A 7-year-old 4.7-kg (10.3-lb) neutered male Russian Blue cat was examined by the referring veterinarian because of lethargy and inappetence of 2 days' duration. Cardiac auscultation revealed the only abnormality identified during physical examination, which was an irregular cardiac rhythm with a frequency of approximately 300 beats/min and interrupted with periods of distinctly lower (albeit undocumented) frequency. The cat had no history of cardiac abnormalities. The cat was immediately referred to the emergency service of a veterinary teaching hospital.
At the referral evaluation, the cat was bright, alert, and responsive and had a body condition score of 5/9. No signs
Objective—To evaluate the use of simultaneous fluoroscopic and transthoracic echocardiographic guidance during transarterial coil placement for embolization of patent ductus arteriosus (PDA) in dogs.
Animals—3 dogs with PDA.
Procedure—Each dog was anesthetized, and a femoral artery was exposed for vascular access. By use of an introducer, a catheter was placed in the thoracic portion of the descending aorta with fluoroscopic guidance, and subsequently, a bolus of iodinated radiographic contrast material was injected to outline the ductus. Under fluoroscopic guidance, 1 coil was positioned in the ductus, but not released. Transthoracic echocardiography was used to ensure that 1 loop of the coil was located in the pulmonary artery. When > 1 loop or no loops were detected in the pulmonary artery, the coil was retrieved and repositioned; when 1 loop of the coil was detected in the pulmonary artery, the coil was detached. After catheter removal, the femoral artery was ligated and the wound was closed.
Results—In all 3 dogs, successful embolization of the PDA was achieved. Echocardiography prevented unintentional pulmonary artery embolization in 1 dog and suboptimal coil placement in the other 2 dogs.
Conclusions and Clinical Relevance—In addition to fluoroscopic control, transthoracic echocardiography appears to aid the appropriate positioning of a transarterial coil for treatment of PDA in dogs. Although transesophageal echocardiography would likely provide better images of the ductus, transthoracic echocardiography is a much cheaper, less specialized, and more widely available alternative.
Objective—To determine portal hemodynamic
changes associated with surgical shunt ligation and
establish ultrasonographic criteria for determining the
optimal degree of shunt narrowing and predicting outcome.
Animals—17 dogs, each with a single congenital
extrahepatic portosystemic shunt.
Procedure—Pre- and postligation flow velocities and
flow directions were determined by Doppler ultrasonography
intraoperatively in the shunt and in the portal
vein cranial and caudal to the shunt origin. Outcome
was evaluated 1 month after surgery by measuring
blood ammonia concentration and performing abdominal
Results—Hepatofugal flow was detected in 9 of 17
dogs before shunt attenuation in the portal segment
that was between the shunt origin and the entering
point of the gastroduodenal vein. If hepatofugal flow
became hepatopetal after shunt ligation, hyperammonemia
resolved. Hepatofugal portal flow was
caused by blood that flowed from the gastroduodenal
vein toward the shunt. Shunt attenuation converted
hepatofugal flow to hepatopetal in the shunt in 12 of
17 dogs. Chronic portal hypertension developed or
perioperative death occurred when the portal congestion
index caudal to the shunt origin increased by
> 3.6 times.
Conclusions and Clinical Relevance—After hepatopetal
flow in the cranial portal vein and the shunt is
established, further shunt narrowing is contraindicated.
Increase of the portal congestion index caudal to the
shunt > 3.5 times should be avoided. Poor outcome
because of severe hypoplasia of the portal branches can
be expected if the flow direction remains hepatofugal
after shunt occlusion cranial to the shunt origin. ( J Am
Vet Med Assoc 2004;224:395–402)
Objective—To determine ultrasonographic abnormalities
in dogs with hyperammonemia.
Animals—90 client-owned dogs with hyperammonemia.
Procedure—Ultrasonography of the abdominal vessels
and organs was performed in a systematic way.
Dogs in which the ultrasonographic diagnosis was a
congenital portosystemic shunt were included only if
they underwent laparotomy or necropsy. Dogs in
which the abdominal vasculature appeared normal
and dogs in which the ultrasonographic diagnosis was
acquired portosystemic shunts and portal hypertension
were included only if liver biopsy specimens
were submitted for histologic examination.
Results—Ultrasonography excluded portosystemic
shunting in 11 dogs. Acquired portosystemic shunts
were found in 17 dogs, of which 3 had arterioportal
fistulae and 14 had other hepatic abnormalities.
Congenital portosystemic shunts were found in 61
dogs, of which 19 had intrahepatic shunts and 42 had
extrahepatic shunts. Intrahepatic shunts originated
from the left portal branch in 14 dogs and the right
portal branch in 5. Extrahepatic shunts originated
from the splenic vein, the right gastric vein, or both
and entered the caudal vena cava or the thorax.
Ultrasonography revealed splenic-caval shunts in 24
dogs, right gastric-caval shunts in 9 dogs, splenic-azygos
shunts in 8 dogs, and a right gastric-azygos shunt
in 1 dog.
Conclusions and Clinical Relevance—Results suggest
that ultrasonography is a reliable diagnostic
method to noninvasively characterize the underlying
disease in dogs with hyperammonemia. A dilated left
testicular or ovarian vein was a reliable indicator of
acquired portosystemic shunts. (J Am Vet Med Assoc