Associazione Nazionale Medici Cardiologi Ospedalieri

CONGRESS ABSTRACT

CONGRESS ABSTRACT

AL-Amyloidosis related Advanced Heart Failure diagnosed through F-18-Flutemetanol PET scan

Calabrese Alice Bergamo(BG) РASST Papa Giovanni XXIII Bergamo | Ghisletti Andrea Novara(NO) РUniversità del Piemonte Orientale | Gori Mauro Bergamo(BG) РASST Papa Giovanni III Bergamo

BACKGROUND

Systemic amyloidosis (SA) is a group of rare diseases in which abnormal misfolded proteins, amyloid fibrils, accumulate in tissue. The gold standard for diagnosis is tissue biopsy of the affected organ, but it is invasive and needs specific proteomic or immunohistochemistry analyses to characterize the involved protein. We report a case of a complex diagnosis of SA in an advanced heart failure (HF) patient.

METHODS AND RESULTS

A 68-year-old woman with history of recurrent uveitis started to complain dyspnea in 2022, after Covid19. Since her symptoms worsened, in June 2023 she was diagnosed in another center with restrictive cardiomyopathy with preserved left ventricular (LV) ejection fraction. She underwent coronary angiography (unremarkable), cardiac MRI (aspecific fibrosis), and a FDG-PET scan which showed non-homogeneous LV fixation. The patient was treated with steroids for the suspicion of an immunologic-inflammatory disease, without benefit.

Fourteen months after the initial presentation, she was admitted to our centre for advanced inotrope-dependent HF. She had mildly increased LV hypertrophy and severe systolic dysfunction with restrictive physiology and, notably, peri-orbital subcutaneous hemorrhages (Figure 1). Hematological screening for amyloidosis showed elevated serum free lambda light chains. Repeated cardiac MRI scan was consistent with infiltrative disease. A total-body PET scan with dual tracer was performed. The control session with F-18-FDG showed mild aspecific cardiac uptake in the basal septum and lateral wall (Figure 2), while off-label use of F-18-Flutemetanol, an Alzheimer ‘s disease approved experimental tracer that binds to amyloid fibrils beta sheets with very high sensitivity and specificity, showed intense cardiac, hepatic, pulmonary and muscular uptake, with wash-out-timing diagnostic for AL-SA (Figure 3). Periumbilical fat biopsy confirmed the clinical suspicion of SA. Hematological investigations led to the diagnosis of stage I-A lambda micromolecular multiple myeloma, with systemic amyloidosis and a IIIb cardiac prognostic score.

CONCLUSIONS

Endomyocardial biopsy is an invasive procedure and periumbilical fat biopsy discriminates the amyloid protein type only by proteomic analysis, which is available in very few Italian centres. The off-label use of Alzheimers’ PET tracers could reduce the delay of cardiac AL-SA diagnosis, allowing early disease identification and prompting timely hematological therapy.