Gullestad L, Myers J, Noddeland H, Bjørnerheim R, Djøseland O, Hall C, Gieran O, Kjekshus J, Simonsen S
Heart Transplant Unit, Rikshospitalet University Hospital, Oslo, Norway.
J Heart Lung Transplant. 1996 Mar;15(3):304-13.
A gradual accommodation to increasing exercise loads has been recommended for exercise testing in denervated posttransplantation heart recipients. However, how the exercise protocol influence the hemodynamic, gas exchange, and hormonal response to exercise in this not been studied.
Nine heart transplant recipients tests incremental maximal bicycle ergometry tests in random order. Exercise stages of 1 and 3 minute durations were compared with matched work rate increments ranging between 30 and 40 W. Expiratory gas was measured continuously and arterial blood was sampled at each of the matched work rates.
Total exercise duration was 6.4 +/- and 15.3 +/- 0.7 minutes for the 1-minute and 3-minute protocols, respectively. Maximal workload was significantly higher during the 1-minute versus the 3-minute protocol (238 +/- 9 versus 200 +/- 11 W, p < 0.001), but maximal oxygen uptake was not significantly different (25.5 +/- 1.1 versus 26.5 +/- 1.2 ml. min-1.kg-1). Hemodynamic, metabolic, and some hormonal parameters showed marked differences between the two protocols, with significantly higher responses observed during the 3-minute protocol for heart rate, ventilation, lactate, atrial natriuretic factor, and growth hormone. Catecholamine (epinephrine and norepinephrine) and insulin responses did not differ between the two tests. If expressed as a relative exercise intensity (percentage of maximal oxygen uptake) no differences in hormonal responses were observed between the two protocols, except for growth hormone response which remained higher during the 3-minute protocol.
Although maximal oxygen uptake was independent of the exercise protocol in these heart transplant recipients, the exercise protocol has a major influence on the hormonal and metabolic response. The delayed response observed for oxygen uptake and hormonal responses suggests a significant physiologic lag time during the more rapidly incremental protocol. These differences should be taken into account when exercise is used as a method to evaluate the heart transplant recipient.
对于去神经支配的心脏移植受者进行运动测试时，建议逐渐适应增加的运动负荷。然而，运动方案如何影响该人群运动时的血流动力学、气体交换和激素反应尚未得到研究。
9名心脏移植受者以随机顺序进行递增式最大运动平板试验。将持续1分钟和3分钟的运动阶段与30至40瓦的匹配工作率增量进行比较。连续测量呼气末气体，并在每个匹配工作率下采集动脉血样。
1分钟和3分钟方案的总运动时间分别为6.4±0.7分钟和15.3±0.7分钟。1分钟方案的最大工作量显著高于3分钟方案（238±9瓦对200±11瓦，p<0.001），但最大摄氧量无显著差异（25.5±1.1对 vs 26.5±1.2 ml·min-1·kg-1）。两种方案在血流动力学、代谢和一些激素参数方面存在显著差异，在3分钟方案中，心率、通气、乳酸、心房利钠因子和生长激素的反应显著更高。两种测试中儿茶酚胺（肾上腺素和去甲肾上腺素）和胰岛素反应无差异。如果以相对运动强度（最大摄氧量的百分比）表示，除了生长激素反应在3分钟方案中仍然较高外，两种方案之间的激素反应没有差异。
虽然在这些心脏移植受者中最大摄氧量与运动方案无关，但运动方案对激素和代谢反应有重大影响。在更快递增的方案中观察到的摄氧量和激素反应的延迟表明存在显著的生理滞后时间。在将运动作为评估心脏移植受者的方法时，应考虑这些差异。
