Fig. 3

Images of Case 3. A Transthoracic echocardiogram showed mild left ventricular hypertrophy and sigmoid septum showing significant left ventricular outflow tract obstruction, with concomitant low gradient aortic stenosis. Cardiac magnetic resonance also showed asymmetric septal hypertrophy (septum thickness 15 mm) with no significant late gadolinium enhancement. B Preoperative right ventricular endomyocardial biopsy showed no significant amyloid deposits in the myocardium, except for transthyretin amyloid deposits on the vessel walls of small arteries confirmed by Congo red staining with apple-green birefringence under polarized light microscopy and immunohistochemical staining for transthyretin (asterisks). C Pathology of the resected aortic valve showed patchy amyloid deposits confirmed by Congo red staining with apple-green birefringence under polarized light microscopy and immunohistochemical staining positive for transthyretin. D Pathology of resected myocardium from subaortic septal myectomy showed no significant amyloid deposits in the myocardium, except for transthyretin amyloid deposits on the vessel walls of small arteries confirmed by Congo red staining and immunohistochemical staining for transthyretin