Dubach P, Myers J, Dziekan G, Goebbels U, Reinhart W, Muller P, Buser P, Stulz P, Vogt P, Ratti R
Cardiology Department, Kantonsspital, Chur, Switzerland.
J Am Coll Cardiol. 1997 Jun;29(7):1591-8. doi: 10.1016/s0735-1097(97)82540-5.
The aim of this study was to evaluate the effects of high intensity exercise training on left ventricular function and hemodynamic responses to exercise in patients with reduced ventricular function.
Results of studies on central hemodynamic adaptations to exercise training in patients with chronic heart failure have been contradictory, and some research has suggested that training causes further myocardial damage in these patients after a myocardial infarction.
Twenty-five men with left ventricular dysfunction after a myocardial infarction or coronary artery bypass graft surgery were randomized to an exercise training group (mean age +/- SD 56 +/- 5 years, mean ejection fraction [EF] 32 +/- 7%, n = 12) or a control group (mean age 55 +/- 7 years, mean EF 33 +/- 6%, n = 13). Patients in the exercise group performed 2 h of walking daily and four weekly sessions of high intensity monitored stationary cycling (40 min at 70% to 80% peak capacity) at a residential rehabilitation center for a period of 2 months. Ventilatory gas exchange and upright hemodynamic measurements (rest and peak exercise cardiac output; pulmonary artery, wedge and mean arterial pressures; and systemic vascular resistance) were performed before and after the study period.
Maximal oxygen uptake (VO2max) increased by 23% after 1 month of training, and by an additional 6% after month 2. The increase in VO2max in the trained group paralleled an increase in maximal cardiac output (12.0 +/- 1.8 liters/min before training vs. 13.7 +/- 2.5 liters/min after training, p < 0.05), but maximal cardiac output did not change in the control group. Neither stroke volume nor hemodynamic pressures at rest or during exercise differed within or between groups. Rest left ventricular mass, volumes and EF determined by magnetic resonance imaging were unchanged in both groups.
High intensity exercise training in patients with reduced left ventricular function results in substantial increases in VO2max by way of an increase in maximal cardiac output combined with a widening of maximal arteriovenous oxygen difference, but not changes in contractility. Training did not worsen hemodynamic status or cause further myocardial damage.
本研究旨在评估高强度运动训练对心室功能降低患者左心室功能及运动时血流动力学反应的影响。
关于慢性心力衰竭患者运动训练中心脏血流动力学适应性的研究结果相互矛盾，一些研究表明，训练会在心肌梗死后使这些患者的心肌损伤进一步加重。
25名心肌梗死或冠状动脉搭桥手术后出现左心室功能障碍的男性被随机分为运动训练组（平均年龄±标准差56±5岁，平均射血分数[EF]32±7%，n = 12）或对照组（平均年龄55±7岁，平均EF 33±6%，n = 13）。运动组患者在一家住宅康复中心每天步行2小时，并每周进行4次高强度的监测下的固定自行车运动（在70%至80%的峰值能力下进行40分钟），为期2个月。在研究期前后进行通气气体交换和直立位血流动力学测量（静息和运动峰值心输出量；肺动脉、楔压和平均动脉压；以及全身血管阻力）。
训练1个月后，最大摄氧量（VO2max）增加了23%，第2个月后又增加了6%。训练组VO2max的增加与最大心输出量的增加平行（训练前为12.0±1.8升/分钟，训练后为13.7±2.5升/分钟，p < 0.05），但对照组的最大心输出量没有变化。组内或组间静息或运动时的每搏输出量和血流动力学压力均无差异。两组通过磁共振成像测定的静息左心室质量、容积和EF均未改变。
左心室功能降低的患者进行高强度运动训练可通过增加最大心输出量并扩大最大动静脉氧差，使VO2max大幅增加，但收缩性无变化。训练并未使血流动力学状态恶化或导致进一步的心肌损伤。
