Impact of Hypertension on Left Heart Remodelling: Echocardiography and Computed Tomography Study

BackgroundEarly recognition of left atrial (LA) and left ventricular (LV) remodelling may improve prognosis of patients with hypertension. MethodsLeft heart coupling indices were studied to investigate the adaptive effect of hypertension on cardiac remodelling. The ratio of LV to LA volumes was measured at selected phases of a cardiac cycle using computed tomography (CT) coronary angiography and transthoracic echocardiogram (TTE). A group of 180 patients was divided into Group 1 (no hypertension) and Group 2 (hypertension). Volume ratios were measured in diastasis by both CT and TTE: LVdias and LAdias. Using TTE, volumes were measured at end-diastole (LVED and LAmin)), and end-systole (LVES and LAmax). LA function and LV/LA ratios were analysed at: LVED/LAmax, LVdias/LAdias, LVED/LAmin, LVES/LAmin. ResultsThere were no differences between the age groups, LVED, and LV mass index. Compared to Group 1, Group 2 had bigger mean LV wall thickness (0.90{+/-}0.16 cm vs 0.83{+/-}0.14 cm; p=0.006), increased relative wall thickness ratio (0.39{+/-}0.09 vs 0.35{+/-}0.008, p=0.004), and more frequent concentric LV remodelling (31 vs 12, p=0.020). LA volumes were bigger in Group 2 for LAmax, LAdias, and LAmin. All LV/LA volume ratios were lower in Group 2 compared to Group 1 (LVED/LAmax 1.55{+/-}0.56 vs 1.79{+/-}0.69, p=0.010; LVED/LAmin 3.56{+/-}2.00 vs 4.59{+/-}2.56, p=0.003; LVES/LAmin 1.36{+/-}0.77, p=0.005, LVdias/LAdias (TTE) 1.75{+/-}0.61 vs 2.24{+/-}1.24, p<0.001, LVdias/LAdias (CT) 1.49{+/-}0.23 vs 1.69{+/-}0.41, p<0.001). LA reservoir function and conduit function indexed by E/e ratio was lower in Group 2. Combined TTE parameters of relative wall thickness >40, LVdias/LAdias[&le;]1.81, and indexed by E/e LA reservoir function [&le;]0.068 had the highest discriminate power to differential patients from Group 1 and Group 2 (area under the curve 0.737). ConclusionsIn hypertension, prior to the development of LV hypertrophy, adaptive remodelling is based on reduced LV/LA volume ratio, reduced indexed reservoir LA function, and increased relative LV wall thickness.