Incremental Value of Global Longitudinal Strain for Predicting Survival in Patients With Advanced AL Amyloidosis

BACKGROUND: Advanced light-chain (AL) amyloidosis is associated with poor prognosis, with a 5-year survival rate of <25%. Prognostication is based on the revised Mayo (rMayo) staging according to serum cardiac biomarkers. OBJECTIVES: This study sought to determine whether global longitudinal strain (GLS) can provide incremental prognostic value in patients with advanced disease. METHODS: Baseline (pre-treatment) clinical, 2-dimensional echocardiogram with GLS and laboratory data were collected prospectively in 94 patients with newly diagnosed AL amyloidosis with rMayo stage III or IV disease. Overall survival (OS) was defined as time from baseline echocardiography to death. RESULTS: Of 94 patients, 60% (n = 56) had rMayo stage III and 40% (n = 38) had stage IV disease. Ninety of the 94 patients underwent plasma cell-directed therapy. The median left ventricular ejection fraction (LVEF) was 60%, and the median GLS was 13.2%. Of 94 patients, 64 died during follow-up. The median OS was 11.2 months, with an estimated 5-year OS of 21%. In univariable analysis, brain natriuretic peptides, GLS, LVEF, E/e′ ratio, and rMayo stage were significantly associated with OS. In Cox regression, GLS provided incremental value over brain natriuretic peptide, troponin, and LVEF for predicting OS. Patients with GLS < –14.2% had a corresponding median OS and 5-year OS rate of 33.2 months and 39%, respectively, versus 7.7 months and 6% for those with GLS ≥ –14.2%. This difference was maintained despite further stratification by rMayo stage. CONCLUSIONS: Baseline GLS is an independent predictor of OS beyond the circulating biomarkers and can identify groups with different survival outcomes beyond the Mayo Staging.