Magnetic-Resonance-Imaging-Based Left Atrial Strain and Left Atrial Strain Rate as Diagnostic Parameters in Cardiac Amyloidosis

Abstract

Aims: The present study aims to evaluate magnetic-resonance-imaging (MRI)-assessed left atrial strain (LAS) and left atrial strain rate (LASR) as potential parameters for the diagnosis of cardiac amyloidosis (CA), the distinction of clinical subtypes and differentiation from other cardiomyopathies. Methods and results: LAS and LASR were assessed by MRI feature tracking in patients with biopsy-proven CA. LAS and LASR of patients with CA were compared to healthy subjects and patients with hypertrophic cardiomyopathy. LAS and LASR were also analyzed concerning differences between patients with transthyretin (ATTR) and light chain amyloidosis (AL). A total of 44 patients with biopsy-proven CA, 19 patients with hypertrophic cardiomyopathy and 24 healthy subjects were included. In 22 CA patients (50%), histological examination identified ATTR as CA subtype and AL in the remaining patients. No significant difference was observed for reservoir, conduit or booster LAS in patients with AL or ATTR. Reservoir LAS, conduit LAS and booster LAS were significantly reduced in patients with CA and HCM as compared to healthy subjects (p < 0.001). Reservoir LAS and booster LAS were significantly reduced in CA as compared to HCM patients (p < 0.001). A linear correlation was observed between LA global reservoir strain and LA-EF (p < 0.001, r = 0.5), conduit strain and global longitudinal LV strain (p < 0.001, r = 0.5), global booster strain rate and LA-EF (p < 0.001, r = 0.6) and between global booster strain rate and LA area at LVED (p < 0.0001, 0.5). Conclusions: LAS and LASR are severely impaired in patients with CA. The MRI-based assessment of LAS and LASR might allow non-invasive diagnosis and categorization of CA and its distinct differentiation from other hypertrophic phenotypes.

A Machine Learning Challenge: Detection of Cardiac Amyloidosis Based on Bi-Atrial and Right Ventricular Strain and Cardiac Function

“…These morphological differences appear to be associated with greater atrial strain impairment in CA patients compared to HCM patients. The PCA model highlights their importance in disease discrimination, supported by recent studies [ 11 , 13 ]. Moreover, LV-EF and RV-EF remain strong discriminatory diagnostic features for CA differentiation in agreement with recent studies [ 15 , 30 ].…”

“…Moreover, the majority of features in the PCA model were based on left and right atrial strain parameters. Impairment of nearly all functional phases for left and right atrial longitudinal strain appears to be a further valuable discriminative characteristic contributing towards diagnostic accuracy, as previously observed for the left atrium [ 11 ]. Additionally, visual characteristics such as atrial enlargement, interatrial septal thickening and atrial dysfunction are generally associated with CA rather than HCM phenotype [ 14 ].…”

“…The novelty of our study is underscored by the use of multi-chamber strain diagnostics for CA, without incorporation of the left ventricle or contrast agent, which has not been clinically established. Recent studies have substantiated that amyloidotic infiltration of the myocardium exacerbates cardiac deformation at both the atrial [ 11 , 13 ] and ventricular level [ 6 , 15 ]. This allows for anticipation of a unique cardiac strain profile associated with amyloidotic cardiomyopathy.…”

“…However, recent investigations have shown that cardiac strain provides discriminative value for all cardiac chambers and thus may support differentiation of CA from hypertrophic cardiomyopathy (HCM) and healthy control subjects (CTRL) [ 6 , 11 , 12 , 13 , 14 , 15 ]. Based on previous observations [ 11 , 12 , 14 , 15 , 16 ] and in the hope of optimizing CMR diagnostic accuracy for CA detection, we hypothesize that strain measurements of the diagnostically less popular cardiac chambers along with general cardiac functional parameters may achieve a high CA diagnostic accuracy. Cardiac strain parameters would thus solely derive from both atria and the right ventricle.…”

Multi-parametric analyses to investigate dependencies of normal left atrial strain by cardiovascular magnetic resonance feature tracking

“…Clinical utility of MRI-attained LA strain has experienced extensive growth in its diagnostic value. For example, the challenge of distinguishing between hypertrophic cardiomyopathy from cardiac amyloidosis 6 , 26 , 27 or even the differentiation between subtypes of amyloidosis 24 were shown to be facilitated through left atrial strain quantification. The majority of previous studies were performed using echocardiography, whereby MRI data still remains limited and partially inconsistent, particularly regarding specific parameter dependencies (e.g.…”