The left ventricular mechanical dispersion as a marker of disease severity in transthyretin cardiac amyloidosis

Transthyretin amyloidosis (ATTR) is a fatal disorder, thus early detection of cardiac involvement is crucial for improved clinical outcomes. This study investigated the utility of left ventricular (LV) speckle-tracking-derived mechanical dispersion as a potential marker for the assessment of cardiac amyloidosis (CA) in patients with ATTR and their first-degree relatives. This prospective, single-centre study enrolled 100 adults from 2020 to 2024 (ClinicalTrials NCT05814380). Participants underwent clinical assessment, genetic testing, and [^99mTc]Tc-DPD SPECT/CT. Global longitudinal strain (GLS) and mechanical dispersion were evaluated using speckle-tracking echocardiography. Patients with ATTR CA exhibited significantly impaired GLS and increased mechanical dispersion (p < 0.001). Mechanical dispersion exhibited correlations with age, New York Heart Association class, LV mass index, E/E', LV ejection fraction, GLS, levels of N-terminal pro-brain natriuretic peptide and Perugini grade (p < 0.05 for all). In univariable Cox regression, mechanical dispersion (Hazard ratio (HR) = 1.03, 95% confidence intervals (CI) 1.01-1.06, p = 0.004), normalised to heart rate mechanical dispersion (HR = 1.43, 95% CI 1.14-1.81, p = 0.002) were significant predictors of all-cause mortality. In our study increased mechanical dispersion was associated with advanced disease stages and mortality. These findings suggest that it may serve as a marker of ATTR CA.Registration: ClinicalTrials.gov Identifier: NCT05814380.