Division of Cardiology, Department of Pediatrics, The Children's Hospital of Philadelphia and the University of Pennsylvania Perelman School of Medicine, 34th and Civic Center Blvd, Philadelphia, PA 19104, USA.
Circ Cardiovasc Imaging. 2012 Sep 1;5(5):637-43. doi: 10.1161/CIRCIMAGING.112.972588. Epub 2012 Aug 6.
Patients with repaired tetralogy of Fallot are monitored for pulmonary regurgitation (PR) and right ventricular (RV) function. We sought to compare measures of PR and RV function on echocardiogram to those on cardiac magnetic resonance (CMR) and to develop a new tool for assessing PR by echocardiogram.
Patients with repaired tetralogy of Fallot (n=143; 12.5±3.2 years) had an echocardiogram and CMR within 3 months of each other. On echocardiogram, RV function was assessed by (1) Doppler tissue imaging of the RV free wall and (2) myocardial performance index. The ratio of diastolic and systolic time-velocity integrals measured by Doppler of the main pulmonary artery was calculated. CMR variables included RV ejection fraction, RV volumes, and pulmonary regurgitant fraction (RF). Pulmonary regurgitation was graded as mild (RF<20%), moderate (RF=20-40%), and severe (RF>40%). On CMR, RF was 34+17% and RV ejection fraction was 61+8%. Echocardiography had good sensitivity identifying cases with RF>20% (sensitivity 97%; 95% CI: 92-99%) but overestimated the amount of PR when RF<20% (false-positive rate 36%; 95% CI: 18-57%). The diastolic and systolic time-velocity integrals on echocardiogram showed moderate correlation with RF on CMR (R=0.60; P<0.0001). On CMR, RF of 20% and 40% corresponded with a diastolic and systolic time-velocity integral of 0.49 (95% CI: 0.44-0.56) and 0.72 (95% CI: 0.68-0.76), respectively. RV myocardial performance index correlated modestly with RV ejection fraction (r=-0.33; P<0.001).
This study suggests that the diastolic and systolic time-velocity integrals ratio may make a modest contribution to the overall assessment of PR in patients with repaired tetralogy of Fallot and warrants further investigation. However, echocardiography continues to have a limited ability to quantify PR and RV function as compared with CMR.
患有法洛四联症修复术的患者需要监测肺动脉瓣反流（PR）和右心室（RV）功能。我们旨在比较超声心动图和心脏磁共振（CMR）上的 PR 和 RV 功能测量，并开发一种新的超声心动图评估 PR 的工具。
143 例法洛四联症修复术患者（12.5±3.2 岁）在 3 个月内分别接受了超声心动图和 CMR。在超声心动图上，通过（1）RV 游离壁多普勒组织成像和（2）心肌做功指数评估 RV 功能。通过主肺动脉多普勒测量计算舒张和收缩时间-速度积分比。CMR 变量包括 RV 射血分数、RV 容积和 PR 分数（RF）。PR 分级为轻度（RF<20%）、中度（RF=20-40%）和重度（RF>40%）。CMR 上的 RF 为 34+17%，RV 射血分数为 61+8%。超声心动图在识别 RF>20%的病例时具有良好的敏感性（敏感性 97%；95%CI：92-99%），但在 RF<20%时高估了 PR 程度（假阳性率 36%；95%CI：18-57%）。超声心动图上的舒张和收缩时间-速度积分与 CMR 上的 RF 呈中度相关（R=0.60；P<0.0001）。在 CMR 上，RF 为 20%和 40%分别对应舒张和收缩时间-速度积分 0.49（95%CI：0.44-0.56）和 0.72（95%CI：0.68-0.76）。RV 心肌做功指数与 RV 射血分数中度相关（r=-0.33；P<0.001）。
本研究表明，舒张和收缩时间-速度积分比可能对法洛四联症修复术后患者 PR 的整体评估有一定的贡献，值得进一步研究。然而，与 CMR 相比，超声心动图在定量 PR 和 RV 功能方面仍然存在局限性。
