Abstract 14407: Regression of Cardiac AL Amyloid by Cardiovascular Magnetic Resonance
Introduction: Cardiac involvement in immunoglobulin light chain (AL) amyloidosis is the major determinant of survival; Cardiac response to chemotherapy is conventionally assessed by serum brain natriuretic peptide (NT-proBNP) and echocardiography, but neither quantify amyloid burden and the latter seldom suggests improvement.
Hypothesis: The aim of this study was to evaluate cardiac AL amyloid serially using cardiovascular MR (CMR) including extracellular volume measurement (ECV), which is the site of the amyloid deposits.
Methods: 28 patients with cardiac AL amyloidosis who had chemotherapy were studied serially using ECG, echocardiography, 123I-labeled serum amyloid P component (SAP) scintigraphy, NT-proBNP measurements and CMR with T1 mapping and ECV measurements.
Results: Eighteen patients achieved a complete or very good partial haematological response (CR n=10; VGPR n=8). Ten patients attained a partial response (PR) or no response (NR). At follow-up (mean 18±12months), the amyloid burden had decreased substantially among patients attaining a CR or VGPR (ECV 56±11% falling to 43±10%; estimated amyloid burden 91±34ml falling to 72±35ml p=0.03). There was significant reduction in NT-proBNP concentration, LV mass, left atrial area and improvement in diastolic function in patients whose amyloid burden decreased. Regression of cardiac amyloid by CMR correlated with regression of amyloid in other organs measured by SAP scintigraphy. Concordance between regression of cardiac amyloid and reduction in NT-proBNP was 66%.
Conclusions: In contrast to traditional echocardiography, CMR with T1 mapping and ECV measurements demonstrates that cardiac AL amyloid deposits frequently regress following chemotherapy that substantially suppresses clonal light chain production.
Author Disclosures: A. Martinez-Naharro: None. A. Abdel-Gadir: None. T.A. Treibel: None. G. Zumbo: None. D.S. Knight: None. S. Rosmini: None. T. Lane: None. S. Mahmood: None. S. Sachchithanantham: None. C.J. Whelan: None. H.J. Lachmann: None. A.D. Wechalekar: None. P. Kellman: None. J.D. Gillmore: None. J.C. Moon: Research Grant; Modest; GSK research grant. Consultant/Advisory Board; Modest; Consultancy fee for trial design. P.N. Hawkins: None. M. Fontana: None.
- © 2016 by American Heart Association, Inc.