[Hemodynamics of elderly hypertensives].
To study the hemodynamic characteristics of elderly hypertensives, elderly subjects (greater than or equal to 65 years old) were divided into normotensives (NT, n = 15), borderline hypertensives (BH, n = 10) and established hypertensives (EH, n = 20) and compared each group with similarly divided middle aged subjects (greater than or equal to 35 years old, less than 65 years old), NT (n = 23), BH (n = 112) and EH (n = 79). An attempt was also made to clarify what factor is most important regarding left ventricular hypertrophy (LVH) in elderly hypertensives. The results showed that with advancing age, cardiac output and stroke volume decrease (p less than 0.05), total peripheral resistance and volume-elasticity index increase (p less than 0.05), daily lability of systolic pressure increases and the baroreceptor slope increases. Furthermore, almost all of these tendencies are exacerbated by hypertension (p less than 0.05). With advancing age, pressure response to infused noradrenaline is enhanced (p less than 0.05), but on exercise, there are wide variations in each group and no distinct differences were observed. Echocardiographic examinations revealed LVH in 50% of elderly hypertensives. There were no apparent differences between both groups with or without LVH in their family and personal histories of hypertension, resting hemodynamics, hormonal examinations and hypertensive complications other than the heart. However, on exercise, the pressure response was more enhanced in the group with LVH than in the group without LVH (p less than 0.05). There was no significant correlation between resting systolic pressure (SBP) and left ventricular mass index (LVMi), but, there was relatively good correlation (r = 0.563, p less than 0.05) between SBP at peak exercise and LVMi. Using delta SBP/delta HR as a parameter of pressure responsibility on exercise test, 9 out of 10 patients with LVH showed above 1.0, while all of 10 patients without LVH showed under 1.0. Pressure response to infused noradrenaline seems to be more enhanced in the group with LVH than in the group without LVH. It was concluded that enhanced pressure responsiveness to recurring stress might induce or at least sustain LVH in hypertensives, due to enhanced alpha-adrenoceptor responsiveness.
Yamada
K
K
Third Department of Internal Medicine, Chiba University.
D000328:Adult; D000367:Age Factors; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D006332:Cardiomegaly / Q000209:etiology; D005080:Exercise Test; D006439:Hemodynamics; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology*; D008875:Middle Aged; D009638:Norepinephrine
D009638:Norepinephrine