Clinical Research Directory

Inclusion Criteria: * Diagnosis of transthyretin cardiac amyloidosis confirmed by all protocol-specified diagnostic criteria or by Congo red-positive tissue biopsy with cardiac involvement. The diagnostic criteria listed in the current protocol include: * Interventricular septal thickness \>12 mm on echocardiography or cardiac magnetic resonance imaging, in the absence of other causes of hypertrophy (e.g., hypertension or aortic stenosis) * History of signs or symptoms of heart failure consistent with cardiac amyloidosis * Cardiac scintigraphy with technetium-99m pyrophosphate showing grade II or III uptake according to the Perugini scale * Age \>18 years * New York Heart Association (NYHA) functional class II, III, or IV Exclusion Criteria: * Previous adverse reaction, intolerance, or other contraindication to trimetazidine * Serum kappa/lambda ratio outside the normal range * Use of calcium channel blockers, beta-blockers, or nitrates * Obstructive coronary artery disease, defined as \>50% stenosis in any major epicardial coronary artery, demonstrated by coronary computed tomography angiography * Active infection, inflammatory disease, or other systemic condition that may affect myocardial perfusion * Contraindication to dipyridamole or PET/CT imaging * Estimated glomerular filtration rate \<30 mL/min/1.73 m², calculated using the CKD-EPI equation * Pregnancy or postpartum period * Presence of diseases other than cardiac amyloidosis that may impair functional capacity or limit ambulation during the 6-minute walk test * Other medical conditions or comorbidities that, in the investigator's opinion, may interfere with the course of the study or interpretation of the data * Refusal to provide written informed consent