Abstract
Background:Management of cardiac amyloidosis (CA) is related to amyloid deposition. Our aim was to assess the effect of amyloid deposition on myocardial function.
Methods and Results:Twenty-eight patients with transthyretin mutation and a group of 14 controls underwent echocardiography to quantify left ventricular (LV) dimensions, function, and global (G) longitudinal (L), radial (R) and circumferential (C) strain (S). 99mTc-3,3-diphosphono-1,2-propanodicarboxylic-acid-scintigraphy (99mTc-DPD) was used to quantify CA. 99mTc-DPD revealed accumulation in 14/28 patients (CA group) and no accumulation (no-CA group) in 14. Cardiac accumulation was lower-than-bone uptake in 5 (mild-CA group) and higher-than-bone uptake in 9 (severe-CA group). Ejection fraction was similar among groups. GLS was lower (P<0.001) in the severe-CA group (−12.2±4.5) with respect to the no-CA group (−19.3±3.0) and to the control group (−20.9±2.5). Conversely, GCS and GRS were lower (P<0.05) in the mild-CA group (−10.8±4.1 and 9.5±5.7, respectively) with respect to the severe-CA group (−18.9±5.1 and 23.9±6.3 respectively), no-CA group (−19.2±4.1 and 28.4±10.2, respectively) and the control group (−23.9±4.4 and 29.9±8.7, respectively). A correlation was found between the scintigraphic heart retention index (HRI) and LV septal thickness (ρ=0.72), E/E’ (ρ=0.46) and GLS (ρ=−0.40).
Conclusions:Myocardial deformation is impaired in a different stage of CA. The 99mTc-DPD HRI correlated well with morphologic, diastolic and strain abnormalities. (Circ J 2016; 80: 1998–2003)
