Page 2062 - Cote clinical veterinary advisor dogs and cats 4th

Vascular Ring Anomaly 1031.e3

TREATMENT

VetBooks.ir Treatment Overview Diseases and Disorders
Esophageal constriction caused by vascular
ring anomalies is treated surgically by ligation
and division of the aberrant vessel(s), with
the ultimate goal being to reduce or eliminate
regurgitation. Intensive preoperative and post-
operative care may be required for debilitated
patients. Consultation with a veterinary surgeon
is advised.
Acute General Treatment
• Young, malnourished animals may benefit
from fluid therapy with dextrose.
• Animals with aspiration pneumonia
require antibiotic therapy before surgical
intervention.
• Surgical division of the vascular ring
A B ○ For the vast majority of vascular ring
anomalies, the preferred surgical approach
VASCULAR RING ANOMALY A, Ventrodorsal thoracic radiograph of a normal dog. B, Ventrodorsal thoracic is a left fourth intercostal thoracotomy.
radiograph of a dog with vascular ring anomaly. Leftward deviation of the trachea (arrow) is characteristic of ○ Ventilation is required after entering the
vascular ring anomaly. thorax, and a thoracostomy tube is placed
before closure to evacuate air.
○ When the vascular ring is caused by PRAA,
the left ligamentum arteriosum is ligated
and divided, releasing the constriction on
the esophagus.
○ When the vascular ring is caused by an
aberrant subclavian artery coursing over
the esophagus, this artery is ligated and
divided. No adverse effects are noted from
this ligation because the vertebral artery
supplies adequate collateral flow.
○ When a double aortic arch is present, the
smaller arch is ligated and divided.
○ Thoracoscopic ligation of a left ligamen-
tum arteriosum (with PRAA) has been
reported as a less invasive surgical
option.

Nutrition/Diet
• Severely malnourished animals may require
nutritional support before surgery, including
elevated feedings of slurried food or place-
ment of a gastrostomy tube.
• Give slurried food to the patient from an
elevated position or by gastrostomy tube
for several weeks after surgery (similar
to megaesophagus). If no regurgitation
occurs, most dogs can be returned to a
VASCULAR RING ANOMALY Three-dimensional volume-rendered CT image of a double aortic arch from a normal feeding regimen 1-2 months after
3-month-old, male, mixed-breed puppy. The left and right aortic arches have persisted to form a ring that encircles surgery.
the trachea and esophagus. Knowledge of the type of vascular anomaly is important for surgical planning.
Possible Complications
Most common complication is aspiration
reliably differentiates dogs with vascular focal dilation of the esophagus that narrows pneumonia. Regurgitation may continue after
ring anomalies from dogs with generalized at the base of the heart. Although this finding surgical disruption of the vascular ring because
megaesophagus. These radiographic find- is diagnostic for a vascular ring anomaly, it of loss of neuromuscular esophageal function.
ings may obviate the need for a barium does not reveal the type of anomaly present Some animals may never be able to ingest solid
esophagram. and is often unnecessary when a working food and may need to be fed a slurry diet
• If evidence of aspiration pneumonia: CBC diagnosis is made from thoracic radiographs. indefinitely.
and further testing as needed • Nonselective CT angiography is increasingly
being used for three-dimensional anatomic Recommended Monitoring
Advanced or Confirmatory Testing reconstruction of the anomalous vasculature Thoracic radiographs should be used for moni-
• Barium esophagram: barium given in food to obtain a specific diagnosis and assist in toring aspiration pneumonia and to document
can be used to radiographically outline the selecting the surgical approach. resolution of megaesophagus.

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