BACKGROUND Amyloidosis is a group of diseases characterized by the pathological deposition of misfolded proteins in various organs, including the heart, leading to structural and functional alterations. The primary types of cardiac amyloidosis are light chain amyloidosis and transthyretin amyloidosis. Early diagnosis is critical for effective management. This report describes the case of a 68-year-old Colombian man presenting with heart failure and a diagnosis of cardiac amyloidosis. CASE REPORT A 68-year-old man presented with heart failure symptoms, biceps tendon rupture, neuropathic pain in the extremities, and an electrocardiogram showing low QRS voltage and a pseudo-infarct pattern. Transthoracic echocardiogram revealed a left ventricular ejection fraction of 30%, severely thickened walls with a speckled appearance, a global longitudinal strain of -6.2% in a bull's eye pattern, and a left ventricular posterior wall thickness of 21.3 mm. Cardiac magnetic resonance imaging showed severe symmetric hypertrophy, moderate global dysfunction, and an elevated native T1 value of 1225 milliseconds. Post-gadolinium T1 mapping revealed a significantly increased extracellular volume of 72%. Perugini grade 3 pyrophosphate scintigraphy, negative hematological tests, and endomyocardial biopsy confirmed the diagnosis of amyloidosis, without monoclonal spikes. Genetic testing identified a heterozygous c.424G>A (p.Val142Ile) variant in the transthyretin gene, consistent with variant transthyretin amyloidosis. CONCLUSIONS Amyloidosis may affect up to 13% of patients with heart failure and preserved ejection fraction. Early recognition of red flags and implementation of a diagnostic algorithm are crucial for timely intervention in this population.