel, proves that too high a dose of thyroid medication can cause heart issues. Look at the tests and you be the judge.

I was approached sometime back by a reputable Doberman breeder who made the statement that thyroid medications, specifically, too high a dose can cause heart problems and she had the proof! I immediately asked for her test results, the full story and offered her total anonymity.

The breeder, let's call her Tina, has been breeding Dobermans for many years now. She shows her dogs, health tests regularly and truly loves the breed.

I met Tina back when I was showing our Doberman, Gunner. We got to know each other over the years and have maintained a relationship. Tina knows OUR story, and in particular, knew Gunner and his story.

So let me back up a bit.

I got Gunner as a puppy from a Doberman breeder (not Tina). In hindsight, he had health issues from the minute I got him. Whether it was bad gas, "allergies", diarrhea, staph infections, ear infections, rashes, blotchy skin colour changes and more. My goodness, it seemed like I was constantly either on my way to the vet or coming back from the vet. My VISA was at times warm to the touch from all the scanning!

As time went by, Gunner started showing dog aggression and then by the time he was two, it was human aggression. He attacked me.

Over the course of 2.5 years, I spent over $10,000.00 in vets, medications, supplements, vitamins, special foods, special shampoos, behaviorists, trainers and the list goes on. I will admit, many of these things improved symptoms, but others just popped up.

Just before his third birthday, Gunner was diagnosed as "dangerously low" Hypothyroid and within no time, all the problems almost completely disappeared! I will admit though, where there was an exceptional POSITIVE change in his over all health and behavior - he did remain "dicey" at times. Over his remaining years of life - he did have some minor issues. I thought nothing of these issues as he was WAY better! I became complacent.

Sadly, Gunner died at just over 7 years old.

It was an amazingly beautiful spring day, Tim, Gunner and I were playing in the yard, time just stopped and our hearts were broken. Gunner literally dropped dead while playing with us. The diagnosis of Dilated Cardiomyopathy (DCM) was given as the cause.

So jump forward to October 2018, I published Heart Dog - Gunner's Story. The reason for this was simply because I was alarmed at how close I had been to euthanizing Gunner due to his aggression. In fact, so close that I took him to the euthanasia appointment but changed my mind in the parking lot. I was also alarmed that it took me 2.5 years to finally get this dog diagnosed properly! Our poor Gunner was sick for almost three years and all I did was put "band-aids" on the problems.

But more so... What if people were putting down their aggressive dogs and it turned out it was only Hypothyroidism? There were claims made that this was happening on a regular basis - what if it was true? So I wrote the book and the emails started coming in hand over fist.

I started doing MORE researching and in doing so, found a remarkable group on Face Book called "Hypothyroidism In Dogs" and immediately joined! I didn't post anything for quite some time but just lurked in the background learning and reading.

Then the post came up that knocked the wind out of me... The question was asked - does anyone think that Hypothyroidism is linked to DCM? I immediately felt my own blood pressure go up. As I followed the post, I got sicker and sicker. The two major points made were this:

  1. Hypothyroidism has over 70 symptoms - one of which is Heart Arrhythmia. Not treated, this can cause DCM.

  2. A dog that is on too high of a thyroid medication can ALSO have arrhythmia which not adjusted can cause DCM.

Gunner was 85-90lbs of lean muscle and when originally diagnosed, he was given .8, 2x/day of Thyrotab. The vet increased it to 1.0, 2x/day for about a month but Gunner went crazy aggressive so he was dropped back down to .8, 2x/day and remained on that for the rest of his life. He then passed away at just over 7 years old due to DCM.

Our heart dog - Gunner

Let's go back to the book for a quick second. So here I was, CRAZY excited that I was helping dogs and literally saving lives. But in the background, I was kicking myself as I never did say how much medication Gunner was on. In fact, I contemplated editing the book so as people would know how much medication their dog should be on as I was told it was based on the weight of the dog.

Then that Face Book post came up. It was obvious, to me, that I saved my dog from euthanasia only to kill him with DCM because he was on too high a medication. I cannot explain the grief all over again! From that day to now, I always have carried that - I killed my beloved Gunner. I feel that and I believe it.

So now my focus changed, or maybe, expanded. My NEW focus was not only bringing attention to Hypothyroidism but to the DANGERS of over medicating which is done REGULARLY. Being honest though, I only had two HUMAN scientific studies that did the correlation of Hypothyroidism to DCM... There are MANY people out there who still don't believe there is a correlation and that medication levels don't have a significant effect.

Well now I have what looks to be proof, but I ask you to be the judge.

