Delayed Diagnoses of Cardiac Amyloidosis

Abstract

Cardiac sarcoidosis (CS) can be challenging to accurately diagnose and relies on a complex diagnostic framework because of the limited sensitivity of endomyocardial biopsy. Frequently, the diagnosis of CS depends on cardiac ¹⁸F-fluorodeoxyglucose positron emission tomography, which has limited specificity for sarcoidosis. We report 3 cases of individuals who were initially diagnosed and treated for isolated CS based on multimodality cardiac imaging and later definitively reclassified to wild-type transthyretin cardiac amyloidosis from histopathology obtained by endomyocardial biopsy.

Keywords: cardiac amyloidosis; cardiac sarcoidosis; case report; multimodality imaging; nonischemic cardiomyopathy.

Graphical abstract

Figure 1

Echocardiogram Images for Patient 1 (A) Patient 1 had reduced global longitudinal strain on the echocardiogram. (B) Transthoracic echocardiogram demonstrating mild symmetrical increase in left ventricular wall thickness (1.3 cm) for patient 1.

Figure 2

Cardiac Magnetic Resonance Imaging of Patient 1 Showing Patchy Late Gadolinium Enhancement

Figure 3

Electrocardiogram of Patient 2 Showing First-Degree Atrioventricular Block and a Right Bundle Branch Block

Figure 4

Patient 2 Had Reduced Global Longitudinal Strain on the Echocardiogram With Apical Sparing

Figure 5

Cardiac Magnetic Resonance Imaging of Patient 2 Showing Late Gadolinium Enhancement of the Basal Midinferolateral, Basal Midlateral, and Basal Inferior Wall

Figure 6

Electrocardiogram of Patient 3 Showing Low Voltage in Limb Leads With Pseudoinfarct Pattern

Figure 7

Echocardiogram Images for Patient 3 (A) Patient 3 had reduced global longitudinal strain with apical sparing pattern on transthoracic echocardiogram. (B) Mitral inflow Doppler signal consistent with restrictive filling pattern for patient 3.

Figure 8

Cardiac Magnetic Resonance Imaging for Patient 3 Showing Patchy Late Gadolinium Enhancement

Figure 9

FDG PET Images, Cardiac Magnetic Resonance Images, and Histology for Patients 1 to 3 ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F FDG PET) images, cardiac magnetic resonance (CMR) images, and histology slides for patients 1 to 3 (left to right). ¹⁸F FDG PET images show FDG uptake, CMR images demonstrate delayed gadolinium enhancement, and histology with Congo red stain reveals amyloid deposition.