Right ventricular free wall strain predicts transthyretin amyloidosis prognosis as well as biomarker-based staging systems.

AIMS

The diagnosis of transthyretin amyloidosis (ATTR) significantly impacts the management and prognosis of patients initially presenting with heart failure (HF). Despite recent advancements in treatment, prognosticating ATTR remains challenging. In this study, we aim to assess echocardiographic parameters associated with mid-term prognosis in patients with wild-type ATTR using a biomarker staging system as a reference point.

METHODS AND RESULTS

We studied 182 consecutive patients with wild-type ATTR (91% male and median age 82 years) who were referred to our centre between 2016 and 2022. Using N-terminal pro-B-type natriuretic peptide and estimated glomerular filtration rate cut-offs, we classified patients into the following three stages: Stage I (101 patients, 55.5%), Stage II (53 patients, 29.0%), and Stage III disease (28 patients, 15.5%). We then compared traditional echocardiographic indices and markers of subclinical ventricular dysfunction [left ventricular (LV) global longitudinal strain, right ventricular (RV) free wall strain, and left atrial (LA) strain] among groups. Over a fixed follow-up period of 18 months, which included treatment with tafamidis 61 mg daily, 48 patients (26.4%) experienced the composite outcome of death or HF hospitalization. When compared with Stage I ATTR, the hazard ratio (HR) for death or hospitalization was 1.55 [95% confidence interval (CI) 0.62-3.86] for Stage II ATTR and 4.53 (95% CI 1.66-12.4, P = 0.0116) for Stage III ATTR. Among echocardiographic parameters, reduced RV free wall strrain (FWS) was independently associated with all-cause mortality or HF hospitalization after adjustment for the staging system (HR 2.03, 95% CI 1.07-3.85, P < 0.05).

CONCLUSION

RV FWS should be routinely assessed for all patients with ATTR. It is an independent predictor of poor prognosis and provides additional value beyond biomarker staging systems.