Alterations in multi-layer strain in AL amyloidosis

Abstract

Background Cardiac involvement in AL amyloidosis portends a poor prognosis. 2D-speckle tracking echocardiography (2D-STE) strain can identify subclinical cardiac involvement. This study performed multilayer and multiplanar 2D-STE myocardial strain analysis. Methods We compared 75 AL amyloidosis patients to 49 hypertensive patients and 49 healthy controls. Longitudinal strain was obtained from epicardial, mid-myocardial and endocardial layers; segmental strain was measured from mid-myocardial basal, mid and apical segments. Results Global longitudinal strain was reduced in epicardial (−14.3 ± −4.0% vs. −17.4 ± 2.2% vs. −17.5 ± −2.0%, p < .001), mid–myocardial (−16.3 ± −4.5% vs. −19.7 ± 2.5% vs. −19.7 ± −2.2%, p < .001) and endocardial layers (−18.7 ± −4.9% vs. −22.2 ± 3.0% vs. −22.3 ± −2.6%, p < .001) in amyloid patients compared to hypertensive and healthy controls. Segmental strain confirmed significant reduction in basal (−11.2 ± −3.9% vs. −17.6 ± 2.7% vs. −20.9 ± −3.4%, p < .001) and mid (−14.8 ± −4.3% vs. −19.2 ± 2.5% vs. −19.6 ± −2.2%, p < .001) LV segments in the AL amyloid group. Receiver operating curve analysis demonstrated that an optimal cut-off of −16% for basal segmental strain better differentiated AL amyloid from hypertensive group (sensitivity 96%, specificity 70%, AUC 0.93), compared to relative apical sparing (AUC of 0.85). Conclusion Strain demonstrated myocardial involvement in all layers in AL amyloidosis, with reduced basal segmental longitudinal strain a likely marker of early disease.