Purpose: Cardiac amyloidosis (CA) is a morphological and functional disorder caused by the deposition of amyloid fibers in the myocardial interstitium. Effective treatments for CA have been established in recent years, making an early diagnosis more important. The aim of this study was to clarify the clinical background, physical, and electrocardiogram (ECG) findings that should be confirmed for the diagnosis in addition to the echocardiographic findings of CA.

Subjects and Methods: The subjects were 48 patients (37 men, age 69 ± 13 years) who had undergone a close examination for CA at our hospital. Patients were classified into two groups: a CA-confirmed group (25 patients) and a CA-negative group (23 patients). We compared the age, gender, medical history, CA-related diseases, electrocardiographic indices, and echocardiographic indices between the two groups. In addition, we created an algorithm to systematically evaluate the potential for CA.

Results and Discussion: We observed significant differences in age, presence of hemodialysis, CA-related diseases, ECG potential, ventricular septal wall thickness, left ventricular posterior wall thickness, mean wall thickness, presence of atrial septal or right ventricular wall thickening, left ventricular end-diastolic diameter, mean longitudinal strain (LS) at the base, and mean LS at the apical area/basal LS. We observed a false infarction pattern on the electrocardiogram only in the definite group, although the difference was not statistically significant. We created an algorithm to identify the possibility of CA from the obtained data. The 48 cases were classified as low, medium, and high probability of CA. All 15 cases classified as high probability had confirmed CA, whereas all 11 cases classified as low were in the negative group.

Conclusion: During the echocardiographic examination, the presence or absence of electrocardiographic findings and related diseases in addition to echocardiographic findings during echocardiography can lead to the diagnosis of CA.