Adult Congenital Heart Centre and Centre for Pulmonary Hypertension, Royal Brompton Hospital, London, UK.
Int J Cardiol. 2011 Mar 3;147(2):219-23. doi: 10.1016/j.ijcard.2009.08.038. Epub 2009 Sep 19.
Patients with congenitally corrected transposition of the great arteries (ccTGA) have significantly reduced exercise tolerance. Progressive right ventricular (RV) dysfunction with tricuspid regurgitation (TR) and other haemodynamic lesions are common among them. We hypothesised that interaction of these factors may result in increased systemic RV filling pressure, which in turn impact on exercise capacity.
Patients with ccTGA in functional class I or II, able to perform treadmill exercise and without resting cyanosis were enrolled. All patients underwent cardiopulmonary exercise testing and transthoracic echocardiographic examination. RV filling pressure was estimated using tissue Doppler imaging (TDI) techniques by measuring early annular diastolic velocity (Ea) and the ratio of the transtricuspid inflow to the early annular diastolic velocity (E/Ea).
A total of 27 patients (mean age 41 years, 48% female) were assessed, the majority (63%) asymptomatic. Many patients had coexistent haemodynamic lesions including shunts, pulmonary stenosis, TR and systemic ventricular dysfunction. Average percentage predicted peak oxygen consumption, VE/VCO(2) slope and heart rate reserve were abnormal in this population. Patients with moderately/severely impaired exercise capacity (≤ 60% predicted peak VO(2)) had significantly higher E/Ea ratios compared to those with normal/mildly impaired exercise capacity (septal E/Ea = 17.1 ± 9.7 vs 8.8 ± 1.6 and lateral E/Ea = 11.5 ± 5.8 vs 6.6 ± 1.3, p = 0.007 and 0.01 respectively).
Reduced exercise capacity is common in adults with ccTGA even among asymptomatic patients and relates to increased RV filling pressures assessed by TDI. This index could potentially be used to optimize therapy or prognosticate adverse events in ccTGA patients.
患有先天性矫正型大动脉转位（ccTGA）的患者运动耐量明显降低。其中常见的是三尖瓣反流（TR）和其他血流动力学病变导致的右心室（RV）进行性功能障碍。我们假设这些因素的相互作用可能导致全身 RV 充盈压升高，进而影响运动能力。
纳入功能分级 I 或 II 级、能够进行跑步机运动且无静息性发绀的 ccTGA 患者。所有患者均接受心肺运动测试和经胸超声心动图检查。使用组织多普勒成像（TDI）技术通过测量瓣环舒张早期速度（Ea）和三尖瓣跨瓣血流与瓣环舒张早期速度的比值（E/Ea）来估计 RV 充盈压。
共评估了 27 例患者（平均年龄 41 岁，48%为女性），大多数（63%）无症状。许多患者存在并存的血流动力学病变，包括分流、肺动脉瓣狭窄、TR 和系统性心室功能障碍。该人群的平均预测峰值耗氧量百分比、VE/VCO2 斜率和心率储备均异常。运动能力中度/重度受损（≤预测峰值 VO2 的 60%）的患者 E/Ea 比值明显高于运动能力正常/轻度受损的患者（间隔 E/Ea=17.1±9.7 比 8.8±1.6，外侧 E/Ea=11.5±5.8 比 6.6±1.3，p=0.007 和 0.01）。
即使在无症状患者中，ccTGA 成人也常出现运动能力降低，且与 TDI 评估的 RV 充盈压升高有关。该指数可能有助于优化 ccTGA 患者的治疗或预测不良事件。
