Early left atrial mechanics and volume abnormalities in subjects with prehypertension: a real time three-dimensional echocardiography study.

The aim of this study was to evaluate left atrial (LA) volume and mechanical functions by real time three-dimensional echocardiography (RT3DE) in prehypertensive subjects. The study included 54 (34 male and 20 female) prehypertensive subjects and 36 (14 male and 22 female) healthy control subjects. Transthoracic echocardiography and RT3DE were performed in all patients. Interventricular septum thickness and isovolumetric relaxation time were significantly higher in prehypertensives than in controls (10.7 ± 0.7 vs. 10.1 ± 0.8 P = 0.001 and 89.9 ± 10 vs. 82.4 ± 11 P = 0.002, respectively). LA maximum volume, volume before atrial contraction, total and active stroke volume, total and active emptying fractions, expansion index, and LA max volume index were significantly higher in prehypertensives when compared with controls (P < 0.0001 for all). However, the passive emptying fraction was significantly lower in prehypertensives than controls (45.7 ± 5.6 vs. 48.6 ± 4.1, P = 0.006), and the minimum LA volume between the two groups was similar. The main finding of this study was that although LA volume and LA active systolic functions were significantly increased in prehypertensive people, there was a reduction in passive LA systolic functions. These parameters may be important in showing hemodynamic and structural changes in cardiac tissue caused by prehypertension.