University College London Institute for Cardiovascular Science and Barts Heart Centre, St. Bartholomew's Hospital, West Smithfield, EC1A 7BE, London, UK.
Institute of Nuclear Medicine, University College London Hospitals, UK.
Eur Heart J Cardiovasc Imaging. 2018 Jul 1;19(7):757-767. doi: 10.1093/ehjci/jex340.
Cardiac death is the leading cause of mortality in patients with sarcoidosis, yet cardiac involvement often remains undetected. Cardiovascular magnetic resonance imaging (CMR) and 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) have been used to diagnose cardiac sarcoidosis (CS) yet never simultaneously in a cohort. This study sought to assess the diagnostic and prognostic utility of simultaneous hybrid cardiac PET/MR.
Fifty-one consecutive patients with suspected CS (age 50 ± 13 years, 31 males) underwent simultaneous PET/MR following a high-fat/low-carbohydrate diet and 12-h fast. Blinded image analysis of FDG uptake and late gadolinium enhancement (LGE) was performed using the American Heart Association (AHA) 16-segment model. The sensitivity and specificity of PET/MR for diagnosing CS was estimated using the Japanese Ministry of Health and Welfare guidelines. The primary endpoint was a composite of death, aborted sudden cardiac death, sustained ventricular arrhythmia, complete heart block, and hospital admission with decompensated heart failure. The secondary endpoints were a fall in left ventricular ejection fraction (LVEF) >10%, non-sustained ventricular tachycardia and other cardiac-related hospital admission. The prevalence of CS was 65% (n = 33). The sensitivity of PET and CMR alone for detecting CS was 0.85 and 0.82, respectively. Hybrid PET/MR was superior for detecting CS with sensitivity, specificity, positive, and negative predictive values of 0.94, 0.44, 0.76, and 0.80, respectively. There was poor inter-modality agreement for the location of cardiac abnormalities (k = 0.02). Over the median follow-up of 2.2 years, there were 18 (35%) adverse events. Cardiac RV PET abnormalities and presence of LGE were independent predictors of adverse events. Abnormalities found on both PET and magnetic resonance imaging was the strongest predictor of major adverse cardiac events.
Simultaneous PET/MR is an accurate method for diagnosing CS. FDG-PET and CMR combined offers complementary information on disease pathophysiology. The presence of LGE and FDG uptake on PET/MR identifies patients at higher risk of adverse events. PET and CMR should therefore be considered in the assessment of disease presence, stage, and prognosis in CS.
心脏性死亡是肉样瘤病患者死亡的主要原因，但心脏受累通常未被发现。心血管磁共振成像（CMR）和 18F-氟脱氧葡萄糖（FDG）-正电子发射断层扫描（PET）已被用于诊断心脏肉样瘤病（CS），但从未同时在一个队列中使用。本研究旨在评估同时进行的心脏 PET/MR 的诊断和预后效用。
51 例疑似 CS（年龄 50±13 岁，31 名男性）在进行高脂肪/低碳水化合物饮食和 12 小时禁食后接受了同时进行的 PET/MR。使用美国心脏协会（AHA）16 节段模型进行 FDG 摄取和晚期钆增强（LGE）的盲法图像分析。使用日本厚生劳动省指南估计 PET/MR 诊断 CS 的敏感性和特异性。主要终点是死亡、心脏骤停猝死、持续性室性心律失常、完全性心脏阻滞和因心力衰竭失代偿而入院的复合终点。次要终点是左心室射血分数（LVEF）下降>10%、非持续性室性心动过速和其他与心脏相关的住院治疗。CS 的患病率为 65%（n=33）。PET 和 CMR 单独检测 CS 的敏感性分别为 0.85 和 0.82。混合 PET/MR 对 CS 的检测更具优势，其敏感性、特异性、阳性预测值和阴性预测值分别为 0.94、0.44、0.76 和 0.80。心脏异常的位置的两种模式之间的一致性较差（k=0.02）。在中位数为 2.2 年的随访期间，有 18 例（35%）发生不良事件。RV 心脏 PET 异常和 LGE 存在是不良事件的独立预测因素。PET 和磁共振成像上均存在异常是主要不良心脏事件的最强预测因素。
同时进行的 PET/MR 是诊断 CS 的准确方法。FDG-PET 和 CMR 联合提供了疾病病理生理学的互补信息。PET/MR 上的 LGE 和 FDG 摄取可识别出发生不良事件风险较高的患者。因此，在 CS 的疾病存在、分期和预后评估中，应考虑使用 PET 和 CMR。
