Prognostic mortality factors in advanced light chain cardiac amyloidosis: A prospective cohort study.

Abstract

Predicting mortality in severe AL cardiac amyloidosis is challenging due to elevated biomarker levels and limited thresholds for stratifying severe cardiac damage. This prospective, observational, cohort study included de novo, confirmed cardiac AL amyloidosis patients at the Henri Mondor National Reference Centre. The goal was to identify predictors of mortality to enhance prognostic stratification and improve informed decision-making regarding therapy. Over the 12-year study period, among the 233 patients included, 133 were NYHA III-IV and 179 Mayo 2004 III. The independent predictors for mortality identified were hsTnT, NT-proBNP, cardiac output, and conjugated bilirubin. A novel prognostic, conditional stratification, Mondor amyloidosis cardiac staging (MACS) was developed with biomarker cut-off values for Stage 1: hsTnT≤107ng/L and NT-proBNP≤3867ng/L (n=77; 33%); for stage 2 NT-proBNP>3867ng/L (n=72; 30%). For stage 3, if troponin >107ng/L, regardless of NT-proBNP then CB 4μmol/L, was added (n=41; 17.5%) and stage 4: CB>4μmol/L (n=43; 18.5%). The median overall survival was 8months 95% CI [2-24]. At 1year, 102 (44%) patients died and the Kaplan-Meier median survival with MACS Stage 1 was not reached, while stage 2 was 15.2months (95% CI [11-18]) and stage 3, 6.6months (95% CI [1-13]). Notably, among European stage II patients, 17.1%, n=8 were MACS stage 3 and European stage IIIb 21.4% (n=23) were MACS stage 4. Importantly, among European stage IIIb patients 42.2% (n=29) were classified MACS stage 4 and 12.5% n=9 were only MACS stage 2. The Mondor prognostic staging system, including conjugate bilirubin may significantly improve prognostic stratification for patients with severe cardiac amyloidosis.