Endothelial dysfunction in systemic lupus erythematosus: evaluation with 13N-ammonia PET.

UNLABELLED Systemic lupus erythematosus (SLE) affects multiple organs and systems, severely involving the cardiovascular system. The aim of this study was to evaluate the presence of endothelial dysfunction with (13)N-ammonia PET in asymptomatic SLE patients. METHODS We enrolled 16 women with SLE and 16 healthy women. Myocardial blood flow (MBF) was quantified in a 64-slice PET/CT scanner at rest, during a cold pressor test (CPT), and during stress. Endothelium-dependent vasodilation index, %ΔMBF, and myocardial flow reserve (MFR) were calculated. RESULTS There were 16 women in the SLE group (mean age ± SD, 31.4 ± 8.3 y) and 16 women in the healthy control group (31.5 ± 11.1 y). Mean endothelium-dependent vasodilatation index and %ΔMBF were significantly lower in SLE patients (1.18 ± 0.55 vs. 1.63 ± 0.65, P = 0.04, and 18 ± 55 vs. 63 ± 65, P = 0.04, respectively). MFR was also lower in the SLE group (2.41 ± 0.59 vs. 2.73 ± 0.77, P = 0.20). CONCLUSION SLE patients who are free of active disease present abnormal coronary flow and endothelial dysfunction. It is necessary to develop and intensify treatment strategies directed to CAD in SLE patients.