Background:Infective endocarditis (IE) in patients with adult congenital heart disease (ACHD) remains a diagnostic challenge due to difficulties in detecting endocardial lesions by echocardiography. ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) has shown good diagnostic performance in prosthetic valve IE. This study aimed to assess its additional diagnostic value in ACHD-associated IE and to characterize its advantages.

Methods and Results:Overall, 22 patients with ACHD and clinical suspicion of IE were retrospectively studied. ¹⁸F-FDG PET/CT was performed in addition to conventional assessment based on the modified Duke criteria. The final IE diagnosis was determined by an expert team during a 3-month clinical course, resulting in 18 patients diagnosed with IE. Seven patients (39%) were diagnosed with definite IE only by initial echocardiography. An ¹⁸F-FDG PET/CT assessment revealed endocardial involvement in the other 9 patients, resulting in the diagnosis of definite IE in 16 in total (88%). Right-sided endocardial lesions were more common (n=12, 67%) but rarely identified by echocardiography, whereas ¹⁸F-FDG PET/CT revealed right-sided lesions in 9 patients. A negative ¹⁸F-FDG PET/CT (n=7, 39%) assessment was associated with a native valve IE (71% vs. 0%). In 4 patients who were identified with not-IE, neither echocardiography nor ¹⁸F-FDG PET/CT detected any suspicious cardiac involvement.

Conclusions:In the diagnosis of ACHD-associated IE, characterized by right-sided IE, ¹⁸F-FDG PET/CT assessment should be useful.

背景：由于超声心动图难以检测心内膜病变，成人先天性心脏病 (ACHD) 患者的感染性心内膜炎 (IE) 仍然是一个诊断挑战。¹⁸ F-氟脱氧葡萄糖（ ¹⁸ F-FDG）正电子发射断层扫描/计算机断层扫描（PET/CT）在人工瓣膜IE中显示出良好的诊断性能。本研究旨在评估其在 ACHD 相关 IE 中的额外诊断价值并描述其优势。

方法和结果：总体而言，回顾性研究了 22 名临床怀疑为 IE 的 ACHD 患者。除了基于改良杜克标准的常规评估外，还进行了^{18 F-FDG PET/CT。}最终的 IE 诊断是由专家团队在 3 个月的临床过程中确定的，导致 18 名患者被诊断为 IE。7 名患者 (39%) 仅通过初始超声心动图诊断为明确的 IE。¹⁸ F-FDG PET/CT 评估显示其他 9 名患者的心内膜受累，总共有 16 名患者（88%）诊断为明确的 IE。右侧心内膜病变更常见（n=12, 67%），但超声心动图很少发现，而¹⁸F-FDG PET/CT 显示 9 例患者右侧病变。阴性¹⁸ F-FDG PET/CT (n=7, 39%) 评估与天然瓣膜 IE 相关（71% 对 0%）。在 4 名确诊为非 IE 的患者中，超声心动图和¹⁸ F-FDG PET/CT 均未检测到任何可疑的心脏受累。

结论：在以右侧 IE 为特征的 ACHD 相关 IE 的诊断中， ¹⁸ F-FDG PET/CT 评估应该是有用的。