M-mode and two-dimensional echocardiographic features in cardiac amyloidosis.

Twenty-eight patients with cardiac amyloidosis were studied by echocardiography -- 26 by M-mode and 13 by two-dimensional (2D) studies. All had heart failure and biopsy-proved amyloidosis, M-mode features included (1) normal left ventricular (LV) dimension in all; (2) thickened ventricular septum (88%), LV posterior wall (77%), and right ventricular (RV) anterior wall (79%); (3) decreased thickening of ventricular septum (96%) and of LV posterior wall (65%) and reduced LV global function (62%); (4) left atrial enlargement (50%); and (5) pericardial effusion (58%). Two-dimensional echocardiography provided additional features: (1) thickened papillary muscles (five of 13); (2) thickened valves (four of 13); (3) better appreciation of thickened RV wall; and (4) a characteristic "granular sparkling" appearance of thickened cardiac walls -- presumably secondary to the amyloid deposit -- which was noted in 12 of 13 patients. Thus, M-mode echocardiography is helpful in the recognition of cardiac amyloidosis. However, the better appreciation with 2D echocardiography of thickened cardiac walls with a "granular sparkling" appearance in patients with unexplained cardiac failure is virtually diagnostic of cardiac amyloidosis.