Luo Shuhua, Li Jianhua, Yang Dan, Zhou Yaxin, An Qi, Chen Yucheng
Department of Cardiac Surgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China.
Department of Cardiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China.
Interact Cardiovasc Thorac Surg. 2017 May 1;24(5):755-761. doi: 10.1093/icvts/ivw424.
The relationship between exercise capacity and right ventricular (RV) components function in repaired tetralogy of Fallot patients with severely dilated right ventricles is poorly understood. The aim of this study was to characterize the exercise capacity and its relationship to RV global and components function in repaired tetralogy of Fallot patients with RV end-diastolic volume index >150 ml/m 2 , a currently accepted threshold for pulmonary valve replacement.
The medical records and results of cardiac magnetic resonance imaging and cardiopulmonary exercise testing of 25 consecutive eligible patients were reviewed. Twenty age- and gender-matched normal subjects were enrolled as cardiac magnetic resonance control. End-diastolic, end-systolic and stroke volumes, and ejection fraction (EF) were determined for the total RV and its components.
Of the 25 patients, 44% maintained normal exercise capacity. RV outlet EF was higher ( P = 0.02) and RV incisions smaller ( P = 0.04) in patients with normal exercise capacity than those with subnormal exercise capacity. Predicted peak oxygen consumption correlated better with the RV outflow tract EF than with the EF of other components of the RV or the global EF ( r = 0.59; P = 0.002). Multivariate analysis showed the RV outflow tract EF to be the only independent predictor of exercise capacity (ß = 0.442; P = 0.02).
Exercise capacity is preserved in some tetralogy of Fallot patients with severe RV dilatation. RV outflow tract EF is independently associated with exercise capacity in such patients, and could be a reliable determinant of intrinsic RV performance.
法洛四联症修复术后右心室严重扩张患者的运动能力与右心室各部分功能之间的关系尚不清楚。本研究旨在描述右心室舒张末期容积指数>150 ml/m²（目前公认的肺动脉瓣置换阈值）的法洛四联症修复术后患者的运动能力及其与右心室整体和各部分功能的关系。
回顾了25例连续符合条件患者的病历、心脏磁共振成像和心肺运动试验结果。纳入20名年龄和性别匹配的正常受试者作为心脏磁共振对照。测定右心室整体及其各部分的舒张末期、收缩末期和搏出量以及射血分数（EF）。
25例患者中，44%保持正常运动能力。运动能力正常的患者右心室流出道EF较高（P = 0.02），右心室切口较小（P = 0.04）。预测的峰值耗氧量与右心室流出道EF的相关性优于与右心室其他部分的EF或整体EF的相关性（r = 0.59；P = 0.002）。多变量分析显示右心室流出道EF是运动能力的唯一独立预测因素（β = 0.442；P = 0.02）。
一些右心室严重扩张的法洛四联症患者保留了运动能力。右心室流出道EF与此类患者的运动能力独立相关，可能是右心室固有功能的可靠决定因素。
