Case report: recurrent chest pain as initial manifestation of rapidly progressing light-chain cardiac amyloidosis with microvascular infiltration-a novel red flag associated with poor outcomes

Background: Angina due to microvascular amyloid infiltration is an under-recognized early red flag of infiltrative disease and should be investigated as a predictor of poor outcomes. Case summary: A 73-year-old man with cardiovascular risk factors and a history of treated obstructive coronary artery disease presented 10 months later with recurrent angina. His condition progressively worsened, with the development of severe dyspnoea. Within 6 months, he succumbed to cardiogenic shock in the presence of severe biventricular dysfunction and unobstructed coronary arteries. Post-mortem diagnosis revealed AL cardiac amyloidosis with massive myocardial infiltration and extensive microvascular amyloid deposits. Discussion: This case underscores chest pain as a critical clinical marker, potentially indicating microvascular amyloid infiltration in patients with light-chain cardiac amyloidosis, particularly those with unobstructed coronary arteries. Its assessment may also have implications for future therapies.