Development of cardiac amyloidosis: potential early indicators from a retrospective longitudinal CMR pilot study

Abstract Funding Acknowledgements Type of funding sources: None. Introduction While early diagnosis and treatment initiation is crucial in cardiac amyloidosis (CA), the diagnosis is currently mostly established in advanced stages of the disease. Cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement (LGE) provides excellent sensitivity for the diagnosis of CA. A diffuse subendocardial or transmural LGE pattern independent from coronary perfusion areas is considered characteristic of CA. Purpose While there is a distinct LGE pattern in later stages of CA, CMR characteristics during early stages are not established. In this retrospective study, we sought to identify potential early CMR indicators of CA. Methods Patients undergoing CMR at our center between 2012 and 2022 were retrospectively screened. Those with at least two CMR studies, of which only the latter demonstrated LGE characteristic for CA, were included. All patients underwent CINE and LGE imaging. Results Fifteen patient (80% male; median age 76 [73–79] at first CMR) were included in this analysis. Median time interval between the two CMR studies was 4 years. We observed differences in left ventricular morphology between the initial and follow-up CMR (IVS 15±3 vs. 17±3 mm, p = 0.003; EDV 128±40 vs. 139±39, p = 0.02). LV function was preserved and did not differ between the two CMR (EF 65±10 vs. 62±9 %, p = 0.14). While an LGE pattern characteristic for CA was present in all patients on follow-up CMR, severe left ventricular hypertrophy (IVS >14 mm in 60%), atrial LGE (67%) and focal non-ischemic LGE of the posterolateral basal LV wall (87%) were identified as highly prevalent findings during the initial CMR already. Conclusions Based on these observations, we hypothesize that the combination of certain CMR characteristics (severe septal hypertrophy, atrial LGE and LGE of the basal posterolateral LV) may help to identify CA at an early stage. Prospective studies are needed to further investigate this hypothesis.