Maffè Stefano, Dellavesa Pierfranco, Zenone Franco, Paino Anna Maria, Paffoni Paola, Perucca Antonello, Kozel Daniela, Signorotti Fabiana, Bielli Massimo, Parravicini Umberto, Pardo Nicolò Franchetti, Cucchi Lorenzo, Aymele Alain Guillaime, Zanetta Marco
Division of Cardiology, SS Trinità Borgomanero Hospital, ASL No-Novara, Italy.
Eur J Echocardiogr. 2010 Jan;11(1):57-63. doi: 10.1093/ejechocard/jep165. Epub 2009 Nov 12.
Transoesophageal echocardiography (TEE) with contrast administration is still considered as the reference method for the detection of patent foramen ovale (PFO) with interatrial shunt, but it is a semi-invasive exam. The aim of the present study is to evaluate a role of two- and three-dimensional transthoracic echocardiography (TTE and R3DTE) as a diagnostic alternative to transcranial Doppler ultrasound (TCD) and TEE for detection of atrial right-to-left shunt.
Seventy-five patients with history of cerebrovascular events were subjected to four diagnostic examinations: TCD, TTE, R3DTE, and TEE, with bubble contrast. Bubbles in the left atrium within three cardiac cycles were considered diagnostic for PFO and later as a pulmonary shunt. Greater than 20 bubbles in the left atrium were considered a large shunt and <20 a small shunt. Every exam was read blinded to the results of the others. From the 75 enrolled patients, 62 (82.6%) patients showed right-to-left shunt with TEE; the results were also positive in 53 patients using TCD (70.6%), in 53 using R3DTE (70.6%), and in 55 using TTE (73.3%) (P = NS). There is a statistically significant superiority for TEE in the capacity of detecting shunts compared with TCD (P < 0.024), TTE (P < 0.018), and R3DTE (P < 0.018). The TEE presents a superior ability to recognize mild/moderate interatrial shunts respect to other exams (P = 0.003), without differences for shunts of high degree. In comparison to the TEE, the sensitivity is 89% for TTE, 88% for R3DTE, and 85% for TCD; the specificity is 100% for TTE and R3DTE, and 90% for TCD; the positive predictive value is 100% for TTE and R3DTE, and 98% for TCD; and the negative predictive value is 65% for TTE, 65% for R3DTE, and 53% for TCD. Considering only for mild/moderate shunts, the diagnostic accuracy is clearly inferior (sensitivity 63% for TTE, 58% for R3DTE, and 53% for TCD).
In this cohort of patients, TEE confirms the role of 'gold standard' exam for the detection of PFO; the non-invasive methods, and the TTE in particular, present a good diagnostic accuracy, but are inferior to the TEE because of the low negative predictive value and the non-optimal detection of small shunts. If the only purpose of TEE is the detection of significative interatrial shunt, TEE can be replaced by TTE. The R3DTE presents a good diagnostic accuracy, provides a better anatomical definition of the interatrial septum, and may have a role in this setting of patients, but does not add a lot to the TTE for the diagnosis.
经食管超声心动图（TEE）结合造影剂注射仍被视为检测存在房间隔分流的卵圆孔未闭（PFO）的参考方法，但它是一种半侵入性检查。本研究的目的是评估二维和三维经胸超声心动图（TTE和R3DTE）作为经颅多普勒超声（TCD）和TEE检测心房右向左分流的诊断替代方法的作用。
75例有脑血管事件病史的患者接受了四项诊断检查：TCD、TTE、R3DTE和TEE（使用气泡造影剂）。三个心动周期内左心房出现气泡被视为PFO的诊断依据，随后视为肺分流。左心房内大于20个气泡被视为大分流，小于20个为小分流。每项检查的结果均在对其他检查结果不知情的情况下进行判读。在75例入组患者中，62例（82.6%）经TEE检查显示右向左分流；使用TCD检查的53例患者（70.6%）、使用R3DTE检查的53例患者（70.6%）以及使用TTE检查的55例患者（73.3%）结果也为阳性（P=无显著性差异）。与TCD（P<0.024）、TTE（P<0.018）和R3DTE（P<0.018）相比，TEE在检测分流方面具有统计学上的显著优势。与其他检查相比，TEE识别轻度/中度房间隔分流的能力更强（P=0.003），对于高度分流则无差异。与TEE相比，TTE的敏感性为89%，R3DTE为88%，TCD为85%；TTE和R3DTE的特异性为100%，TCD为90%；TTE和R3DTE的阳性预测值为100%，TCD为98%；TTE的阴性预测值为65%，R3DTE为65%，TCD为53%。仅考虑轻度/中度分流时，诊断准确性明显较低（TTE的敏感性为63%，R3DTE为58%，TCD为53%）。
在该队列患者中，TEE证实了其作为检测PFO的“金标准”检查的作用；非侵入性方法，尤其是TTE，具有良好的诊断准确性，但由于阴性预测值较低且对小分流检测不理想，低于TEE。如果TEE的唯一目的是检测有意义的房间隔分流，TEE可被TTE替代。R3DTE具有良好的诊断准确性，能更好地显示房间隔的解剖结构，在这类患者中可能有一定作用，但在诊断方面相比TTE并无太多优势。
