Multiple Red Flags of Transthyretin Amyloid Cardiomyopathy in a Single Patient: A Case Report on Diagnostic Challenge

Background: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, infiltrative cardiomyopathy caused by misfolded transthyretin proteins forming amyloid fibers that deposit in the myocardial interstitium. It may present with multi-systems involvement. Diagnostic delay is common due to non-specific symptoms. Case Summary: We present a case of ATTR-CM with autonomic neuropathy as initial symptom, accompanied by multi-system manifestations. After being shuffled between multiple hospitals and departments, it was eventually found that his symptoms matched several "red flags" of ATTR-CM. Following the diagnostic algorithm, he underwent a 99Tcm-PYP imaging and was finally diagnosed with ATTR-CM. In our manuscript, we outline the diagnostic pathway recommended by the latest guidelines and review treatment strategies that are available and emerging. Discussion: Since early diagnosis is crucial for improving clinical outcomes for patients, we would like to highlight the pitfalls in diagnosing this disease and emphasize the need to be aware of its variable clinical presentation and red flags.