A novel echocardiographic risk score for light-chain amyloidosis

Abstract

Abstract Aims The prognosis of light-chain (AL) amyloidosis, a plasma cell dyscrasia, is largely determined by the presence of cardiac involvement. Conventional staging is achieved using cardiac biomarkers (high-sensitivity troponin, N-terminal pro-beta natriuretic peptide) and free light-chain difference (Mayo staging). We sought to evaluate the role of echocardiographic parameters as prognostic markers in AL amyloidosis and examine their utility compared with conventional staging. Methods and results Seventy-five consecutive patients with AL amyloidosis reviewed at a referral amyloid clinic who underwent comprehensive echocardiographic assessment were retrospectively identified. The evaluated echocardiographic parameters included left ventricular (LV) ejection fraction, mass, diastolic function parameters, global longitudinal strain (GLS), and left atrial (LA) volume. Mortality was assessed through a review of clinical records. During a median follow-up of 51 months, 29/75 (39%) patients died. Patients who died had a larger LA volume (47 ± 12 vs. 35 ± 10 mL/m2, P < 0.001) and a higher E/e′ (18 ± 10 vs. 14 ± 6, P = 0.026). Univariate clinical and echocardiographic predictors of survival included LA volume, E/e′, e′, LVGLS, and Mayo stage (at significance of P < 0.1). Left atrial volume and LVGLS were significant determinants of mortality when examined using clinical cut-offs, although E/e′ was not. A composite echocardiographic risk score comprising LA volume and LVGLS provided similar prognostic performance to Mayo stage [area under the curve (AUC) 0.75, 95% confidence interval (CI) 0.64–0.85 vs. AUC 0.75, 95% CI 0.65–0.858, P = 0.91]. Conclusion Left atrial volume and LVGLS were independent predictors of mortality in AL amyloidosis. A composite echocardiographic score combining LA volume and LVGLS has similar prognostic power to Mayo stage for all-cause mortality.