The Role of Echocardiogram and Cardiac Rhythm Analysis for Early Detection of Cardiac Amyloidosis.

Purpose: The purpose of this integrative review was to establish the role of cardiac rhythm analysis (electrocardiogram; EKG) and echocardiogram in increasing clinical suspicion for and earlier diagnosis of cardiac amyloidosis. Methods: A literature review was conducted using PubMed and Scopus databases. Dates searched were from January 2017 to May 2021. Inclusion criteria included a diagnosis of cardiac amyloidosis, use of EKG, and echocardiogram participants 18 years and older. Articles were excluded if they were duplicates, had an irrelevant title, or were incomplete. Results: Results indicated neither EKG nor echocardiogram alone or in combination are sufficient for diagnosing cardiac amyloidosis. There is, however, a combination of findings that could potentially prove useful in "ruling in" cardiac amyloidosis and prompt further evaluation. Predominant findings in cardiac amyloidosis cohorts found on EKG showed low-voltage QRS complexes, a pseudo-infarct pattern in precordial leads, and an absence of left ventricular hypertrophy on EKG. There is no single echocardiogram finding specific to cardiac amyloidosis. Patients will generally present with thickened ventricular walls, and nearly all patients will display a preserved left ventricular ejection fraction until later stages of disease. Strain imaging, either via 2D or 3D transthoracic echocardiogram, is more useful in screening for or detecting cardiac amyloidosis and should be utilized in this instance. Findings in cardiac amyloidosis include decreased global longitudinal strain and relative apical sparing. Conclusion: Overall, EKG and echocardiogram are effective, feasible, and practical tools to increase clinical suspicion for cardiac amyloidosis for the purposes of early recognition and evaluation. These are useful only to "rule in" a diagnosis. Future studies are needed to validate these findings.