Characteristics of cardiovascular morphology and function in the high-normal subset of hypertension defined by JNC-VI recommendations

A cross-sectional study was conducted to compare the morphological and func tional characteristics of the cardiovascular system among subgroups of hype rtension defined by the JNC-VI recommendations. One hundred and sixteen sub jects (normotensives and unmedicated hypertensives: 49 +/- 10 yr) were clas sified into 4 groups based on the criteria of JNC-VI: normotensive (NOR: n = 38), high-normal blood pressure (HN: n = 16), stage 1 hypertensive (SI: n = 28), and stage 2 to 3 hypertensive (SII-III: n = 34). Ultrasonographic e xaminations of the heart and carotid artery were performed in all subjects, and the following parameters were obtained: left ventricular mass index (L VMI), relative wall thickness at end-diastole (RWTd), cardiac diastolic fun ction (A/E), common carotid artery diameter(CAD), intimal media thickness o f the common carotid artery (IMT), and distensibility of the common carotid artery (Distens). RWTd, A/E, and IMT in SI (RWTd, 0.41 +/- 0.07; A/E, 1.21 +/- 0.41; IMT, 0.69 +/- 0.17 mm) and SII-III patients (0.40 +/- 0.08, 1.38 +/- 0.33, 0.80 +/- 0.21 mm) were larger than those in NOR patients (0.33 /- 0.03, 0.86 +/- 0.21, 0.56 +/- 0.10 mm) (p < .01). Furthermore, LVMI in S II-III (135.5 +/- 35.5 g/m(2)) patients was larger than that in NOR patient s (99.4 +/- 17.5 g/m(2)) (p < .05). RWTd in HN patients (0.37 +/- 0.06) was significantly higher than that in NOR patients (p < .05). A/E tended to be larger in HN than in NOR patients (p < 0.1). In the normotensives, no sign ificant difference in any of the parameters was detected between those with optimal (n = 19) and normal (n = 19) blood pressure. Thus, both morphologi cal and functional changes were associated with elevation of blood pressure . Cardiac morphological adaptation and functional impairment were present e ven in subjects with high-normal blood pressure level, while there were no significant differences between the normal and optimal subsets.