Erbel R, Rohmann S, Drexler M, Mohr-Kahaly S, Gerharz C D, Iversen S, Oelert H, Meyer J
II. Medical Clinic, Johannes Gutenberg-University, Mainz, F.R.G.
Eur Heart J. 1988 Jan;9(1):43-53.
In a prospective study, the clinical value of transoesophageal two-dimensional echocardiography (TOE) as compared with transthoracic two-dimensional echocardiography (TTE) was determined in patients with suspected infective endocarditis. Ninety-six patients were studied consecutively with an electronic sector scanner using 2.25 and 3.5 MHz probes for TTE and a 3.5 MHz probe embedded in tip of a flexible 12 mm gastroscope for TOE. Results of surgery and autopsy were available for 20 of the 96 patients with infective endocarditis and echocardiographically demonstrated vegetations and 70 control patients with valvular heart disease without infective endocarditis and no signs of vegetations, who were studied preoperatively with TTE and TOE. For TTE and TOE, the measured sensitivity was 63% and 100%, specificity 98% and 98%, positive predictive accuracy 92% and 95%, and negative predictive accuracy 91% and 100%, respectively. In 39 patients who had positive blood cultures, vegetations were found by TOE in 32 patients (82%), but in only 27 patients (69%) by TTE. Image quality was the main factor contributing to the superiority of TOE over TTE: it was reduced in 11/20 patients (55%) in whom vegetations were not detected by TTE. Another important factor was the size of vegetations. Only 6/24 vegetations (25%) of less than 5 mm but 9/13 vegetations of 6-10 mm, and 14/14 vegetations of greater than 11 mm detected by TOE were also observed with TTE. The clinical importance of detecting vegetations was demonstrated by the rate of embolism. In patients with vegetations embolism was 25% when blood cultures were positive and 21% when they were negative. In patients without echocardiographically detectable vegetations signs of embolism were seen in no patient with positive and 7% of the patients with negative blood cultures. Evidence of vegetations was found on the aortic valve in 14 patients and on the mitral valve in seven patients in whom valvular incompetence was not present, indicating that the valve had not yet been damaged significantly. TOE is superior to TTE in detecting vegetations in suspected infective endocarditis because of better image quality, particularly when vegetations are small. TOE seems to be indicated in patients with suspected endocarditis and reduced image quality or negative TTE results. Early detection of vegetations on valves may help confirm the diagnosis of infective endocarditis at an early stage and hopefully lead to an improved prognosis by reducing delay in instituting appropriate therapy.
在一项前瞻性研究中，对疑似感染性心内膜炎患者，比较了经食管二维超声心动图（TOE）与经胸二维超声心动图（TTE）的临床价值。使用电子扇形扫描仪，分别用2.25和3.5MHz探头进行TTE检查，用嵌入12mm柔性胃镜尖端的3.5MHz探头进行TOE检查，对96例患者进行了连续研究。96例感染性心内膜炎患者中有20例以及70例瓣膜性心脏病对照患者（无感染性心内膜炎且无赘生物迹象）接受了手术和尸检，术前对这些患者进行了TTE和TOE检查。对于TTE和TOE，测得的敏感性分别为63%和100%，特异性分别为98%和98%，阳性预测准确率分别为92%和95%，阴性预测准确率分别为91%和100%。在39例血培养阳性的患者中，TOE在32例患者（82%）中发现了赘生物，而TTE仅在27例患者（69%）中发现了赘生物。图像质量是TOE优于TTE的主要因素：在TTE未检测到赘生物的20例患者中有11例（55%）图像质量下降。另一个重要因素是赘生物的大小。TOE检测到的小于5mm的赘生物中只有6/24（25%）也被TTE观察到，而6 - 10mm的赘生物中有9/13，大于11mm的赘生物中有14/14也被TTE观察到。赘生物检测的临床重要性通过栓塞发生率得以体现。有赘生物的患者中，血培养阳性时栓塞发生率为25%，血培养阴性时为21%。在无超声心动图可检测到赘生物的患者中，血培养阳性的患者无栓塞迹象，血培养阴性的患者中有7%出现栓塞迹象。在14例患者的主动脉瓣以及7例患者的二尖瓣上发现了赘生物，这些患者不存在瓣膜关闭不全，表明瓣膜尚未受到明显损害。在疑似感染性心内膜炎患者中，TOE在检测赘生物方面优于TTE，因为其图像质量更好，尤其是在赘生物较小时。对于疑似心内膜炎且图像质量下降或TTE结果为阴性的患者，似乎应选择TOE检查。早期检测瓣膜上的赘生物可能有助于早期确诊感染性心内膜炎，并有望通过减少开始适当治疗的延迟来改善预后。
