Hypertrophic cardiomyopathy usually affects cats. The overall cardiac dysfunction associated with hypertrophic cardiomyopathy relates to a decrease in diastolic function. Anesthetic regimens that minimize increases in heart rate and stress-related catecholamine release are desirable. Patients with dilative cardiomyopathy can present asymptomatic or in congestive heart failure. The overall myocardial defect is a depression of systolic function. An anesthetic regimen that minimizes myocardial depression is essential.