Heart and vessels

Question 1

Multiple branching fronds of paucicellular, avascular fibroelastic tissue lined by a single layer of endocardium

Answer 1

Papillary fibroelastoma

Plan:
Correlate with clinical/radiological features
This is a morphological diagnosis of a benign lesion - no specific further action required

Question 2

Polygonal (lepidic) cells within a myxoid stroma form cords, nests, and rings around blood vessels. Hemorrhage, calcifications and lymphoid infiltrates are abundant. May show Gamna-Gandy bodies.

Answer 2

Cardiac myxoma

Plan:
Correlate with clinical and radiological history (?cardiac tumour ?familial syndrome)
Examine further blocks (e.g. for size, completeness of excision)
IPX: Not required for diagnosis
Advice to clinician: May be sporadic or assiociated with Carney complex. Clinical correlation is required.

Question 3

Heart muscle with multiple non-necrotising granulomata, with foreign body giant cells. Giant cells may contain Schaumann or Asteroid bodies

Answer 3

Cardiac sarcoidosis

Differential diagnosis:
Giant cell myocarditis
Fungal/mycobacterial infection
Foreign body granulomas

Plan:
Correlate with clinical history (?cardiomyopathy ?systemic/pulmonary sarcoidosis)
Correlate with any concurrent microbiological testing
Special stains: GMS, PAS, ZN (to evalulate infectious aetiology)
Examine under polarised light

Question 3

Name of calcified collagen fibres in cardiac myxoma

Answer 3

Gandy-Gamna bodies

Question 4

Inflammation of a vessel with lymphocytic and histiocytic infiltrate and giant cells which disrupt the internal elastic lamina.

Answer 4

Giant cell / temporal arteritis

Plan:
Correlate with clinical history / radiologic findings (?sudden onset headache ?raised ESR/CRP)
Examine deeper levels
Special stains: Elastic stain (highlight fragmentation of internal elastic lamina)
Advice to clinician (urgent via phone) - potentially vision threatening diagnosis, patient required urgent corticosteroid treatment

Question 5

Cardiac muscle with coagulative necrosis (loss of nuclear detail), contraction bands (thick eosinophilic bands in myocytes), inflammatory infiltrate

Answer 5

Myocardial infarction

Plan:
Correlate with clinical history / radiologic findings (?chest pain/sudden cardiac death ?troponin rise ?ECG / angiogram)
Examine further sections (to evaluate extent of infarction, complications such as thrombus, aneurysm)