AimsLight chain amyloidosis (AL) patients with heart failure (HF) are usually with revised Mayo (rMayo) stage III/IV disease and have a poor prognosis. We sought to investigate whether and what echocardiographic phenotype provides value for further risk stratification and guiding optimal risk-adapted treatment in this subgroup of AL patients.Methods and Results95 AL patients who presented with HF and were on rMayo stage III/IV were retrospectively included. Of them, 51 patients (53.7%) were with stage III, 44 (46.3%) were with stage IV, and 44 (46.3%) underwent chemotherapy. Laboratory and echocardiographic measurements were acquired before the initiation of chemotherapy. The relevance of different variables with survival was assessed in the entire cohort, chemotherapy, and non-chemotherapy group. By Multivariate Cox regression analysis, right ventricular wall thickness (RVT) [HR 1.145, 95% confidence interval (CI) 1.026-1.279, P = 0.016], relative wall thickness (RWT) (HR 6.709, 95% CI 1.101-40.877, P = 0.039), and left ventricular ejection fraction (LVEF) < 50% (HR 1.939, 95% CI 1.048-3.590, P = 0.035) were found to be independently associated with survival in the entire cohort, RWT (HR 15.488, 95% CI 2.045-117.292, P = 0.008) in the non-chemotherapy group, and RVT (HR 1.331, 95% CI 1.054-1.681, P = 0.016) in the chemotherapy group, respectively. Kaplan-Meier survival analysis revealed that survival was significantly reduced in the presence of RVT >= 6.5 mm or LVEF < 50% in the entire cohort, and the significance of RVT >= 6.5 mm was irrespective of rMayo stages. In the chemotherapy group, survival was decreased if RVT >= 6.5 mm alone or together with RWT >= 0.67 were present, particularly in patients on rMayo stage IV.ConclusionsEchocardiographic phenotype provides incremental value beyond rMayo staging for predicting survival and could further guide treatment in advanced AL with HF. Those with high-risk echocardiographic phenotypes as higher RVT and RWT and lower LVEF had a worse prognosis.