Pulse - March 2023 - 14

UC DAVIS UPDATE
First Time Surgery Gives New Hope for
Dog with Complicated Megaesophagus
Rob Warren, UC Davis VMTH Communications & Marketing Officer
G
inger, a 13-year-old Belgian
Malinois, was first
diagnosed with megaesophagus
seven years ago when she
presented to the UC Davis veterinary
hospital with severe
weakness from myasthenia
gravis. With aggressive medical
treatment, the hospital's Neurology
and Neurosurgery Service
supported Ginger back to health
and her myasthenia gravis went
into remission. However, the
megaesophagus persisted until
it became life-threatening.
Megaesophagus is a challenging disorder to
manage, and the journey can be long and arduous.
Thankfully for Ginger, she has a dedicated
family and a compassionate medical care team
diligently working to improve her quality of
life. Refusing to give up hope, her team trialed
several innovative medical and therapeutic
procedures before opting for a surgery never
performed at UC Davis that ended up saving
Ginger's life.
By December 2020, Ginger was experiencing
painful regurgitation episodes with every
meal, and she had lost more than 15 pounds at
which point she was presented to the Internal
Medicine Service. A videoendoscope showed
significant inflammation of the esophagus,
and a swallow fluoroscopic study, followed by
an esophageal catheter pressure study, showed
that her lower esophageal sphincter was not
relaxing properly to permit passage of ingesta
into the stomach.
She was diagnosed with esophageal achalasia-like
syndrome, a disorder that is well characterized
in humans but is far less characterized
in the dog. A stomach feeding tube was
placed in Ginger to temporarily circumvent
the dilated esophagus while her extensive care
team started a series of medical treatments and
procedures to treat the condition.
A series of treatments targeted at reducing
14
Ginger's complicated case of megaesophagus progressed to malnutrition and was becoming life
threatening until a first-time procedure at UC Davis saved her.
the pressure in the restricted lower esophageal
sphincter were attempted. First, sildenafil
was used to relax the sphincter, but
minimal response was seen. Next, balloon
dilation and botox injections of the lower
esophageal sphincter were attempted to open
and relax her lower esophageal sphincter.
Despite these efforts, the sphincter remained
abnormally constricted.
In humans that do not respond to these interventions,
the next option is a surgical procedure
to help open the sphincter. Consults
were sought from the UC Davis School of
Medicine and Sutter Health esophagologists
and surgeons to better understand the surgical
approach, and by July 2021, Ginger became
the first UC Davis veterinary patient to ever
have the esophageal procedure.
Ginger's surgery involved a myotomy, which
involves cutting through the musculature of
the lower esophageal sphincter, and also a fundoplication,
which involves partially wrapping
the stomach around the lower portion of the
esophagus and lower esophageal sphincter to
reinforce the connection of the esophagus and
stomach. The fundoplication step was necessary
to prevent overrelaxation of the lower
esophageal sphincter, which could have caused
more reflux and regurgitation.
This technique has only been performed in
a handful of dogs with conditions similar to
Ginger's and therefore the long-term rate of
success is not known. For Ginger, the surgery
combined with sildenafil treatment to relax the
sphincter has been a remarkable success. She
is now able to eat a liquid diet by mouth when
fed upright, and she remains well controlled 18
months post-surgery.
There is still much more to be learned about
esophageal achalasia-like syndrome and megaesophagus
in dogs. UC Davis has launched
ongoing clinical trials to better understand,
characterize, and treat megaesophagus and
other similar disorders in dogs. To learn more,
visit the UC Davis Veterinary Center for
Clinical Trials website at clinicaltrials.vetmed.
ucdavis.edu. P
MARCH 2023
PULSE

http://www.clinicaltrials.vetmed.ucdavis.edu http://www.clinicaltrials.vetmed.ucdavis.edu

Pulse - March 2023

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