Page 185 - Feline Cardiology

186 Section D: Cardiomyopathies

TREATMENT After the initial diagnosis is made, periodic reevalua­
tion could include physical examination (heart rate and
Given that cats with dilated cardiomyopathy may be respiratory rate), radiographs (for evidence of heart
taurine­deficient, taurine supplementation should failure), and blood pressure monitoring (for hypoten­
always be given until the taurine levels have been proven sion). A renal profile to monitor BUN, creatinine, and
to be normal. Supplementation should be provided at electrolytes is also helpful to monitor for complications
250 mg orally twice day and can typically be purchased associated with therapy. Recheck echocardiography may
by the owner at a health food store. be needed only if an acute change occurs (sudden
A positive inotrope to aid the decreased systolic dys­ decompensation to heart failure, development of signs
function should be provided. Digoxin, 0.03125 mg of thromboembolic disease).
(1/4 of a 0.125 mg tablet PO q 48 hours) can be used.
Cardiomyopathies Pimobendan, a stronger positive inotrope, appears to be OUTCOME AND PROGNOSIS
well tolerated in the cat at a dose of 1.25 mg orally twice
a day. At least in the dog, pimobendan also appears to
The prognosis for cats with dilated cardiomyopathy is
have other positive effects, including increased appetite,
that may be beneficial in a cat with heart failure. However,
a more gradual progression. In many cats, if taurine
pimobendan is not approved for use in the cat in varied. Some cats progress very rapidly, and others have
the United States and use of this drug in cats should be deficiency is identified and treated before severe heart
supported by client understanding and consent for off­ failure has developed the disease will begin to reverse.
label use. Cats that are successfully treated and survive the first 30
Treatment should include additional medications, days have an excellent chance of survival (Pion et al.
including furosemide and an ACE inhibitor, as needed 1992). Substantial improvement in a cat’s attitude and
for the symptoms associated with congestive heart appetite is often observed even within the first few weeks
failure if it is present (see Chapter 19). of treatment (Pion et al. 1992).
Thoracocentesis and/or abdominocentsis should In general, prognosis is poor unless taurine deficiency
be performed if pleural effusion or ascites is having is present.
an effect on respiration (see Chapter 3).
If atrial fibrillation or an atrial tachycardia is observed, REFERENCES
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COMPLICATIONS AND MONITORING
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