Relative apical sparing of longitudinal strain using two-dimensional speckle-tracking echocardiography is both sensitive and specific for the diagnosis of cardiac amyloidosis.

Background: The diagnosis of cardiac amyloidosis (CA) is challenging owing to vague symptomatology and nonspecific echocardiographic findings. Objective: To describe regional patterns in longitudinal strain (LS) using two-dimensional speckle-tracking echocardiography in CA and to test the hypothesis that regional differences would help differentiate CA from other causes of increased left ventricular (LV) wall thickness. Methods: and results 55 consecutive patients with CA were compared with 30 control patients with LV hypertrophy (n¼15 with hypertrophic cardiomyopathy, n¼15 with aortic stenosis). A relative apical LS of 1.0, defined using the equation (average apical LS/(average basal LS + mid-LS)), was sensitive (93%) and specific (82%) in differentiating CA from controls (area under the curve 0.94). In a logistic regression multivariate analysis, relative apical LS was the only parameter predictive of CA (p¼0.004). Conclusions CA is characterised by regional variations in LS from base to apex. A relative 'apical sparing' pattern of LS is an easily recognisable, accurate and reproducible method of differentiating CA from other causes of LV hypertrophy. [ABSTRACT FROM AUTHOR]