Background: Echocardiographic-determined left ventricular mass index (LVMI) provides quantitative information on left-ventricular structure. However, its prognostic value on light-chain (AL) amyloidosis has not been clearly defined.
Methods: We included 99 patients with newly diagnosed AL amyloidosis between July 2013 and March 2022. Clinical features and echocardiographic parameters were collected.
Results: LVMI ≥113.4 g/m2 was predictive for overall survival (OS) and progression-free survival (PFS) with respective hazard ratios (HRs) of 2.87 (95% CI: 1.04-7.79) and 2.91 (95% CI: 1.25-6.68). Patients in the LVMI-high group had higher NT-proBNP, cTnT, and FLC-diff levels. They were more likely to be cardiac involved and have increased mean left ventricular wall thickness, decreased left ventricular ejection fraction, and higher proportion of patients with pericardial effusion. In subgroup analysis, LVMI-high group was associated with a reduced OS [HR: 4.74 (95% CI: 1.26-17.77)] and PFS [HR: 7.16 (95% CI: 2.10-24.40)] in patients with cardiac amyloidosis (CA). Besides, LVMI-high was associated with a reduced OS [HR: 3.58 (95% CI: 1.17-11.02)] and PFS [HR: 4.79 (95% CI: 1.77-12.94), p = 0.00] among patients staged of II or III (Mayo 2004), as well as reduced OS [HR: 22.65 (95% CI: 1.66-299.31)] and PFS [HR: 18.73 (95% CI: 2.36-148.35)] among patients staged of III or IV (Mayo 2012).
Conclusions: LVMI is a reliable prognostic indicator of survival. A cut-off of LVMI (113.4 g/m2) was prognostic for OS and PFS. Importantly, LVMI was able to identify a subset of patients with poorer prognosis in the context of CA or in the late stages according to the biomarker staging systems.
Keywords: Amyloidosis; LVMI; echocardiography; left ventricular mass index; prognosis.