Quantitative Analysis of Endocardial and Epicardial Left Ventricular Myocardial Deformation in Patients with Cardiac Amyloidosis

Abstract

Background : Studies using cardiovascular magnetic resonance imaging have demonstrated subendocardial deposition of amyloid protein in patients with cardiac amyloidosis (CA). We examined whether subendocardial dysfunction due to amyloid deposition exists in patients with CA.
Methods : We examined 98 consecutive patients with CA and 20 control individuals. CA patients were divided into three groups. Group 1 had no evidence of cardiac involvement (n＝32), group 2 had heart involvement but no congestive heart failure (CHF) and/or serum brain natriuretic peptide (BNP) levels < 100 pg/mL (n＝23), and group 3 had heart involvement and CHF and/or serum BNP levels ≥ 100 pg/mL (n＝43). Circumferential, radial, and longitudinal strains of the inner half and outer half layers of the left ventricular (LV) wall were examined.
Results : There was no significant difference in strain parameters between those with AL and ATTRm amyloidosis. There were no significant differences in circumferential inner/outer strain among the 4 groups. Regarding radial strain, groups 2 and 3 had a depressed inner radial strain compared with group 1 in the entire basal and mid-LV wall (P < 0.001, one-way analysis of variance) and that in group 1 was smaller than that in controls. Longitudinal strains of the inner/outer layers in the basal and mid-LV wall were significantly depressed with apical sparing in groups 2 and 3 compared with those in group 1.
Conclusions : In patients with CA, complete endomyocardial radial systolic dysfunction and longitudinal transmural systolic dysfunction exist in the basal and mid-LV wall.