PREDICTIVE VALUE OF REST-REDISTRIBUTION TC-99M-TETROFOSMIN SPECT IN THE DETECTION OF RESIDUAL VIABILITY IN THE TERRITORY OF INFARCT-RELATEDARTERY IN THE LATE-PHASE OF MI (VOL 29, PG 7644, 1997)

The aim of the study was to determine the value of rest-redistribution (RR) Tc-99m-tetrofosmin SPECT in the detection of residual myocardial viability in the late phase of MI. Twenty nine asymptomatic consecuti ve patients (pts) (age 58.5+/-11.9 years) were prospectively studied b y RR protocol in the week before planned PTCA of infarct related arter y (IRA). Each pt had a contrast ventriculo-coronarography at inclusion (15+/-7.5 days after MI) and 67+/-8.4 days after successful PTCA. Reg ional wall motion abnormalities (RWMA) were quantitatively assessed by center line method and expressed in SD. SPECT data were analysed quan titatively (18 sectors/pt). The values of each sector were normalized to a normal data base, expressed in SD and averaged for the IRA territ ory (TR). Nineteen pts completed the overall protocol. The RWMA improv ed in 12 pts (63%) after PTCA. The mean uptake at rest was not differe nt between the viable and non viable TRs (-4.2+/-2.2 vs -6.7+/-4.4, p= NS). In contrast the viable and non viable TRs were well separated at redistribution (-5.7+/-2.5 vs -10.1+/-4.2, p<0.05), and even better if only the best 50% of sectors in the IRA TRs were taken into account ( -3.6+/-3.7 vs -5.8+/-2.5, p<0.01). With a cutoff point of -4.0 SD, the sensitivity, specificity, PPV and NPV were then 81.8%, 83.3%, 90.0% a nd 71.4%, respectively. In conclusion, the uptake of Tc-99m-tetrofosmi n in the peri-infarction area at redistribution predicts the residual viability in the TR of IRA.