Arterial-myocardial coupling in primary light chain amyloidosis: A prospective observational study of vascular involvement.

Primary light chain (AL) amyloidosis is a rare but lethal systemic disorder. Prior work suggests that vascular involvement may independently affect survival. Mechanistic data are needed to clarify its clinical role. We sought to explore vascular-cardiac interactions by examining associations between vascular and cardiac markers. We recruited 151 newly-diagnosed patients with AL amyloidosis who underwent peripheral vascular assessment including flow-mediated dilation (FMD) and pulse wave velocity (PWV). Transthoracic echocardiography was performed in all patients, and cardiac magnetic resonance (CMR) in a subgroup (n = 59). Ventricular-arterial coupling was assessed using PWV/global longitudinal strain (GLS), central systolic blood pressure (CSBP)/GLS, and tricuspid annular plane systolic excursion (TAPSE)/right ventricular systolic pressure (RVSP). Vascular and hemodynamic markers were associated with cardiac involvement, including left ventricle (LV) and right ventricle (RV) systolic and diastolic function, LV hypertrophy and CMR parameters (T2 and late gadolinium enhancement). Markers of vasodilation and low peripheral resistance correlated with more severe cardiac involvement. Low peripheral and central blood pressure and pressure-strain indices predicted worse survival. Peripheral vascular dysfunction was linked to adverse cardiac structure and function in AL amyloidosis. These observational findings suggest that arterial-myocardial uncoupling parallels disease severity and serves as a marker of advanced cardiovascular involvement highlighting its prognostic significance.