Quantification of right ventricular amyloid burden with 18F-florbetapir positron emission tomography/computed tomography and its association with right ventricular dysfunction and outcomes in light-chain amyloidosis

• Published in: European heart journal cardiovascular imaging 2024-04, Vol.25 (5), p.687-697
• Main Authors: Datar, Yesh, Clerc, Olivier F, Cuddy, Sarah A M, Kim, Sirwoo, Taylor, Alexandra, Neri, Jocelyn Canseco, Benz, Dominik C, Bianchi, Giada, Yee, Andrew J, Sanchorawala, Vaishali, Ruberg, Frederick L, Landau, Heather, Liao, Ronglih, Kijewski, Marie Foley, Jerosch-Herold, Michael, Kwong, Raymond Y, Di Carli, Marcelo F, Falk, Rodney H, Dorbala, Sharmila
• Format: Article
• Language: English
• Subjects: Aged; Aniline Compounds; Ethylene Glycols; Female; Heart Ventricles - diagnostic imaging; Humans; Immunoglobulin Light-chain Amyloidosis - complications; Immunoglobulin Light-chain Amyloidosis - diagnostic imaging; Male; Middle Aged; Positron Emission Tomography Computed Tomography - methods; Prospective Studies; Radiopharmaceuticals; Ventricular Dysfunction, Right - diagnostic imaging
• ISSN: 2047-2404; 2047-2412; 2047-2412
• DOI: 10.1093/ehjci/jead350

In systemic light-chain (AL) amyloidosis, quantification of right ventricular (RV) amyloid burden has been limited and the pathogenesis of RV dysfunction is poorly understood. Using 18F-florbetapir positron emission tomography/computed tomography (PET/CT), we aimed to quantify RV amyloid; correlate RV amyloid with RV structure and function; determine the independent contributions of RV, left ventricular (LV), and lung amyloid to RV function; and associate RV amyloid with major adverse cardiac events (MACE: death, heart failure hospitalization, cardiac transplantation). We prospectively enrolled 106 participants with AL amyloidosis (median age 62 years, 55% males) who underwent 18F-florbetapir PET/CT, magnetic resonance imaging, and echocardiography. 18F-florbetapir PET/CT identified RV amyloid in 63% of those with and 40% of those without cardiac involvement by conventional criteria. RV amyloid burden correlated with RV ejection fraction (EF), RV free wall longitudinal strain (FWLS), RV wall thickness, RV mass index, N-terminal pro-brain natriuretic peptide, troponin T, LV amyloid, and lung amyloid (each P < 0.001). In multivariable analysis, RV amyloid burden, but not LV or lung amyloid burden, predicted RV dysfunction (EF P = 0.014; FWLS P < 0.001). During a median follow-up of 28 months, RV amyloid burden predicted MACE (P < 0.001). This study shows for the first time that 18F-florbetapir PET/CT identifies early RV amyloid in systemic AL amyloidosis prior to alterations in RV structure and function. Increasing RV amyloid on 18F-florbetapir PET/CT is associated with worse RV structure and function, predicts RV dysfunction, and predicts MACE. These results imply a central role for RV amyloid in the pathogenesis of RV dysfunction.