Myocardial work assessment to improve baseline risk stratification in patients with transthyretin amyloidosis

Background: Cardiac transthyretin (ATTR) amyloidosis is an often underdiagnosed and potentially fatal disorder associated with poor survival. The National Amyloidosis Centre (NAC) staging system, based on NT-proBNP level and eGFR value, discriminates patients according to survival rates. However, NAC stage II involves a heterogenous group of patients with variable prognosis. This retrospective single-center study was set up to explore the potential role of myocardial work (MW) analysis to enhance risk stratification of ATTR patients prior to therapy. Methods and Results: 37 patients diagnosed with ATTR between March 2021 and August 2023 were included. Baseline NT-proBNP and eGFR values were collected and LVEF, GLS and MW parameters were obtained from stored echocardiographic images. Patients were categorized per NAC stage (16 NAC I, 13 NAC II and 8 NAC III). Whereas the survival rate in NAC II and NAC III was significantly worse than in NAC I (p = 0.031 and p = 0.045 respectively), no significant difference was found between NAC II and III. In the ROC analysis, GCW proved to be the best survival predictor (AUC: 0.7) with optimal cut-off value 1294 mmHg%. Patients from NAC stage II were re-stratified according to GCW cut-off into HIGH RISK together with patients from NAC III or LOW RISK together with patients from NAC I. Patients in the HIGH RISK group exhibited a significantly worse prognosis with only 40 % survival at 2 years follow-up. Conclusion: Our results demonstrate the advantages of incorporating MW analysis, particularly the use of a GCW cut-off, in the baseline risk stratification of ATTR patients.