Page 312 - Feline Cardiology

320 Section H: Arterial Thromboembolism

resting respiratory rate. An increase in rate or effort ible loss of limb viability and necrosis requires amputa-
should prompt a reexamination and thoracic radio- tion as an alternative to euthanasia. Although the risk of
graphs to screen for CHF. The recommended coagula- future thromboembolic events is not altered, some cats
tion profile testing is dependent on the treatment being will have good quality of life following amputation.
used and is discussed with the specific medications Other cats sustain permanent flexure of their metatarsus
above. secondary to severe atrophy of their cranial tibial muscle
group. In the University of Minnesota’s large retrospec-
tive study, although the presence of CHF did not effect
LONG-TERM OUTCOME AND PROGNOSIS
survival to discharge, cats with CHF at presentation had
Although the diagnosis of cardiogenic ATE carries a a median survival of 77 days compared to cats without
poor prognosis, it is important to keep in mind that CHF at presentation, in which the median survival was
treating these patients can still be fulfilling and may 254 days. Thus, it appears the underlying heart disease
result in good quality of life for an extended period of is the most common cause of death. This hypothesis is
time. Otherwise, the outcome for a disease such as ATE corroborated by the fact that only 20% of the cats died
can be a self fulfilling prophecy with owners encouraged or were euthanized due to recurrent ATE (Smith et al.
to elect euthanasia (due to poor survival statistics) result- 2003). Similarly, in another study, which included 57
ing in a further reduction in survival statistics. The cats at risk for ATE, of the 30 deaths or euthanasias, the
short-term prognosis depends largely on the nature and majority were due to CHF (12) while only 4 were sec-
ondary to recurrence of ATE (Smith et al. 2004).
responsiveness of the underlying heart disease and heart
Arterial Thromboembolism poor survival times for cats with ATE (Rush et al. 2002; REFERENCES
failure. Most older studies have suggested extremely
Laste and Harpster 1995; Moore et al. 2000). However,
Boldface font indicates key references.
most of these reports did not distinguish between eutha-
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bias (Smith and Tobias 2004). In one study that attempted
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45% when cats that did not receive therapy were excluded. hypertrophic cardiomyopathy: 74 cases (1985–1989). J Am Vet
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Moreover, survival over the course of the 9-year study Bedard C, Lanevschi-Pietersma A, Dunn M. Evaluation of coagula-
improved over time, with a discharge rate of 73% in the tion markers in the plasma of healthy cats and cats with asymp-
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Findings that conferred a better survival rate were 167–172.
having a single limb rather than bilateral limb involve- Behrend EN, Grauer GF, Greco DS, Rose BJ, Thrall MAH. Comparison
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