Cardiac Magnetic Resonance and Echocardiography Study With Acoramidis

Key Inclusion Criteria: * Participants aged 18 to 80 * Confirmed diagnosis of ATTR-CM requiring targeted therapy * At screening: New York Heart Association (NYHA) Class I/II; estimated glomerular filtration rate (eGFR) ≥40 mL/min/1.73m2; left ventricular ejection fraction (LVEF) \>35%; left ventricular (LV) wall thickness ≥12 mm. * Heart failure condition has been clinically stable for at least 6 weeks prior to screening. Key Exclusion Criteria: * Current or planned implantation of a cardiac implantable electronic device (eg, pacemaker, implantable cardiac defibrillator). * Acute myocardial infarction, acute coronary syndrome or coronary revascularization, or experienced stroke or transient ischemic attack within 90 days prior to screening. * Hemodynamic instability. * Likely to undergo heart transplantation within 12 months from screening. * Confirmed diagnosis of AL amyloidosis at screening. * At screening: NYHA Class III/IV; National Amyloidosis Center (NAC) Stage 3. * Prior or current treatment with acoramidis.