[The prognostic value of baseline serum free light chain in immunoglobulin light-chain cardiac amyloidosis].

To analyze the prognostic value of baseline serum free light chain (sFLC) in immunoglobulin light-chain cardiac amyloidosis (AL-CA) . Thirty patients diagnosed with AL-CA from January 2012 to December 2016 at Beijing Chaoyang Hospital were included in this study to retrospectively evaluate the clinical data. The cut-off value of dFLC (involved sFLC minus uninvolved sFLC) was determined according to the receiver operator characteristic curve (ROC) and grouped, the prognoses of both groups were evaluated. The onset age of all AL-CA patients was 57 years old. It occurred more commonly in men (21 cases, 70%) and the light chains of immunoglobulin composed mainly of type λ (22 cases, 73.3%) . Renal involvements occurred in 17 cases (56.7%) . The median value of difference between involved and uninvolved serum immunoglobulin free light chain levels (dFLC) was 162.9 (57.9-401.6) mg/L. More subjects in the high dFLC group had higher BNP (=0.005) , and shorter median survival than those in the low dFLC group (15 months 47 months, <0.001) . Similar results of median survival were observed when the patients were redivided by a new cut-off value of 180 mg/L for dFLC (high dFLC group: 22 months, low dFLC group: 40 months, =0.001) , or a κ/λ ratio in which patients with κ type sFLC-ratio<3.79 and λ type sFLC-ratio≥0.06 were grouped into the low sFLC-ratio (37 months) , and the reverse the high sFLC-ratio ones (25 months, =0.021) . In multivariate analysis, dFLC and New York Heart Association (NYHA) classification of cardiac function were two risk factors associated with all-cause mortality in patients, of them the hazard ratio for higher dFLC was 12.13 (95% 2.98-49.30, <0.001) . Measurement of the sFLC level could implicate the prognosis of AL-CA.