Deterioration of Myocardial Global Longitudinal Strain and Its Relationship with Arterial Stiffness in Patients with Cardiac Amyloidosis: A Six-Month Follow-Up

Background: Cardiac amyloidosis (CA) is a progressive disorder characterized by amyloid fibril deposition in the heart, leading to heart failure and arrhythmias. Arterial stiffness, assessed by pulse wave velocity (PWV), is recognized as an adverse consequence of amyloidosis, yet its progression and relationship with myocardial dysfunction remain inadequately explored. This study examines the progression of PWV and its potential association with the deterioration of global longitudinal strain (GLS) in CA patients over a 6-month follow-up period. Methods: This prospective study enrolled 31 patients who were diagnosed with CA, including both the immunoglobulin light chain (AL) and transthyretin (ATTR) forms. All participants underwent a full echocardiographic study and PWV measurements (carotid-femoral [c-f] and carotid-radial [c-r] PWV) at baseline and 6-month follow-up. Age- and sex-matched individuals with similar cardiovascular risk factors were included as a control group. Results: In the CA group, the left ventricular mass index (LVMI) increased significantly from 119.4 +/- 52.1 to 124 +/- 53.2 g/m(2) (p = 0.002). Both c-f and c-r PWV showed significant increases at the 6-month follow-up (p < 0.001 and p = 0.005, respectively). The GLS deteriorated significantly from -14 +/- 4.4% to -12.8 +/- 4.9% (p = 0.018). No significant changes were observed in the control group. A weak correlation (r = 0.3; p = 0.095) was found between increases in PWV and GLS deterioration. Conclusions: Both arterial stiffness and myocardial dysfunction worsen rapidly in CA patients. However, the weak correlation between PWV and GLS suggests that they may evolve through independent mechanisms, necessitating further research to understand their complex interplay in CA.