Dobermans are rated in the top ten breeds for having TWO significant health issues. One being heart issues and the other being Hypothyroidism. Holter monitors are a test to see heart activity.

Let's go back to Tina.

Because Tina is a reputable breeder - she health tests her dogs regularly. Tina even has her own Holter Monitor and tests her Dobermans for heart issues yearly. This is a "vest" of sorts that she puts on the dog for 24 hours and it records the dog's heart activity. She then takes it to the vet for interpretation and it spits out a fancy report on the dogs heart and everything that occurred over that 24 hour period.

The dog in question and the results: Tina supplied me with four test results for the same dog - a female Doberman.

  1. Before any Hypothyroidism medication

  2. 1 result after being on .6, 2x/day

  3. 1 result after being dropped to .5, 2x/day

  4. 1 result, a few months later - but still on .5, 2x/day

Please note: When reviewing the results, you'll see that the dog's sex changes - I asked Tina and she stated it was an error and it was the same dog. Given our relationship, I do verily believe this to be a true statement. Tina has no reason to lie.



Test Result 2 - September 10, 2018: .6, 2X/DAY MEDS FOR HYPOTYHROIDISM


Test Result 3 - December 28, 2018: .6, 2X/DAY MEDS FOR HYPOTYHROIDISM


Test Result 4 - June 17, 2019: Test check .5, 2X/DAY MEDS FOR HYPOTYHROIDISM

I'm not a vet but I'm thinking that this is significant. No matter what you DID believe, I think you now have enough to recognize the importance of CORRECT DOSAGE and you might even see the possible correlation now.

When I look at these test results, I notice, and bring to your attention, a few key points of interest:

  • The first test, before thyroid medication started, states "Ventricular - not present".

  • The second test, while on .6, 2x/day of Thyrotab, there is significant change in Ventricular Ectopy - a total of 5015.

  • The third test, while dropped to .5, 2x/day of Thyrotab, shows Ventricular Ectopy with a total of 6.

  • The forth test, maintaining on .5, 2x/day of Thyrotab, shows Ventricular Ectopy with now even less at 3.

Please, I never ask you believe me - but I ALWAYS ask you do your own due diligence! These results, to me, are significant and do at least raise questions on the impact that a dog being placed on too high a medication can have in regards to heart issues.

Sadly, I look at these tests and I do have to wonder - what would Gunner's tests have shown? Was his heart literally pounding out of his chest for the following 4 years after he was finally diagnosed until it simply stopped? I think so... I never did do Holter monitors.

I mentioned before that Dobermans are in the top ten for breeds that can have TWO major health issues: Heart issues (DCM) and Hypothyroidism. I'm in many Doberman groups and constantly see Dobermans dropping dead (heart), or suffering from a litany of health issues (un-diagnosed Hypothyroidism). Would this change if we tested immediately for Hypothyroidism and treated properly?

Is there a correlation between Hypothyroidism and DCM?

What I can tell you is this - I see COUNTLESS dogs of ALL breeds suffering with Hypothyroidism because the symptoms (over 70) are not noticed. When they are, many people have to FIGHT for the testing. Many then do the incorrect in house T4 basic test which is proven to not correctly diagnose the dog. Then, if the dog comes back "low but within normal range", the dog is said to be "fine" and not require medication which ALSO is false. Then, when you've passed ALL of those hurdles, the dog is put on too high of a dosage.

For more information on Hypothyroidism PLEASE consider taking the Blaze Challenge! Because of all the information I learned from so many sources - I put together another very short read in my Side Eye series called "By The Numbers". IT'S FREE!

Vol 4 - By The Numbers is what I call "A crash course in Canine Hypothyroidism". It's a 72 page, full colour, dog humor book. The first 50 pages are jokes and cute pictures of dogs (all breeds) - all of which are Hypothyroid and from the Face Book group "Hypothyroidism in Dogs". The remaining 20 pages are all the information you need to learn how to diagnose, treat and advocate for your dog! I have said I'm not a vet, and I'm not, but all information in that book also has the supporting documentation from Dr. Jean Dodds, DVM. I also include the full Q&A interview I had with Dr. Dodds. This is VITAL information for you to advocate for your dog.

FREE DOWNLOAD CAN BE FOUND HERE (bottom of the page):

Please consider it. Now, let's have the discussion...

Be safe and well! Karen Grzenda, Author Find all my books on Amazon in EBook or Paperback! Heart Dog – Gunner’s Story (true life novel): The Side Eye Series (adult series): Little Paws (children’s series):

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