Open AccessStep‐by‐step typing for the accurate diagnosis of concurrent light chain and transthyretin cardiac amyloidosis
Author(s) -
Moriyama Hidenori,
Kitakata Hiroki,
Endo Jin,
Ikura Hidehiko,
Sano Motoaki,
Tasaki Masayoshi,
Sakai Shunta,
Ueda Mitsuharu,
Fukuda Keiichi
Publication year - 2022
Publication title -
esc heart failure
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.787
H-Index - 25
ISSN - 2055-5822
DOI - 10.1002/ehf2.13773
Subject(s) - cardiac amyloidosis , transthyretin , amyloidosis , medicine , cardiomyopathy , heart failure , al amyloidosis , amyloid (mycology) , restrictive cardiomyopathy , laser capture microdissection , scintigraphy , pathology , immunoglobulin light chain , antibody , chemistry , gene expression , biochemistry , gene , immunology
While 99m Tc‐pyrophosphate scintigraphy is clearly useful in diagnosing transthyretin amyloid cardiomyopathy (ATTR‐CM), it is necessary to know the pitfalls of this test for proper use. We present a rare case of concurrent ATTR‐CM and amyloid light chain (AL) cardiomyopathy. The patient showed congestive heart failure with left ventricular hypertrophy. 99m Tc‐pyrophosphate scintigraphy revealed abnormal cardiac uptake of Grade 3, a typical feature for ATTR‐CM. However, the patient showed renal impairment with proteinuria and the presence of monoclonal gammopathy, which rather suggested AL amyloidosis. Endomyocardial biopsy, immunohistochemistry, and proteomic analysis by laser microdissection with liquid chromatography‐coupled tandem mass spectrometry were performed, which finally confirmed both ATTR‐CM and AL cardiomyopathy. This case implicates the importance of combining examinations and precisely interpreting the results to diagnose cardiac amyloidosis accurately.