Transthyretin Cardiac Amyloidosis

This is a first in human study that will assess the safety, pharmacokinetics, biodistribution and diagnostic performance of \[18F\]FIDT-10b (fluorine-18 labeled FIDT-10b), a positron emission tomography (PET) agent. This agent has the potential to specifically identify the involved myocardium of patients with transthyretin cardiac amyloidosis (ATTR-CA).

The goal of this clinical trial is to learn if trimetazidine can improve blood flow in the heart in adults with transthyretin cardiac amyloidosis (ATTR-CM). ATTR-CM is a condition in which an abnormal protein builds up in the heart and can make it harder for the heart to work normally. The main question this study aims to answer is: Does trimetazidine improve the heart's ability to increase its blood flow when more blood is needed? The study will also look at whether treatment is linked to changes in walking ability, heart-related blood tests, heart function, and quality of life. Participants will: Take trimetazidine for about 6 months. Have heart blood flow measured with a positron emission tomography/computed tomography (PET/CT) scan before and after treatment. Have heart ultrasound examinations and blood tests. Complete a 6-minute walk test and a questionnaire about their symptoms and quality of life.

Transthyretin cardiac amyloidosis (ATTR-CM) is an infiltrative cardiomyopathy caused by amyloid fibril deposition, leading to heart failure and arrhythmias. Despite advances in diagnosis, the disease remains commonly unrecognized and presents heterogeneously. Recent therapies targeting transthyretin stabilization and gene silencing have improved outcomes, but current staging systems based on biological and functional markers have limited ability to guide treatment. Imaging techniques such as cardiac magnetic resonance (CMR) provide tissue characterization, but noninvasive molecular imaging of myocardial fibrotic activity remains limited. Positron emission tomography (PET) tracers targeting fibroblast activation protein (FAPI), labeled with gallium-68 (68Ga), offer a promising approach to detect and quantify fibroblast activity associated with myocardial remodeling. This study aims to evaluate \[68Ga\]Ga-FAPI PET imaging for staging ATTR-CM and distinguishing patients with disease progression under therapy. The investigators hypothesize that \[68Ga\]Ga-FAPI uptake reflects fibrotic activity correlating with disease severity and progression. If validated, \[68Ga\]Ga-FAPI PET could serve as a novel biomarker for improved staging and personalized strategies in ATTR-CM.

CONCERTO is a retrospective, observational, multicentric and single-arm study to perform an external validation of the cloud-based and AI-powered electrocardiogram (ECG) analysis platform, named Willem™, to detect Transthyretin cardiac amyloidosis (ATTR-CA). Thus, this study will assess Willem™ ability to distinguish between truly diagnosed ATTR-CA patients and confirmed non-ATTR-CA patients from ECG data.

Transthyretin cardiac amyloidosis causes debilitating heart failure in older adults. The proposed research will develop a personalized exercise training program to improve functional capacity in patients on optimal treatment for transthyretin cardiac amyloidosis. This is a vital next step to improve functional capacity and quality of life of people suffering from transthyretin cardiac amyloidosis.