Case 1

Signalment

• 7 year old
• Male neutered
• Domestic short haired cat

History

• Fully vaccinated
• Sudden death at home
• No other clinical abnormalities

Gross Pathology

Hypertrophic cardiomyopathy (cat). Courtesy of T. Scase

The following data and pictures were taken at post-mortem examination:

Cardiovascular system:

• Heart has a globoid shape
• Ventricular wall measurements:
  • Interventricular septum; 12mm

Hypertrophic cardiomyopathy (cat). Courtesy of T. Scase

**Right ventricular wall; 3mm

• • Left ventricular wall; 10mm
• Pericardium is fatty, shiny and intact

No embolic thrombi were found in the abdominal aorta.

The other body systems were examined.
No further abnormalities were found.

Histopathology

Histology; hypertrophic cardiomyopathy. Courtesy of K. Hughes

Samples were taken for histological examination (Stained with H and E):

• The cardiac myocytes are multifocally widely spaced and infiltrated by streams of spindle shaped cells (fibroblasts).

Some sections were stained with Massons Trichrome:

Histology; Massons Trichrome. Courtesy of K. Hughes

• This confirmed the presence of large, multifocal areas of fibrosis within the inner third of the myocardium and extending to the endocardial surface.
• Multifocally the fibrosis surrounds individual atrophied myocytes.
• There is mural thickening (smooth muscle hypertrophy) of the intramyocardial arteries.