Background: Left atrial (LA) function is crucial for assessing left ventricular filling in various cardiovascular conditions. Cardiac Amyloidosis (CA) is characterized by atrial myopathy and LA function impairment, with diastolic dysfunction up to restrictive filling pattern, leading to progressive heart failure and arrhythmias. This study evaluates LA function and deformation using speckle tracking echocardiography (STE) in patients with CA compared to a cohort of patients with sarcomeric Hypertrophic Cardiomyopathy (HCM) and a control group. Methods: We conducted a retrospective, observational study (from January 2019 to December 2022) including a total of 100 patients: 33 with ATTR-CA, 34 with HCMs, and 33 controls. Clinical evaluation, electrocardiograms, and transthoracic echocardiography were performed. Echocardiogram images were analyzed in post-processing using EchoPac software for LA strain quantification, including LA-reservoir, LA-conduit, and LA-contraction strain. Results: The CA group exhibited significantly impaired LA function compared to HCMs and control groups, with LA-reservoir median values of −9%, LA-conduit −6.7%, and LA-contraction −3%; this impairment was consistent even in the CA subgroup with preserved ejection fraction. LA strain parameters correlated with LV mass index, LA volume index, E/e’, and LV-global longitudinal strain and were found to be associated with atrial fibrillation and exertional dyspnea. Conclusions: LA function assessed by STE is significantly impaired in CA patients compared to HCMs patients and healthy controls. These findings highlight the potential supportive role of STE in the early detection and management of the disease.

Background: The pathophysiological impact of systemic vascular resistance (SVR) and pressure–strain loop-derived global myocardial work index (GWI) in hypertrophic cardiomyopathy (HCM) and transthyretin cardiac amyloidosis (ATTR) has been randomly investigated. Methods: Both SVR and GWI were assessed in outpatients consecutively referred at two Italian cardiology departments for heart failure with preserved left ventricular ejection fraction (LVEF), affected by either nonobstructive HCM or wild-type ATTR. Based on relevant cross-tabulations, the patients were gathered into 4 functional classes according to cut-off values of 1440 dyne/s/cm⁻⁵ for SVR, and 1576 mm Hg% for GWI, as suggested by previous studies. Results: A total of 60 patients, 30 in each group, aged 61 ± 16 years, with 78% males, were studied. HCM patients were younger than those with ATTR and in a better clinical condition (23% HCM vs. 77% ATTR were NYHA class II-III, p < 0.001). Overall, 51 patients (85%) showed a high SVR, 21/30 HCM (70%), and 30 ATTR (100%) (p < 0.005). Both SVR and GWI (expressions of ventricular–arterial coupling) were impaired in 43% of HCM patients (showing greater LV concentric hypertrophy) and 93% of ATTR patients (in advanced NYHA functional class) (p < 0.001). Conclusions: A substantial percentage of present study population showed impaired SVR and/or GWI, despite preserved LVEF. The proposed classification may shed further light on the pathophysiological and clinical characteristics of such hypertrophic phenotypes.

The impact of systemic vascular resistance (SVR) in hypertrophic (HCM) and amyloid cardio-myopathies has been seldom investigated. We studied pressure-strain loop derived myocardial work (MW) indices and SVR in patients with either sarcomere HCM or wild type transthyretin cardiac amyloidosis (ATTR), presented with heart failure and preserved left ventricular ejection fraction (HFpEF) at the outpatient cardiology units at Messina and Catania University Hospitals (Italy). Patients were in sinus rhythm and needed to have good transthoracic ultrasound imaging quality to undergo transthoracic strain-echocardiography. Other than conventional parameters, SVR and GWI (global work index) were measured. Based on cross-tabulation (a way to assess the ventricular-arterial coupling), the patients were then classified in 4 classes according to the cut-off values suggested by previous studies of 1,440 dyne/s/cm-5 for SVR (Stefadouros et al., 1973) and 1576 mm Hg% for GWI (Olsen et al., 2022). Sixty patients, 30 in each group, aged 61±16 years, 78% males, were studied. HCM were younger than ATTR patients and in a better clinical status (23% HCM vs 77% ATTR were NYHA class 3, p<0.001). Overall, 51 patients (85%) showed high SVR, of whom 21 were HCM (70%) and 30 ATTR (100%) (p<0.005). Both, SVR and GWI were impaired (the poorest class C) in 43% HCM patients (with greater left ventricular concentric hypertrophy) vs 93% of ATTR patients (in advanced NYHA class) (p<0.001). In conclusion, assessing SVR and GWI in HFpEF patients with HCM or ATTR can help clinicians to interpret the pathophysiological and clinical features of such complex diseases.