Abstract
RATIONALE: Amyloid cardiomyopathy (AC) is a rare and fatal condition, often with a delayed diagnosis due to its nonspecific initial presentations. This case underscores the diagnostic challenge and critical importance of early recognition when patients present with seemingly unrelated gastrointestinal symptoms. PATIENT CONCERNS: A 48-year-old woman initially presented with abdominal pain, back pain, and constipation, which were managed as gastrointestinal disorders. Her condition progressed rapidly to include severe cardiac symptoms, including chest tightness and dyspnea. DIAGNOSES: Cardiac magnetic resonance imaging revealed findings indicative of AC, including left ventricular hypertrophy, diffuse delayed enhancement, and atrial enlargement. The diagnosis of immunoglobulin light chain amyloidosis was confirmed by endomyocardial biopsy, which was positive for κ light chains. INTERVENTIONS: Supportive care for heart failure, including diuretics and beta-blockers, was initiated. However, specific therapies targeting the underlying immunoglobulin light chain amyloidosis could not be administered due to the patient's rapid clinical deterioration. OUTCOMES: The patient died 2 days after the pathological diagnosis was established, highlighting the aggressively progressive nature of the disease. LESSONS: This case highlights that AC can manifest with prominent gastrointestinal symptoms before overt cardiac involvement. It is crucial to consider systemic amyloidosis in the differential diagnosis for patients with multisystem involvement, as early, multidisciplinary evaluation is essential for potentially improving outcomes in this fatal condition.