Abstract 327: Reduced Myocardial Flow Reserve Quantified With Rubidium-82 PET is an Independent Predictor of Three Vessel Coronary Artery Disease
Objectives: Measurement of myocardial flow reserve (MFR) with Rb-82 PET may assist detection of 3-vessel disease (3-VD). Whether this method will be integrated into routine clinical practice remains to be elucidated. Our goal was to assess whether reduced MFR can predict significant (≥ 70%) 3-VD. We hypothesized that patients (pts) with 3VD compared to those without would have significantly reduced MFR.
Methods: We studied 706 pts who were referred for a Dipyridamole Rb-82 PET study for evaluation of ischemia (01/08–01/09); 193 had coronary angiogram within 6 months of the PET date. Pts with previous CABG and recent PCI were excluded, leaving 112 pts for the analysis.
Results: Pts with 3-VD (n=24) vs. those without were older, had more cardiovascular risk factors and significantly lower global MFR and stress flow (table⇓). Rest flow was similar in both groups. In the multivariable logistic model, MFR<2, hypertension and a positive family history were independent predictors of 3VD (all p<0.05). Figure 1⇓ shows an inverse relationship between MFR and the likelihood of 3VD (p<0.001).
Conclusions: Pts with 3-vessel CAD had more severely impaired global MFR and stress flow compared to those without. PET quantitative analysis may be useful to reveal the entire spectrum of disease, integrated with other imaging parameters. This warrants further investigation with a larger sample size.