EARLY AND CONTINUOUS DETECTION OF LEFT ATRIAL PHASIC DYSFUNCTION IN THE PROGRESSION OF HYPERTENSIVE CARDIAC REMODELING

Abstract

Objective: Objective: The left atrium (LA) modulates left ventricular (LV) filling and cardiovascular performance with its reservoir, conduit, and booster pump functions. We used two dimensional speckle tracking echocardiography (2DSTE)-based strain and strain rate to evaluate LA mechanics in hypertensive patients with or without LA/LV structural remodeling. Design and method: Design and Method: We enrolled 30 healthy controls (Group I) and 302 HT patients, and we divided HT patients according to LV and LA structural remodeling. Group II (n = 101), HT without LVH and LA volume index (LAVI) < 28 mL/m2; Group III (n = 82), HT without LVH and LAVI > 28 mL/m2; Group IV (n = 98), HT with LVH and E/e‘ < 13; Group V (n = 21), HT with LVH and E/e‘ > 13. The strain and strain rate images were studied, and the following parameters were measured: LA reservoir strain and strain rate (LAS-S, LASR-S), LA conduit strain and strain rate (LAS-E and LASR-E), LA booster strain and strain rate (LAS-A and LASR-A). LA stiffness index (LASI) was defined as the ratio of E/e‘ to LAS-S. Results: Results: LASI was significantly higher in Group II than Group I (p < 0.05), and further increased in Group III and IV. LASI is the highest in Group V (p < 0.001 vs Group I and II, p < 0.05 vs Group III and IV). Generally, All strain and strain rate parameters, including LAS-S, LASR-S, LAS-E, LASR-E, LAS-A and LASR-A, gradually and significantly decreased from Group I to Group V. We also explored the correlation between LASI and cardiovascular risk factors as well as the other markers of TOD in HT. LASI was correlated with age, diabetes, hemoglobin A1c, systolic blood pressure, BMI, LVMI, Ma/Cre, carotid IMT, PWV, Triglycerides and eGFR. Multivariate regression analysis revealed that age, BMI, PWV and Ma/Cre were independent factors related to LASI. Conclusions: Conclusions: The abnormality of LA mechanics precedes LA enlargement and LVH in HT, and strain-derived LA phasic function declined further along with LA and LV remodeling and diastolic dysfunction. LASI can be identified as a detective biomarker of left cardiac remodeling and diastolic dysfunction in HT.