| J Nucl Med 1995 Sep;36(9):1543-1552 |
Delineation of myocardial viability with PET.
Grandin C, Wijns W, Melin JA, Bol A, Robert AR, Heyndrickx GR, Michel C, Vanoverschelde
JL.
Relative flow and metabolic imaging (the "mismatch pattern") with PET have been
proposed to identify the presence of viable myocardium in patients with ischemic left
ventricular dysfunction. Yet, optimal criteria to identify dysfunctional but viable
myocardium and predict significant functional improvement have not been fully defined.
METHODS: Dynamic PET imaging with 13N-ammonia and 18F-deoxyglucose to assess absolute
myocardial perfusion and glucose uptake was performed in 25 patients (20 men, 5 women;
mean age 57 +/- 12 yr, range 30-72 yr) scheduled for coronary revascularization because of
coronary artery disease, anterior wall dysfunction and mildly depressed left ventricular
ejection fraction (49% +/- 11%). Global and regional left ventricular function was
evaluated by contrast left ventriculography at baseline and after revascularization.
RESULTS: As judged from the changes in end-systolic volume and resting anterior wall
motion before and after revascularization, 17 patients with improved wall motion score and
decreased end-systolic volume were considered to have viable myocardium, whereas 8
patients with either no change in regional wall motion or increased end-systolic volume
were considered to have nonviable myocardium. Before revascularization, viable myocardium
showed higher absolute myocardial blood flow (77 +/- 20 versus 51 +/- 9 ml (min.100 g)-1,
p = 0.004) and absolute regional myocardial glucose uptake (36 +/- 14 versus 24 +/- 11
mumole (min.100 g)-1, p = 0.04) than nonviable myocardium. CONCLUSION: This study
identified absolute myocardial blood flow and normalized glucose extraction as the most
powerful predictors of the return of contractile function after coronary revascularization
in patients with ischemic anterior wall dysfunction.
