Shafer K M, Janssen L, Carrick-Ranson G, Rahmani S, Palmer D, Fujimoto N, Livingston S, Matulevicius S A, Forbess L W, Brickner B, Levine B D
Boston Children's Hospital, Department of Cardiology, Boston, MA, USA.
University of Texas Southwestern Medical Center, Dallas, TX, USA.
J Physiol. 2015 Jun 1;593(11):2447-58. doi: 10.1113/JP270280.
Patients with transposition of the great arteries (TGA) and systemic right ventricles have premature congestive heart failure; there is also a growing concern that athletes who perform extraordinary endurance exercise may injure the right ventricle. Therefore we felt it essential to determine whether exercise training might injure a systemic right ventricle which is loaded with every heartbeat. Previous studies have shown that short term exercise training is feasible in TGA patients, but its effect on ventricular function is unclear. We demonstrate that systemic right ventricular function is preserved (and may be improved) in TGA patients with exercise training programmes that are typical of recreational and sports participation, with no evidence of injury on biomarker assessment. Stroke volume reserve during exercise correlates with exercise training response in our TGA patients, identifying this as a marker of a systemic right ventricle (SRV) that may most tolerate (and possibly even be improved by) exercise training.
We aimed to assess the haemodynamic effects of exercise training in transposition of the great arteries (TGA) patients with systemic right ventricles (SRVs). TGA patients have limited exercise tolerance and early mortality due to systemic (right) ventricular failure. Whether exercise training enhances or injures the SRV is unclear. Fourteen asymptomatic patients (34 ± 10 years) with TGA and SRV were enrolled in a 12 week exercise training programme (moderate and high-intensity workouts). Controls were matched on age, gender, BMI and physical activity. Exercise testing pre- and post- training included: (a) submaximal and peak; (b) prolonged (60 min) submaximal endurance and (c) high-intensity intervals. Oxygen uptake (V̇O2; Douglas bag technique), cardiac output (Q̇c, foreign-gas rebreathing), ventricular function (echocardiography and cardiac MRI) and serum biomarkers were assessed. TGA patients had lower peak V̇O2, Q̇c, and stroke volume (SV), a blunted Q̇c/V̇O2 slope, and diminished SV response to exercise (SV increase from rest: TGA = 15.2%, controls = 68.9%, P < 0.001) compared with controls. After training, TGA patients increased peak V̇O2 by 6 ± 8.5%, similar to controls (interaction P = 0.24). The magnitude of SV reserve on initial testing correlated with Q̇c training response (r = 0.58, P = 0.047), though overall, no change in peak Q̇c was observed. High-sensitivity troponin T (hs-TnT) and N-terminal prohormone of brain naturetic peptide (NT pro-BNP) were low and did not change with acute exercise or after training. Our data show that TGA patients with SRVs in this study safely participated in exercise training and improved peak V̇O2. Neither prolonged submaximal exercise, nor high-intensity intervals, nor short-term exercise training seem to injure the systemic right ventricle.
大动脉转位（TGA）和体循环右心室患者会过早出现充血性心力衰竭；人们也越来越担心进行超常耐力运动的运动员可能会损伤右心室。因此，我们认为有必要确定运动训练是否会损伤每次心跳都承受负荷的体循环右心室。先前的研究表明，短期运动训练在TGA患者中是可行的，但其对心室功能的影响尚不清楚。我们证明，对于参与休闲和体育活动的典型运动训练计划的TGA患者，体循环右心室功能得以保留（甚至可能得到改善），生物标志物评估未显示损伤迹象。运动期间的每搏输出量储备与我们的TGA患者的运动训练反应相关，将其确定为最能耐受（甚至可能通过）运动训练的体循环右心室（SRV）的标志物。
我们旨在评估运动训练对患有体循环右心室（SRV）的大动脉转位（TGA）患者的血流动力学影响。TGA患者由于体循环（右）心室衰竭，运动耐力有限且早期死亡率较高。运动训练是增强还是损伤SRV尚不清楚。14名无症状的TGA和SRV患者（34±10岁）参加了为期12周的运动训练计划（中等强度和高强度锻炼）。对照组在年龄、性别、BMI和身体活动方面进行了匹配。训练前后的运动测试包括：（a）次最大和峰值测试；（b）延长（60分钟）次最大耐力测试；（c）高强度间歇测试。评估了摄氧量（V̇O2；道格拉斯袋技术）、心输出量（Q̇c，外呼吸法）、心室功能（超声心动图和心脏磁共振成像）以及血清生物标志物。与对照组相比，TGA患者的峰值V̇O2、Q̇c和每搏输出量（SV）较低，Q̇c/V̇O2斜率变钝，运动时SV反应减弱（静息时SV增加：TGA = 15.2%，对照组 = 68.9%，P < 0.001）。训练后，TGA患者的峰值V̇O2增加了6±8.5%，与对照组相似（交互作用P = 0.24）。初始测试时的SV储备幅度与Q̇c训练反应相关（r = 0.58，P = 0.047），不过总体而言，未观察到峰值Q̇c有变化。高敏肌钙蛋白T（hs-TnT）和脑钠肽N末端前体激素（NT pro-BNP）较低，且急性运动或训练后未发生变化。我们的数据表明，本研究中的患有SRV的TGA患者安全地参与了运动训练并提高了峰值V̇O2。无论是延长的次最大运动、高强度间歇运动，还是短期运动训练，似乎都不会损伤体循环右心室。
