Abstract 16597: FDG-PET-CT Measurement of Arterial Inflammation Provides Insight into Both Risk for and Timing of Future Cardiovascular Events

Abstract

Background: It has previously been demonstrated that arterial FDG Uptake is associated with cardiovascular events. Here, we test the hypothesis that baseline arterial inflammation is higher in individuals with subsequent near-term (vs. far-term) cardiovascular events.

Methods: We serially identified patients (n=513, median age[IQR], 55[45,66], 42% males) who had undergone FDG-PET imaging for clinical indications but who were found to be free of active cancer, prior history of CVD, or acute or chronic inflammatory conditions and for whom clinical follow-up information was available, (median:49 months, range: 0-79 months). Major cardiovascular events (MACE, n=44) were adjudicated (defined as incident stroke, transient ischemic attack, acute coronary syndrome, revascularization, new-onset angina-with evidence of clinical atherosclerosis, peripheral arterial disease, or CVD death). Arterial inflammation was measured as target-to-background ratio (TBR) of ascending aortic FDG uptake on PET-CT images while blinded to clinical data. The association between TBR and the timing of MACE was assessed.

Results: Arterial inflammation (TBR) was inversely related to the time interval between imaging and subsequent MACE; (TBR±sd: 2.27±0.34, 2.16±0.29, 2.12±0.23, and 1.98±0.28 respectively for patients experiencing events at 0-6 months, 7-24 months, >24-79 months, and no events in 79 months respectively, p=0.001). Further, individuals with a TBR of ≥ 2.27 had an increased risk, OR[95% CI]: 5.4[2.43, 11.95], p=0.0001 for MACE within 6 months vs. individuals with a TBR ≤1.98. Adjusting for Framingham risk scores, those with higher TBR remained at an increased risk for MACE within 6 months, 7[2.3, 21],p=0.0006.

Conclusions: Measurement of arterial inflammation (by FDG PET-CT) provides an index of risk of future cardiovascular event and may also provide information about the timing of the event. These findings should be prospectively validated in a larger cohort.