[Relationship of left ventricular wall motion to myocardial viability in patients with recent myocardial infarction].

The influence of left ventricular myocardial perfusion on left ventricular wall motion in patients with recent myocardial infarction was studied to try to differentiate viable myocardium from necrotic myocardium in 21 patients with initial myocardial infarction who received successful percutaneous transluminal coronary angioplasty (PTCA) 5-8 weeks after the onset. Exercise stress myocardial tomography with 201Tl (Ex-Tl) was performed before (3-5 weeks after acute onset) and after PTCA. Myocardial images were reconstructed into a bull's eye map which was divided into 17 segments. Rest ECG-gated cardiac blood pool tomography with 99mTc was performed before PTCA, and the left ventricular wall was divided into the same 17 segments used in Ex-Tl. The % shortening in each segment was calculated. Myocardial perfusion and % shortening were compared in each myocardial segment. Myocardial perfusion was classified into 4 types by considering whether exercise induced myocardial perfusion abnormality was transient (RD(+)) or persistent (RD(-)) in delayed image; 1) normal perfusion, 2) redistribution (+); RD(+): transient or viability exercise-induced perfusion defect before PTCA, 3) RD(-)/viable: fixed defect before PTCA but normal perfusion after PTCA, and 4) necrosis: fixed defect before and after PTCA. Most normal perfusion segments (88% of 184) showed normal wall motion and mean % shortening was 42 +/- 11%. Only 13 of 73 RD(+) segments showed normal wall motion. Thirty-eight and 19 RD(+) segments showed moderate hypokinesis and severe hypokinesis or akinesis, respectively. Mean % shortening in RD(+) segments was 19 +/- 13%. Thirty-seven of 38 RD(-)/viable segments had wall motion abnormalities, and 20 showed severe hypokinesis or akinesis. Mean % shortening in RD(-) segments was 12 +/- 8%. All 62 necrosis segments showed wall motion abnormalities including 10 with dyskinesis and 42 with akinesis or severe hypokinesis.(ABSTRACT TRUNCATED AT 250 WORDS)