1981 Volume 30 Issue 5 Pages 268-274
Five normal adults and 31 patients with ischemic heart disease were studied by stress test, and 201T1 was injected one min, before the end of the test. Myocardial scintigrams in three views were recorded at 10 min, 1 and 2 hours (phase 0, 1 and 2) after the injection. The myocardial wall was geometrically divided into 5 segments. At the area where the count rate (Cts) was highest in phase 0 scintigrams, the washout rate from phase i to j was defined as WRij= (maxCtsi-maxCtsj) /maxCtsi where Ctsi denoted Cts at phase i in the relevant area. The redistribution index (Rdsij) in each segment was defined as Rdsij= {Ctsi×WRij+ (Ctsi-Ctsj) } /Ctsi, where Ctsi denoted Cts at phase i in the segment. The ischemic segment was identified as 70% or less of maxCts 0, while the infarcted segment by VCG in phase 0 scintigram. Mean values of Rds 02 in the normal, ischemic and infarcted segments were -6.1±5.6, 9.7±7.0 and 3.5±7.2%, respectively, and the differences were statistically significant (p<0.001) . All the 26 patients with anginal except one showed WR 12/WR 01 greater than 1.0.When the peak pressurerate product that attained at the test was 200 or more, it was significantly correlated with WR 02 (r=0.80) .
The Redistribution index was helpful in quantitative assesment of the ischemic segments. The finding of WR 12>WR 01 after the stress was reliable in suggesting myocardial ischemia.
