Comparison of carbon-11-acetate with fluorine-18-fluorodeoxyglucose for delineating viable myocardium by positron emission tomography

Objectives. This study was designed to determine in patients with advanced coronary disease whether prediction of recovery of mechanical function after coronary revascularization could be accomplished more effectively by positron emission tomography (PET) with Carbon-11 (¹¹C)-acetate than by PET with fluorine-18 (¹⁸F)-fluorodeoxyglucose. Background.Results of previous studies have demonstrated that preservation of myocardial oxidative metabolism (measured by PET with ¹¹C-acetate) is necessary for recovery of systolic function after coronary revascularization. Methods. Myocardial oxidative metabolism was quantified before revascularization in 34 patients by the analysis of the rate of myocardial clearance of ¹¹C-acetate. Metabolism of glucose was assessed by analysis of uptake of ¹⁸F-fluorodeoxyglucose. Receiver operating characteristic curves for predicting functional recovery were derived for the measurements of oxidative metabolism and glucose metabolism. In addition, criteria for prediction of recovery of function based on measurements of oxidative metabolism and glucose metabolism were developed and compared. Results. Analysis of receiver operating characteristic curves indicated that estimates of oxidative metabolism were more robust in predicting functional recovery than were estimates of glucose metabolism (p < 0.02). Moreover, thershold criteria with ¹¹C-acetate exhibited superior positive and negative predictive values (67% and 89%, respectively) than did the criteria with ¹⁸F-fluorodeoxyglucose (52% and 81%, respectively), p < 0.01. In segments with initially severe dysfunction, estimates of oxidative metabolism tended to be more robust than estimates of glucose metabolism in predicting functional recovery. Moreover, in such segments, the threshold criteria with ¹¹C-acetate to exhibit superior positive and negative predictive values (85% and 87%, respectively) than did the criteria with ¹⁸F-fluorodeoxyglucose (72% and 82%, respectively), although statistical significance was not achieved. Conclusions. In patients with advanced coronary artery disease, the extent to which functional recovery can be anticipated after coronary revascularization can be delineated accurately by quantification of regional oxidative metabolism by PET with ¹¹C-acetate.