Right ventricular global longitudinal strain by cardiac magnetic resonance provides incremental prognostic value in light-chain amyloidosis
A Briasoulis, V Mikros, N Lama, F Theodorakakou, R Patras, N Kelekis, M A Dimopoulos, K Stamatelopoulos, E KastritisAbstract
Background
Right ventricular (RV) involvement is increasingly recognised as a major determinant of prognosis in light-chain (AL) amyloidosis, yet robust and modality-specific imaging markers for RV risk stratification remain limited.
Purpose
To assess the prognostic value of cardiac magnetic resonance (CMR)–derived right ventricular global longitudinal strain (RVGLS) and its incremental contribution beyond established clinical staging and biomarkers in AL amyloidosis.
Methods
In a prospective cohort of patients with AL amyloidosis undergoing CMR, clinical, laboratory, echocardiographic, and CMR parameters were collected at baseline. All-cause mortality was the primary endpoint. Group comparisons were performed using the independent-samples t-test or Mann–Whitney U test. A two-sided p value < 0.05 was considered statistically significant. Time-to-event analyses were performed using Cox proportional hazards models with follow-up administratively censored at 72 months. Discriminatory performance was assessed using receiver operating characteristic (ROC) analysis and Kaplan–Meier survival analysis.
Results
Among 100 patients (25 deaths), non-survivors exhibited higher circulating free light chain levels and NT-proBNP concentrations (all p<0.05). Conventional left and right ventricular volumes, ejection fraction, and myocardial tissue-characterisation parameters did not differ significantly between groups (Table 1). In contrast, CMR-derived RVGLS was significantly impaired in non-survivors compared with survivors (−16.05% vs −19.82%, p<0.001) and emerged as the strongest imaging predictor of mortality in univariable analysis (hazard ratio 1.17 per 1% worsening, p<0.001). RVGLS demonstrated good discriminatory performance for mortality (AUC 0.74, 95% CI 0.63–0.85; Figure 1A), with an optimal cut-off at −16.4%. Patients with RVGLS ≥ −16.4% showed significantly reduced survival (log-rank p<0.001; Figure 1B). Echocardiographic RVGLS showed limited agreement with CMR-derived RVGLS and lower overall discriminatory performance.
Conclusions
CMR-derived RVGLS is a robust and independent predictor of mortality in AL amyloidosis and provides incremental prognostic value beyond established clinical staging and biomarkers. RVGLS enables clinically meaningful risk stratification and identifies a high-risk subgroup with markedly reduced survival.Figure 1.For image description, please refer to the figure legend and surrounding text.Table 1.For image description, please refer to the figure legend and surrounding text.