Challenges and Strategies in the Diagnosis of Cardiac Amyloidosis.

The diagnosis of cardiac amyloidosis can be challenging because it is regarded as a rare disease, frequently presents with nonspecific signs and symptoms, and there are a variety of diagnostic tests available. Approaches for the evaluation of patients with suspected cardiac amyloidosis have improved dramatically in recent years. The initial workup is similar to all patients with heart failure, and certain findings on routine investigations may heighten the index of suspicion. Laboratory testing to screen for light chain (AL) amyloidosis must be performed in all patients, prompting further hematologic assessment if abnormalities are identified. Nuclear scintigraphy with bone-seeking radiotracer has emerged as an effective technique for diagnosing cardiac transthyretin amyloidosis (ATTR) noninvasively. Patients with ATTR cardiac amyloidosis should be referred for genetic testing to confirm or exclude a transthyretin gene mutation. Endomyocardial biopsy remains the diagnostic gold standard and should be performed if the evaluation yields equivocal or discordant findings; however, this is becoming necessary less often, owing to the improved diagnostic yield of noninvasive cardiac imaging modalities. As a result, patients may be diagnosed at earlier stages of disease, potentially improving their likelihood of response to therapy and overall prognosis.