Objective—To determine current population characteristics
of, clinical findings in, and survival times for
cats with hypertrophic cardiomyopathy (HCM).
Animals—260 cats with HCM.
Procedure—Information was obtained from the medical
records. Cats were classified into 1 of 4 clinical
groups (congestive heart failure [CHF] group, arterial
thromboembolism [ATE] group, syncope group, or
cats without clinical signs [subclinical group]) on the
basis of the primary clinical signs at the initial examination.
Results—120 cats were classified in the CHF group,
43 in the ATE group, 10 in the syncope group, and 87
in the subclinical group. Antecedent events that may
have precipitated CHF included IV fluid administration,
anesthesia, surgery, and recent corticosteroid
administration. Median survival time was 709 days
(range, 2 to 4,418 days) for cats that survived > 24
hours. Cats in the subclinical group lived the longest
(median survival time, 1,129 days; range, 2 to 3,778
days), followed by cats in the syncope group (654
days; range, 28 to 1,505 days), cats in the CHF group
(563 days; range, 2 to 4,418 days), and cats in the ATE
group (184 days; range, 2 to 2,278 days). Causes of
death included ATE (n = 56), CHF (49), sudden death
(13), and noncardiac causes (27). In univariate analyses,
survival time was negatively correlated with left
atrial size, age, right ventricular enlargement, and thoracentesis.
Cats with systolic anterior motion of the
mitral valve lived longer than cats without this
echocardiographic finding. In multivariate analyses,
only age and left atrial size remained significant predictors
of survival time.
Conclusions and Clinical Relevance—Although
overall survival time for cats with HCM was similar to
earlier reports, survival times for cats with CHF or
ATE were longer than previously reported. (J Am Vet
Med Assoc 2002;220:202–207)