Yue Li, Zhai Ya-nan, Wei Li-qun
Ultrasound Department of Chinese, PLA General Hospital, Beijing, China.
Echocardiography. 2014 Oct;31(9):1050-5. doi: 10.1111/echo.12523. Epub 2014 Feb 4.
At present there is no consensus on which technique is more suitable for the detection of right-to-left shunt (RLS) in patients with patent foramen ovale (PFO). The aim of study was to compare the efficacy of contrast transthoracic echocardiography (cTTE) and contrast transesophageal echocardiography (cTEE) in the detection of RLS.
A prospective study was undertaken in 29 patients with PFO. Both cTTE with harmonic imaging modality and cTEE with fundamental imaging modality were performed for all the patients. The severity of RLS were semiquantitatively assessed with a four-level grade system by scaling the numbers of microbubbles (MBs) in the left atrium after complete opacification of the right atrium within the first 3 cardiac cycles. Level 1 represents no MBs, indicating no RLS. Level 2, ≤10 MBs, indicating mild RLS. Level 3, 11-30 MBs, indicating moderate RLS and Level 4, >30 MBs, indicating severe RLS.
Contrast TTE demonstrated significantly higher sensitivity for detection of RLS than cTEE (86% vs. 56%, P < 0.05). For cTTE, there were 4, 1, 5, and 19 cases determined at levels 1, 2, 3, and 4, respectively, whereas for the same group of patients 13, 2, 6, and 7 cases were identified by cTEE at levels 1, 2, 3, and 4, respectively. The severity of RLS detected by cTTE was significantly greater than that by cTEE (P < 0.01).
Contrast TTE is more efficacious in the detection of RLS than cTEE. The former can be used as an alternative to the latter in clinical practice.
目前，对于哪种技术更适合检测卵圆孔未闭（PFO）患者的右向左分流（RLS）尚无共识。本研究的目的是比较对比剂经胸超声心动图（cTTE）和对比剂经食管超声心动图（cTEE）检测RLS的效果。
对29例PFO患者进行了一项前瞻性研究。所有患者均接受了采用谐波成像模式的cTTE和采用基本成像模式的cTEE检查。在最初3个心动周期内右心房完全显影后，通过对左心房内微气泡（MBs）数量进行四级分级系统半定量评估RLS的严重程度。1级表示无MBs，即无RLS。2级，≤10个MBs，提示轻度RLS。3级，11 - 30个MBs，提示中度RLS，4级，>30个MBs，提示重度RLS。
对比剂经胸超声心动图检测RLS的敏感性显著高于cTEE（86%对56%，P < 0.05）。对于cTTE，分别有4、1、5和19例患者被判定为1、2、3和4级，而对于同一组患者，cTEE分别在1、2、3和4级识别出13、2、6和7例。cTTE检测到的RLS严重程度显著高于cTEE（P < 0.01）。
对比剂经胸超声心动图在检测RLS方面比cTEE更有效。前者在临床实践中可作为后者的替代方法。
