The heart showed mild hypertrophy of the left ventricle, and severe dilation of the right ventricle. The right atrium and right ventricle had patchy fatty infiltration into the cardiac wall (Figs. 2, 3, 4). The right atrium showed a greater degree of the fatty infiltration than the right ventricle. The endocardium was thin and translucent. The heart valves were predominantly thin and pliable without vegetations. The chordae tendineae of the tricuspid valve were elongated and attenuated.
Sections of the right atrium and right ventricle (Figs. 5, 6, 7, 8, 9) showed fatty infiltration and fibrosis with variation in the size of myocyte fibers (atrophy) and vacuolization of myocytes. Sections of the left ventricle (Figs. 10, 11, 12) and left atrium showed similar changes, but to a lesser degree. An organizing mural thrombus was seen in the right atrial appendage. There was greater than 75% narrowing of the left anterior descending coronary artery and greater than 95% narrowing of the left circumflex coronary artery by atherosclerotic plaque.
Fig 2. Gross image of right atrium and right ventricle.
Fig 3. Gross image of right atrium.
Fig 4. Gross image of right ventricle.
Fig 5. Right atrium, H&E stain (40x).
Fig 6. Right atrium, H&E stain (200x).
Fig 7. Right ventricle, H&E stain (20x).
Fig 8. Right ventricle, H&E stain (400x).
Fig 9. Right ventricle, trichrome stain (100x).
Fig 10 -11. Left ventricle, H&E stain (100x).
Fig 12. Left ventricle, H&E stain (200x).