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.