Page 730 - Small Animal Clinical Nutrition 5th Edition

Cardiovascular Disease 757

lymph flow through the thoracic duct in human patients with ENDNOTES
VetBooks.ir chylothorax and can be used in feline and canine patients a. Pipers F. Merial U.S. Personal communication. 2002.
(Chapter 26).No clinical trials to evaluate the efficacy of parenter-
al nutrition in patients with chylothorax have been reported.
In the past, feeding a low-fat homemade or commercial food b. Metabolic Analysis Lab, Inc., 1202 Ann Street, Madison,
supplemented with medium-chain triglycerides was recom- WI, USA.
mended for patients with chylothorax because it was thought to c. Shelton GD. Director, Comparative Neuromuscular Labor-
minimize thoracic duct flow. However, newer information atory, School of Medicine, University of California-San
challenged this concept and showed that thoracic duct flow Diego, LaJolla, CA, USA.
may not be altered significantly by nutritional changes in dogs d. Pimobendan. (Vetmedin). Boehringer Ingelheim, USA.
(Sikkema et al, 1993). Until more information is available, the
primary management goals for chylothorax should be to meet
the overall nutritional needs of the patient rather than focusing REFERENCES
on nutritional changes designed to reduce chyle production. In
most patients, medical and nutritional management are usually The references for Chapter 36 can be found at
temporary means to support the patient until surgery (Birchard www.markmorris.org.
et al, 1988; Fossum et al, 1991). Fewer than 20% of cats with
idiopathic chylothorax respond to long-term medical and
nutritional management alone (Fossum et al, 1991).

CASE 36-1

Congestive Heart Failure in a Beagle Crossbred Dog
Bruce W. Keene, DVM, Dipl. ACVIM (Cardiology)
College of Veterinary Medicine
North Carolina State University
Raleigh, North Carolina, USA

Patient Assessment
An 11-year-old, neutered female beagle crossbred dog weighing 10 kg was admitted to the hospital with a three-month history of
weight loss and reduced appetite. The patient had been short of breath for the past 24 hours and would not lie down the previous
night.The dog had been examined by a veterinarian two months earlier for coughing and exercise intolerance. At that time a tenta-
tive diagnosis of tracheobronchitis was made and the patient was treated with a trimethoprim-sulfadiazine combination for seven
days and a sustained-release theophylline compound for three weeks. Clinical signs improved some during the first week of therapy.
The dog’s vaccinations were current. Yearly heartworm antigen tests were negative for the past five years. The patient received
ivermectin monthly for heartworm prevention, and except for intermittent flea problems and mild periodontal disease, had been
exceptionally healthy its entire life.
º
º
On presentation, the dog’s rectal temperature was 38.9 C (102.1 F), the pulse 160/min. and the respiratory rate 70/min. The
patient appeared alert and anxious, with rapid, labored breathing. Mucous membranes were pale pink and the capillary refill time
was slightly slow. A modest amount of periodontal disease and dental calculus was noted.
The bronchovesicular sounds were louder than normal and end-inspiratory crackles were heard diffusely over the lung fields bilat-
erally, accompanied by some expiratory wheezes.The precordial impulse was normally located and the arterial pulses were rapid but
regular. A 3/6 holosystolic (regurgitant quality) murmur heard best at the left cardiac apex and radiating somewhat to the heart base
was auscultated. A softer, regurgitant quality systolic murmur was audible at the right hemithorax. The jugular veins were modest-
ly distended and a systolic jugular venous pulse was present. The abdomen was nonpainful. The liver was descended about 2 cm
below the costal arch. Body condition score was 2/5. The rest of the physical examination was unremarkable.
Results of the initial laboratory tests included: complete blood count (normal); urinalysis (urine specific gravity = 1.022 [refer-
ence range = 1.001 to 1.070], dipstick and sediment examination were normal); and serum biochemistry profile (normal, except for
a mild elevation in serum creatinine concentration). Generalized cardiomegaly with especially prominent left atrial and left ventric-
ular enlargement was evident radiographically. Pulmonary venous distention and air bronchograms typical of cardiogenic pul-
monary edema were also visualized (Figures 1A and 1B).
The clinical diagnosis was congestive heart failure (CHF) secondary to chronic valvular heart disease (endocardiosis) and
mitral/tricuspid regurgitation.