Retinal Fundus Imaging and OCT Imaging for Ocular Detection of ATTR-CM

Inclusion Criteria: * 1\. Participant must be 18 years and older at the time of signing the informed consent form. * 2\. Participants with either of the following: * \- Positive ATTR-CM cases: Participants with a clinical diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM) with amyloid deposits in cardiac or non-cardiac tissue confirmed by Congo Red (or equivalent) staining, or DPD-Tc, PYP-Tc, or HMDP-Tc scintigraphy with Grade 2 or 3 cardiac uptake in the absence of abnormal light chains ratio. * \- Control population: Participants with a clinical diagnosis of guideline-directed medical therapy-directed heart failure (HF) and either: * a) Subgroup A: Definitively excluded ATTR-CM amyloidosis: negative cardiac or non-cardiac tissue biopsy for amyloid, or negative technetium scintigraphy within the past 2 years. * b) Subgroup B: Low probability of ATTR-CM amyloidosis, not definitively excluded: absence of amyloid-suggestive features on echocardiography (ECHO), electrocardiography (ECG), or cardiac magnetic resonance imaging (MRI) within the past 2 years, with documented clinical assessment indicating HF etiology unlikely attributable to amyloidosis; no amyloid-specific testing (technetium scintigraphy or biopsy) performed. * 3\. Participant or legally authorized representative (LAR) must sign the informed consent form. Exclusion Criteria: * 1\. Any known eye condition that may preclude clear imaging of the retina. * 2\. Any known history of amyloid light-chain (AL) amyloidosis. * 3\. Any ocular surgery that, in the opinion of the investigator, makes participation in the study undesirable. * 4\. Any medical condition that, in the opinion of the investigator, makes participation in the study undesirable, for example, if the participant is critically unwell or requires ongoing emergency treatment. * 5\. Involvement in the planning and/or conduct of the study. * 6\. In the opinion of the investigator, the participant is unlikely to comply with study procedures, restrictions, and requirements. * 7\. Previous enrollment in the present study.