Osborne Michael T, Hulten Edward A, Singh Avinainder, Waller Alfonso H, Bittencourt Marcio S, Stewart Garrick C, Hainer Jon, Murthy Venkatesh L, Skali Hicham, Dorbala Sharmila, Di Carli Marcelo F, Blankstein Ron
Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
J Nucl Cardiol. 2014 Feb;21(1):166-74. doi: 10.1007/s12350-013-9828-6. Epub 2013 Dec 3.
Cardiac positron emission tomography (PET) using (18)F-fluorodeoxyglucose (FDG) has been used to diagnose and monitor cardiac sarcoidosis (CS). It is not known whether a reduction in myocardial inflammation, as measured by FDG uptake, is associated with improvement in LV ejection fraction (EF).
For 23 patients with CS followed by a total of 90 serial PET exams (median 4 per patient), two physicians blinded to EF quantified the maximum of standardized uptake value (SUV) and volume of inflamed tissue above two distinct thresholds to assess the intensity and extent of FDG uptake on each study. Using gated (82)Rubidium rest myocardial perfusion images, EF was measured blinded to all clinical and FDG data. To account for clustering and differences in scan frequency, a longitudinal mixed effects model was used to evaluate the relationship between FDG uptake and changes in EF on interval scans.
Among 23 patients with serial PET exams (mean age 49, 74% male, mean baseline EF 43% ± 13%), the median time between the first and last scan was 2.0 years. Overall, 91% were treated with corticosteroids, 78% with ACE/ARB, 83% with beta-blockers, and 83% had ICDs. Longitudinal regression demonstrated a significant inverse linear relationship between maximum SUV and EF with an expected increase in EF of 7.9% per SUV reduction of 10 g·mL(-1) (P = .008). Likewise, in an analysis based on volume, there was an increase in EF of 2.1% per 100 cm(3) decrease in volume of inflamed tissue using a threshold of 2.7 g·mL(-1) (P = .028) and an increase in EF of 3.8% per 100 cm(3) decrease (P = .022) using a SUV threshold of 4.1 g·mL(-1).
In a longitudinal cohort of CS patients, a reduction in the intensity and extent of myocardial inflammation on FDG PET is associated with improvement in EF. These data suggest serial PET scanning may help guide titration of immunosuppressive therapy to improve or prevent heart failure in CS.
使用（18）F-氟脱氧葡萄糖（FDG）的心脏正电子发射断层扫描（PET）已被用于诊断和监测心脏结节病（CS）。尚不清楚通过FDG摄取测量的心肌炎症减轻是否与左心室射血分数（EF）的改善相关。
对23例CS患者进行了总共90次连续PET检查（每位患者中位数为4次），两名对EF不知情的医生对标准化摄取值（SUV）的最大值和高于两个不同阈值的炎症组织体积进行了量化，以评估每次研究中FDG摄取的强度和范围。使用门控（82）铷静息心肌灌注图像，在对所有临床和FDG数据不知情的情况下测量EF。为了考虑扫描频率的聚类和差异，使用纵向混合效应模型来评估FDG摄取与间隔扫描时EF变化之间的关系。
在23例接受连续PET检查的患者中（平均年龄49岁，74%为男性，平均基线EF为43%±13%），首次扫描与末次扫描之间的中位时间为2.0年。总体而言，91%的患者接受了皮质类固醇治疗，78%接受了ACE/ARB治疗，83%接受了β受体阻滞剂治疗，83%植入了ICD。纵向回归显示，最大SUV与EF之间存在显著的负线性关系，每降低10 g·mL（-1）的SUV，EF预期增加7.9%（P = 0.008）。同样，在基于体积的分析中，使用2.7 g·mL（-1）的阈值时，炎症组织体积每减少100 cm（3），EF增加2.1%（P = 0.028）；使用4.1 g·mL（-1）的SUV阈值时，每减少100 cm（3），EF增加3.8%（P = 0.022）。
在一组CS患者的纵向队列中，FDG PET上心肌炎症强度和范围的降低与EF的改善相关。这些数据表明，连续PET扫描可能有助于指导免疫抑制治疗的滴定，以改善或预防CS患者的心力衰竭。
