Left atrial function: Correlation with left ventricular function and contractile reserve in patients with hypertension.

Abstract

Alterations in left atrial (LA) and left ventricular (LV) function have been documented in hypertensive patients. However, the correlation of LA with LV functional changes has not been established. Using normotensive controls, we examined LA functional changes in hypertensive patients by strain deformation analysis, and their relationship to LV functional changes including contractile reserve (CR). One hundred and sixteen patients (61 men, aged 57.6±9.1years, 67 with hypertension) underwent dobutamine echocardiography. Patients with significant coronary or valvular disease, previous myocardial infarction or coronary revascularization, and diabetes were excluded. LA reservoir (Ɛs), conduit (Ɛe), and atrial contractile (Ɛa) strain were measured at rest. LV global longitudinal strain (GLS) and ejection fraction (LVEF) were measured at rest and at low-dose dobutamine. LV CR was calculated as the difference in GLS and LVEF between the low dose and their corresponding resting values. Hypertensive patients, compared with controls, had significantly impaired LA Ɛs (30.7±3.9% vs 42.4±4.9%), Ɛe (16.2±4.1% vs 22.5±5.5%), and Ɛa (14.5±4.1% vs 19.9±5.0%, all P<.001) strain. All LA phasic strain correlated with LV GLS at rest, at low-dose dobutamine, and LV CR. There was no correlation between LA strain and LVEF or LV CR assessed by LVEF. LV GLS and LAVImax were the strongest independent determinants for LA Ɛs/Ɛe and LA Ɛa, respectively. Compared to controls, hypertensive patients had impaired LA strain, which correlated with LV GLS and CR. LV GLS and LAVImax were the strongest independent determinants for LA Ɛs/Ɛe and LA Ɛa, respectively, independent of BP and LVMi.