FLUORODEOXYGLUCOSE UPTAKE IN DYSFUNCTIONAL MYOCARDIUM SUBTENDED BY ANOCCLUDED CORONARY-ARTERY - RELATION TO DOBUTAMINE CONTRACTILE RESERVEAND SESTAMIBI UPTAKE

Background. Myocardial segments with impaired function may have the po tential for functional recovery. Augmented exogenous glucose uptake in relation to blood flow estimated by [2-18F]2-fluorodeoxyglucose (FDG) and positron emission tomography (PET) frequently indicates functiona l reversibility. The spectrum of EDG uptake levels in relation to Sest amibi uptake and dobutamine contraction reserve in areas with impaired function subtended by an occluded coronary artery has never been repo rted. Methods and results. Seventeen patients with stable angina pecto ris and dysfunctional myocardium subtended by an occluded coronary art ery were studied with FDG-PET, low-dose dobutamine echocardiography an d Sestamibi - Single Photon Emission Computerized Tomography. In a 16 segment model dysfunctional myocardial segments showed a normally dist ributed FDG uptake ranging from 34% to 150% when normalized to peak se gmental Sestamibi uptake. Low FDG uptake was associated with both lack of dobutamine induced contractile reserve and low Sestamibi uptake (i n 73% of the segments) whereas high FDG uptake displayed both contract ile reserve and Sestamibi uptake (57%). Segments with intermediate FDG uptake had either contractile reserve or a preserved Sestamibi uptake (62%). Conclusion. Dysfunctional myocardium subtended by an occluded coronary artery represents a continuum of metabolic states with a high degree of heterogeneity with regard to contractile reserve and Sestam ibi uptake.