Cavero P G, Sudhir K, Galli F, DeMarco T, Keith F, Chatterjee K
Cardiovascular Research Institute, University of California at San Francisco 94143.
Am Heart J. 1994 Jun;127(6):1581-7. doi: 10.1016/0002-8703(94)90389-1.
The objective of this study was to examine peripheral vascular function before and after cardiac transplantation and to assess the effect of immunosuppressive therapy on peripheral vascular reactivity. Peripheral vascular function abnormalities present in congestive heart failure may be reversed with cardiac transplantation, but immunosuppressive therapy may alter these changes in the peripheral vasculature. Venous occlusion plethysmography was used to study peripheral vascular function in nine patients with severe congestive heart failure who underwent cardiac transplantation. Forearm blood flow and forearm vascular resistance were measured in patients with congestive heart failure in response to cold stimulation, maximal hyperemia, and hand grip exercise (1) before transplantation; (2) 24 to 36 hours posttransplantation before the commencement of cyclosporine; (3) 6 to 8 days posttransplantation in the presence of therapeutic cyclosporine levels; and (4) 6 weeks posttransplantation. Venous capacitance was also measured. After cardiac transplantation, mean arterial pressure increased and remained elevated. Forearm blood flow initially increased after transplantation but subsequently decreased with cyclosporine. Cold-induced reflex sympathetic activation decreased immediately after transplantation but was significantly enhanced with cyclosporine. The maximal vasodilatory response following ischemic cuff occlusion and with 5 minutes of isometric hand grip exercise increased significantly after transplantation and remained improved at 6 weeks. Thus after cardiac transplantation, peripheral vasodilator function improves and is not altered by cyclosporine. However, with cyclosporine therapy resting forearm vascular resistance increases and reflex sympathetic vasoconstriction is enhanced, suggesting that cyclosporine may potentiate adrenergic-mediated peripheral vasoconstriction and thus may contribute to posttransplant hypertension.
本研究的目的是检查心脏移植前后的外周血管功能，并评估免疫抑制治疗对外周血管反应性的影响。充血性心力衰竭中存在的外周血管功能异常可能会通过心脏移植得到逆转，但免疫抑制治疗可能会改变外周血管系统的这些变化。静脉阻塞体积描记法用于研究9例接受心脏移植的严重充血性心力衰竭患者的外周血管功能。在充血性心力衰竭患者中，于移植前、移植后24至36小时开始使用环孢素之前、移植后6至8天处于治疗性环孢素水平时以及移植后6周，测量前臂血流量和前臂血管阻力，以响应冷刺激、最大充血和握力运动。还测量了静脉容量。心脏移植后，平均动脉压升高并持续升高。移植后前臂血流量最初增加，但随后随着环孢素的使用而减少。移植后冷诱导的反射性交感神经激活立即降低，但随着环孢素的使用而显著增强。缺血袖带阻塞和5分钟等长握力运动后的最大血管舒张反应在移植后显著增加，并在6周时仍保持改善。因此，心脏移植后，外周血管舒张功能改善且不受环孢素影响。然而，使用环孢素治疗时，静息前臂血管阻力增加，反射性交感神经血管收缩增强，提示环孢素可能增强肾上腺素能介导的外周血管收缩，从而可能导致移植后高血压。
