Limb venous compliance in patients with idiopathic orthostatic intolerance and postural tachycardia.
Limb venous compliance in patients with idiopathic orthostatic intolerance and postural tachycardia.
复制标题
特发性直立不耐受和体位性心动过速患者的肢体静脉顺应性。
DOI：
10.1152/japplphysiol.00817.2001
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Risk,Marcelo
中科院分区：
文献类型：
--
作者：
Freeman,Roy;Lirofonis,Vasilios;Farquhar,WilliamB;Risk,Marcelo
静脉去神经支配和静脉汇集增加可能会导致直立性不耐受的症状。我们研究了静脉顺应性在小腿和前臂在11个直立不耐受的患者和15个年龄匹配的控制范围内的压力，在基础条件和交感神经兴奋。将放置在上臂和大腿周围的闭塞袖带充气至60 mmHg，并在1 min内放气至10 mmHg。用硅橡胶汞应变计连续测量肢体体积。顺应性计算为压力-容积曲线的数值导数。基础状态和交感神经兴奋状态下，直立不耐受组上下肢压力-容积关系均显著低于对照组（P < 0.05）。交感神经兴奋降低患者（P< 0.001）和对照组（P< 0.01）的下肢压力-容积关系。在一定压力范围内，基础状态下下肢患者的静脉顺应性显著降低（P< 0.05）。在交感神经激活状态下，患者上肢（P< 0.005）和下肢（P< 0.01）的静脉顺应性低于对照组，但在个体压力水平上无差异。交感神经激活并没有改变患者和对照组上肢和下肢的静脉顺应性。直立不耐受患者下肢静脉顺应性降低。依从性降低可能限制对立位变化的动态反应，从而导致该人群的立位不耐受症状。
Venous denervation and increased venous pooling may contribute to symptoms of orthostatic intolerance. We examined venous compliance in the calf and forearm in 11 orthostatic-intolerant patients and 15 age-matched controls over a range of pressures, during basal conditions and sympathetic excitation. Occlusion cuffs placed around the upper arm and thigh were inflated to 60 mmHg and deflated to 10 mmHg over 1 min. Limb volume was measured continuously with a mercury-in-Silastic strain gauge. Compliance was calculated as the numerical derivative of the pressure-volume curve. The pressure-volume relationship in the upper and lower extremities in the basal and sympathetically activated state was significantly lower in the orthostatic-intolerant patients (allP< 0.05). Sympathoexcitation lowered the pressure-volume relationship in the lower extremity in patients (P< 0.001) and controls (P< 0.01). Venous compliance was significantly less in patients in the lower extremity in the basal state over a range of pressures (P< 0.05). Venous compliance was less in patients compared with controls in the upper (P< 0.005) and lower extremities (P< 0.01) in the sympathetically activated state, but there were no differences at individual pressure levels. Sympathetic activation did not change venous compliance in the upper and lower extremity in patients and controls. Patients with orthostatic intolerance have reduced venous compliance in the lower extremity. Reduced compliance may limit the dynamic response to orthostatic change and thereby contribute to symptoms of orthostatic intolerance in this population group.