Association of Nighttime Systolic Blood Pressure With Left Atrial-Left Ventricular–Arterial Coupling in Hypertension

OBJECTIVE: Hypertension (HT) induces left atrial (LA) and left ventricular (LV) dysfunction, and an increase in arterial stiffness. In this study, we investigated the association between LA-LV–arterial coupling and nighttime systolic blood pressure (BP) as well as BP circadian rhythm in essential hypertension. METHODS: We enrolled 290 HT patients. All subjects were evaluated by 2- dimensional speckle tracking echocardiography (2DSTE), ambulatory 24 h BP monitoring (ABPM), and brachial–ankle pulse wave velocity (PWV). According to BP patterns, these patients were divided into two groups, which included dippers (n = 111), patients with a >10% reduction in BP at nighttime; non-dippers (n = 179), patients with a <10% reduction in BP at nighttime. 2D-STE based LA and LV strains were studied and the following parameters were measured, LV global longitudinal strain (GLS), LA reservoir strain (LA(S−S)), LA conduit strain (LA(S−E)), and LA booster pump strain (LA(S−A)). LA stiffness index (LASI) defined as the ratio of E/e′ to LA(S−S), and PWV-to-GLS ratio (PWV/GLS) were calculated to reflect LA-LV–arterial coupling. Furthermore, we also explored the correlation between LASI (or PWV/GLS) and ambulatory blood pressure indexes. RESULTS: Left atrial stiffness index was significantly higher in non-dippers [0.29 (0.21, 0.41)] than in dippers [0.26 (0.21, 0.33)] (P < 0.05). PWV/GLS was significantly higher in non-dippers [−80.9 (−69.3, −101.5)] than in dippers [−74.2 (−60.2, −90.6)] (P < 0.05). LA(S−S), LA(S−E), LA(S−A),and LV GLS were significantly lower in non-dippers than in dippers (P < 0.05). Multivariate linear regression analysis revealed that nighttime systolic BP was independently correlated with LASI and PWV/GLS, even adjusted for multiple clinical risk factors, LVMI, and LVEF. CONCLUSIONS: The dipping pattern of BP was related to the abnormalities of myocardial mechanics and LA-LV–arterial coupling. However, absolute nocturnal systolic BP value maybe more important than BP circadian profile in the progression of abnormal LA-LV–arterial coupling.