[Myocardial viability in old myocardial infarction as evaluated by T1-201 SPECT and two-dimensional echocardiography]

Myocardial viability of the infarcted area was evaluated in 49 patients with old myocardial infarction by thallium-201 myocardial single photon emission computed tomography (SPECT), two-dimensional echocardiography (2 DE) and electrocardiography (ECG). The following results were obtained: 1. T1 uptake (%TU) correlated significantly with the % systolic thickening ratio (% delta Th) and the interventricular septal excursion (IVSE) (r = 0.66, r = 0.75), suggesting that both parameters are useful in predicting myocardial viability of the infarcted areas. 2. In 18 patients, the % delta Th was 0, IVSE ranged from -3 mm to +3 mm, and a positive correlation between %TU and IVSE was present, suggesting an advantage of IVSE over % delta Th as a parameter. 3. Forty-nine patients were categorized into 4 groups based on their ECG findings; 3 with QS and complete RBBB (Group A); 19 with QS and ST elevation (Group B); 10 with QS without ST elevation (Group C); and 17 with non-QS (Group D). All of %TU, % delta TH and IVSE increased in the order of Groups A < B < C < D. 4. The bull's eye method showed redistribution in 5 of 19 patients (26%) in Group B, 5 of 19 (26%) with % delta Th < or = 0 and 2 of 9 (22%) with IVSE < or = 0. These results suggested that transmural myocardial infarction, which has been considered irreversible, may be viable and PTCA or coronary bypass surgery is recommended if ECG or 2DE gives indications of myocardial viability.