VALUE OF METABOLIC IMAGING WITH POSITRON EMISSION TOMOGRAPHY FOR EVALUATING PROGNOSIS IN PATIENTS WITH CORONARY-ARTERY DISEASE AND LEFT-VENTRICULAR DYSFUNCTION

Patients with coronary artery disease (CAD) and severe left ventricula r (LV) dysfunction have a high but variable annual mortality and some may benefit from myocardial revascularization. This study aimed to eva luate the prognostic value of positron emission tomography (PET), and its interrelation with the choice of medical therapy or revascularizat ion for predicting survival and improvement in symptoms of heart failu re in patients with CAD and LV dysfunction. Ninety-three consecutive p atients with angiographic CAD and a mean LV ejection fraction of 0.25 who underwent cardiac PET studies for assessment of hypoperfused yet v iable myocardium (''mismatch pattern'') using N-13 ammonia and 18-F de oxyglucose were followed up for an average of 13.6 months. Fifty patie nts underwent medical treatment and 43 underwent revascularization. Th e Cox model analysis showed that the extent of mismatch had a negative effect (p = 0.02), whereas revascularization had a positive effect on survival (p = 0.04). The annual survival probability of patients with mismatch receiving medical therapy was lower than of those without mi smatch (50 vs 92%, p = 0.007). Patients with mismatch who underwent re vascularization had a higher survival rate than those treated medicall y (88 vs 50%, p = 0.03). The presence of mismatch also predicted impro vement in heart failure symptoms after revascularization (p <0.001). T hese results suggest that the presence of mismatch in patients with CA D and severe LV dysfunction is associated with poor annual survival wi th medical therapy. Revascularization in patients with PET mismatch ap pears to be associated with improved survival and heart failure sympto ms.