What about markers inflammation on cardiac amyloidosis?

Abstract

Introduction

Prognosis in cardiac amyloidosis has always been associated with amyloid infiltration, but there is increasing evidence of the role of inflammation and systemic immune response caused by the toxicity of free light chains and amyloid fibrils. However, there is very little knowledge about the systemic inflammation markers, their differential value, and prognostic significance in amyloidosis subtypes.

Objective

Differential value of inflammation markers and prognostic significance in amyloidosis subtypes.

Method

Prognostic markers well-known in AA amyloidosis, such as IL-6, calprotectin, and amyloide serique A (SAA), were measured at diagnosis and compared among AL, ATTR amyloidoses, and other cardiopathies.

Results

Pilot study of 147 patients (25 AL, 80 ATTR, and 42 others) with respective median ages of 76 years, 83 years, and 70 years, the median left ventricular function was 51.5% (±5), 52% (±4), and 48% (±6), with a median follow-up of 563 [20–590] days. Results showed a high incidence of inflammation with dissociation of markers in AL and ATTR-CA, For AL, the markers were higher,for ATTR-CA, there was some inflammatory substrate, less marked than in AL but more significant than in other cardiopathies. A certain population of ATTR-CA had a higher inflammatory profile (calprotectin and SAA). For other cardiopathies, the profile was rather homogeneous: the IL-6 was at 25.4 ± 37 pg/ml, the Calprotectin at 10.3 ± 21 mg/L, and the SAA at 14.8 ± 37 mg/L compared to 8.5 ± 9.9 pg/ml, 3.3 ± 5.6 mg/L, and 10.5 ± 9.2 mg/L, respectively, for ATTR and others cardopathies. Patients with elevated IL-6 levels were the most severe (higher Troponin, NT-proBNP, and lower LVEF). Calprotectin was well correlated with NT-proBNP and LVEF (R = 0.76 and 0.77, P = 0.04 and 0.001, respectively). IL-6 was the only marker with iprognostic value with a Hazard ratio of mortality at 2 years at 1.67 [1.11–12.45] in AL and ATTR amyloidoses (independent of troponin, LVEF, and NT-proBNP), and a value above 22 pg/ml increased mortality at 2 years by 20% in ATTR and early mortality by 33% in AL (3 months).

Conclusion

Inflammation is part of the pathophysiology of amyloidosis and increases morbidity and mortality, especially in AL amyloidosis. Treating amyloidosis would likely involve addressing this aspect in addition to others.