Assessment of left atrial function in patients with metabolic syndrome by four-dimensional automatic left atrial quantification.

OBJECTIVE: This study aimed at assessing the changes of left atrial (LA) volume and strain function in metabolic syndrome (MS) patients using four-dimensional automatic left atrial quantification (4D-LAQ) and exploring independent correlative factors for LA function. METHODS: A total of 110 MS patients and 70 normal controls were selected and assigned into the MS group and the control group, respectively. Echocardiogram parameters were routinely examined and the thickness of epicardial adipose tissue (EAT) were measured with a parasternal long axis of left ventricle(LV). The LA volume and strain parameters were determined using 4D-LAQ. The independent correlation factors for LA strain parameters in MS patients were investigated through linear regression analysis. RESULTS: Compared with the control group, LA volume parameters were increased in the MS group, LA strain parameters and LA emptying fraction (LAEF) were decreased (all P < 0.05). EAT thickness is associated with LA reservoir longitudinal strain (LASr), conduit longitudinal strain (LAScd), reservoir circumferential strain (LASr-c), and conduit circumferential strain (LAScd-c) (all P < 0.05). LA contraction longitudinal (LASct) and circumferential strain (LASct-c) were not statistically significant. Regression analysis results show that systolic blood pressure (SBP) and triglyceride (TG) are independent correlative factors. Intra-observer and inter-observer repeatability test showed that the LA parameters examined by 4D-LAQ had good agreement. CONCLUSIONS: 4D-LAQ is capable of effectively assessing the LA function in MS patients and providing a useful reference for clinical diagnosis. SBP and TG serve as the independent correlative factors for LA function.

Four-dimensional quantification on left atrial volume-strain in coronary heart disease patients without regional wall motion abnormalities: Correlation with the severity of coronary stenosis.

OBJECTIVE: Echocardiography is a time and cost-effective imaging modality, providing evidence of myocardial ischemia by detecting the regional wall motion abnormalities (RWMA). However, quite a few coronary heart disease (CHD) patients do not present RWMA. The left atrium (LA) plays an irreplaceable role in determining the prognosis and risk stratification of cardiovascular disease including CHD. In this present study, we intend to explore the myocardial mechanics changes of LA mainly using four-dimensional (4D) LA quantitative volume-strain in CHD patients without RWMA at rest but were confirmed by coronary angiography (CAG) and to figure out several variables of the LA that could contribute to the identification of those patients. METHODS: We prospectively enrolled 76 patients who underwent two-dimensional echocardiography (2DE), four-dimensional echocardiography (4DE), and CAG for suspected CHD but without echocardiographic visible RWMA at rest. Patients diagnosed with CHD by CAG were furtherly divided into three groups according to the extent of coronary stenosis accessed by Gensini score (GS) as the mild, moderate, and severe CHD group. Twenty-four subjects with negative CAG results served as the control group. LA end-systolic anteroposterior diameter (LAAPD) and biplane LV ejection fraction (Biplane LVEF) were measured by 2DE; LA maximum volume (LAVmax), LA minimum volume (LAVmin), LA volume at the onset of atrial contraction (LAVpreA), LAVmax index (LAVmaxI), LA ejection volume (LAEV), LA ejection fraction (LAEF) accompanied by LA longitudinal strain during reservoir phase (LASr), conduit phase (LAScd), contraction phase (LASct) and LA circumferential strain during reservoir phase (LASr_c), conduit phase (LAScd_c), contraction phase (LASct_c) were measured by 4DE automatically. We compared these parameters between groups, explored how they change and whether they are related to the CHD severity. RESULTS: LAEF, LASr_c, and LASct_c was lower in CHD group compared with the control group (p = .031, .002, .004, respectively). Pearson correlation analysis showed that LASr, LASct, LASr_c, and LASct_c negatively correlated with the GS. Additionally, LASr of patients in the severe CHD group decreased significantly compared with those in the mild CHD group, moderate CHD group, and control group, demonstrating the highest area under the receiver operating characteristic (ROC) curve (AUC) (AUC = .736 [p = .003, 95% CI .589-.884], sensitivity 67.8%, specificity 70.6%) with the cut-off value of 17.5% for predicting severe CHD patients. CONCLUSION: Four-dimensional LA strain may provide new insight into identification and management for CHD patients and correlate with CHD severity. LASr showed good sensitivity (67.8%) and specificity (70.6%) for diagnosing severe CHD individuals.