An 81 year old man presents with progressive exertional dyspnea and lower extremity edema. Echocardiography shows concentric ventricular thickening with preserved ejection fraction, and ECG shows low voltage. Serum immunofixation is negative for monoclonal protein. Which of the following proteins most likely accounts for the extracellular deposits causing this condition?
- A)Collagen type III
- B)Wild type or mutant transthyretinGABARITO
- C)Immunoglobulin lambda light chain
- D)Apolipoprotein B
- E)Beta amyloid precursor protein
Explicação
Wild type transthyretin can deposit in older adults and cause senile cardiac amyloidosis with restrictive physiology. The discordance between increased wall thickness on echocardiogram and low voltage on ECG is a classic clue to cardiac amyloid. Ver explicação completa e trilha adaptativa →