Cardiac Amyloidosis with Normal Wall Thickness: Prevalence, Clinical Characteristics and Outcome in a Retrospective Analysis

Abstract

Background: Cardiac amyloidosis (CA) is a rare, progressive, infiltrative cardiac disease. Light chain (AL) and transthyretin (ATTR) amyloidosis are in the background in almost all cases. New, easily available diagnostic tools and recently introduced novel therapies for both types of CA put this disease into the field of interest. Increased left ventricular wall thickness (IWT) detected by echocardiography is generally thought to be a necessary part of the diagnosis. We aimed to determine the proportion of CA patients without IWT, and to define the clinical characteristics of this cohort. Methods: In an academic tertiary center for CA, we identified patients diagnosed and treated for CA between January 2009 and February 2022. In a retrospective analysis we defined the proportion of patients with (≥12 mm) and without (<12 mm) IWT, and described their clinical features. Results: We identified 98 patients suitable for the analysis. In total, 70 had AL and 27 ATTR CA; 89 patients had CA with IWT and 9 patients (9%) had CA without IWT. All non-IWT patients had AL type CA. Both group of patients had clinically significant disease, which is supported by the relevant elevation in cardiac biomarker levels. There was no difference between the outcome of the two groups. Conclusion: Patients without IWT form a relevant subgroup among those with CA. Our results suggest that diagnostic algorithms and criteria should take these individuals into consideration, and, therefore, give them access to effective treatments.

Deep Learning to Classify AL versus ATTR Cardiac Amyloidosis MR Images

“…CMR features were also suggestive or typical for all included patients (some cases without awaited MR findings despite clinical, biological or echocardiographic suggestive data were excluded from the study). Most important MR features were thickened septum, generally associated with left ventricular mass increase (except for 5 patients with AL CA whose septal thickness was <12 mm, which is concordant with previously reported observation [27]), left/right atrial dilatation, reduced downward systolic excursion of the mitral plane, pericardial or pleural effusion, increased native T1 myocardial relaxation time and extracellular volume (ECV) and typical late gadolinium enhancement of the ventricular ± atrial cardiac walls with inversed myocardial vs blood pool nulling in TI scout Lock-Locker sequences.…”

Echocardiography combined with Mayo staging enhances the identification of early mortality risk in patients with light-chain cardiac amyloidosis

“…左室舒张功能减低在AL-CA患者中十分常见 [16,17] , 并 且严重AL-CA患者可出现左室收缩功能下降. 然而, 尚 未发现E/e′可应用于AL-CA预后判别, 既往研究显示左 室射血分数＜50%在梅奥2012分期IV期基础上未能进 一步提高预测价值 [18] .…”