Restrictive cardiomyopathy

Question 1

What are the characteristics of restricted cardiomyopathy

Answer 1

RCM is characterized by impaired diastolic filling (as indicated by an often massively dilated left, and occasionally right atrium), where the left ventricle has minimal signs of hypertrophy or systolic dysfunction
- it is thought to be that the left (+/- right) ventricle is stiff and non-compliant because of fibrous, rather than hypertrophic change

Question 2

What is the typical presentation for cats with RCM

Answer 2

Cats with RCM usually present with signs of congestive heart failure (e.g., dyspnoea)

Question 3

What are the typical echocardiographic findings

Answer 3

The hallmark 2D features of the myocardial form are grossly normal-apperaing LV (structurally normal and functionally normal in systole) with a large LA
- a severely enlarged LA (LA/Ao > 2) is common and confers a poor prognosis

Patchy endomyocardial fibrosis is sometimes observed (endomyocardial form) which may obliterate the distal portions of the LV chamber

Question 4

What kind of electrocardiographic abnormalities are common with RCM

Answer 4

Supraventricular tachyarrhytmias and ventricular arrhythmias are frequent with RCM