Department of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada.
Department of Cardiology, Michael Garron Hospital, Toronto, Ontario, Canada.
J Am Soc Echocardiogr. 2019 Dec;32(12):1551-1557.e1. doi: 10.1016/j.echo.2019.08.018. Epub 2019 Oct 31.
Transesophageal echocardiography (TEE) remains the preferred test to rule out infective endocarditis (IE) but is resource intensive and carries risk. Multiple studies report low sensitivity of transthoracic echocardiography (TTE) for detection of IE; however, these studies did not account for TTE quality. We test the validity of a simple valve visualization grading tool to stratify TTEs by quality and determine whether a high-quality TTE may be used to exclude valvular vegetation and forgo the need for TEE.
The Valve Visualization on Echocardiography Grade (VEG) tool scores the TTE from 0 to 10 based on leaflet visualization and valve leaflet clarity. The tool was retrospectively applied to 309 sequential patients who underwent both TTE and TEE at an academic teaching hospital between 2011 and 2015. The TEE report was the gold standard for presence or absence of vegetation. Patients with prosthetic valves and pacemaker wires were excluded. Sensitivity of TTE for detecting vegetation was calculated at each VEG score, and the optimal cutoff was identified.
A total of 309 patients were included in the analysis. Among the 216 negative TTEs, 19 (9%) had a positive TEE. The median VEG score was 4. A VEG score cutoff >6 provided optimal sensitivity and was used as the cutoff. Overall, 75 (25%) patients had a VEG score >6, and 234 (75%) had a score ≤6. Sensitivity and negative predictive value for IE were higher in the VEG >6 versus VEG ≤6 group (sensitivity 96% vs 66%, negative predictive value 97.5% vs 90%; P < .05). The false-negative rate was lower (2.5% vs 10%; P = .04) in VEG > 6 versus VEG ≤ 6 groups, respectively.
Leaflet visualization and valve leaflet clarity are important components in the TTE evaluation of patients with suspected IE. This study demonstrates that the better the valve leaflets are visualized on TTE (as represented in this population by a score >6), the higher the confidence one can have that the TTE will not be falsely negative for vegetation(s) when vegetation(s) are not noted on these TTEs. If validated in future prospective studies, this may reduce the need to perform an invasive TEE in selected patients undergoing evaluation for native valve IE.
经胸超声心动图（TTE）仍然是排除感染性心内膜炎（IE）的首选检查方法，但资源密集且存在风险。多项研究报告 TTE 检测 IE 的敏感性较低；然而，这些研究并未考虑 TTE 质量。我们测试了一种简单的瓣膜可视化分级工具的有效性，该工具可根据质量对 TTE 进行分层，并确定高质量的 TTE 是否可用于排除瓣膜赘生物并避免 TEE 的需要。
瓣膜超声心动图分级（VEG）工具根据瓣叶可视化和瓣叶清晰度对 TTE 进行 0 到 10 的评分。该工具在 2011 年至 2015 年间在一家学术教学医院对 309 例连续接受 TTE 和 TEE 的患者进行了回顾性应用。TEE 报告是有无赘生物的金标准。排除了人工瓣膜和起搏器导线的患者。计算了每个 VEG 评分的 TTE 检测赘生物的敏感性，并确定了最佳截止值。
共纳入 309 例患者进行分析。在 216 例 TTE 阴性的患者中，有 19 例（9%） TEE 阳性。中位数 VEG 评分为 4。VEG 评分>6 为最佳截断值。总体而言，75 例（25%）患者 VEG 评分>6，234 例（75%）患者 VEG 评分≤6。VEG>6 与 VEG≤6 组 IE 的敏感性和阴性预测值更高（敏感性 96%比 66%，阴性预测值 97.5%比 90%；P<0.05）。VEG>6 与 VEG≤6 组的假阴性率较低（2.5%比 10%；P=0.04）。
瓣叶可视化和瓣叶清晰度是 TTE 评估疑似 IE 患者的重要组成部分。本研究表明，在 TTE 上更好地可视化瓣叶（在该人群中代表为评分>6），当 TTE 上未发现赘生物时，对 TTE 不会因赘生物而出现假阴性的信心就越高。如果在未来的前瞻性研究中得到验证，这可能会减少在评估原生瓣膜 IE 时对某些患者进行有创 TEE 的需要。
