Department of Pediatric Cardiology, Seattle Children's Hospital, University of Washington, 400 Sand Point Way NE, Seattle, WA, 98105, USA.
J Echocardiogr. 2022 Jun;20(2):106-114. doi: 10.1007/s12574-021-00558-1. Epub 2021 Nov 30.
In repaired tetralogy of Fallot (rTOF), right ventricular (RV) enlargement leads to poor outcomes. However, evaluating the RV has limitations; cardiac magnetic resonance (CMR) and 3D echocardiography have barriers including cost and accessibility. Traditional echocardiography is limited given the complex geometry and anterior location of the RV. We propose a novel echocardiographic evaluation of RV volume using 2 separate views.
This is a retrospective study of rTOF patients with echocardiogram, CMR, and exercise tests. By echocardiogram, we collected RV length in parasternal long axis (PLAX), area in 4-chamber (4C) view, and measurements per standard guidelines. RV end-diastolic and end-systolic volume (RVEDV and RVESV) were calculated as 5/9 (4C area * PLAX length).
Forty-five patients with 66 sets of CMR, echocardiogram, and exercise tests were included (mean age 13.3 ± 3.2 years). The echocardiographic RVEDV and RVESV showed strong correlation with CMR parameters (r = 0.81 and 0.72; p≤ 0.0001), and moderate correlation with peak oxygen pulse (0.63 and 0.49; p≤0.0001). Guideline measurements had no significant correlation. Echocardiographic RVEDV and RVESV were higher in those requiring subsequent pulmonary valve replacement. Indexed echocardiographic RVEDV of 93 ml/m had 92% sensitivity and 50% specificity (area under curve 0.75 (p = 0.001)) in predicting CMR RV/LV EDV ratio > 2, which is an early indicator for pulmonary valve replacement.
This novel technique correlates strongly with CMR, better than traditional parameters. While echocardiogram will not replace CMR, this method would be useful in predicting the RV volume, progression of dilation, and timing of CMR.
在修复性法洛四联症（rTOF）中，右心室（RV）扩大导致预后不良。然而，评估 RV 存在局限性；心脏磁共振（CMR）和 3D 超声心动图存在成本和可及性等障碍。鉴于 RV 的复杂几何形状和前位，传统超声心动图存在局限性。我们提出了一种使用 2 个独立视图评估 RV 容积的新超声心动图方法。
这是一项回顾性研究，纳入了接受超声心动图、CMR 和运动试验的 rTOF 患者。通过超声心动图，我们在胸骨旁长轴（PLAX）中收集 RV 长度，在 4 腔（4C）视图中收集 RV 面积，并按照标准指南进行测量。RV 舒张末期和收缩末期容积（RVEDV 和 RVESV）计算为 5/9（4C 面积 * PLAX 长度）。
共纳入 45 例患者的 66 组 CMR、超声心动图和运动试验数据（平均年龄 13.3±3.2 岁）。超声心动图 RVEDV 和 RVESV 与 CMR 参数具有很强的相关性（r=0.81 和 0.72；p≤0.0001），与峰值氧脉搏也具有中度相关性（0.63 和 0.49；p≤0.0001）。指南测量与两者均无显著相关性。需要后续行肺动脉瓣置换术的患者的超声心动图 RVEDV 和 RVESV 较高。超声心动图 RVEDV 指数为 93ml/m 时，预测 CMR RV/LV EDV 比值＞2 的敏感性为 92%，特异性为 50%（曲线下面积 0.75（p=0.001）），该比值是肺动脉瓣置换术的早期指标。
该新技术与 CMR 相关性很强，优于传统参数。虽然超声心动图不能替代 CMR，但该方法对于预测 RV 容积、扩张进展和 CMR 时机将非常有用。
