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Figure 1 (A) Cardiac sarcoidosis characterized by coalescence of granulomatous elements along lymphatic pathways of the myocardial interstitium (H&E x 60). (B) High-power magnification showing well-formed nonnecrotizing granulomas composed of epithelioid histiocytes and giant cells embedded in callagenous stroma. Mononuclear inflammatory cells and fibroblasts surround the granulomas (H&E x 400). (C) Idiopathic giant cell myocarditis (IGCM) showing widespread necrosis of myocytes by a dense cellular infiltrate (H&E x 100). (D) High-power magnification of IGCM displaying giant cells, lymphocytes, histiocytes, eosinophils, and damaged myocytes (H&E x 400).