TECHNETIUM-99M-SESTAMIBI IMAGING WITH NITRATE INFUSION TO DETECT VIABLE HIBERNATING MYOCARDIUM AND PREDICT POSTREVASCULARIZATION RECOVERY

We tested the relationship of nitrate-induced changes in (TC)-T-99m-se stamibi perfusion tomography and first-pass radionuclide angiocardiogr aphy (FPRNA) with postrevascularization functional recovery of asynerg ic territories. Methods: Twenty-eight patients, all with prior infarct ion and left ventricular dysfunction, underwent two Tc-99m-sestamibi r est studies: one under baseline conditions and the other with nitrate infusion. The baseline study was repeated after revascularization. Cha nges in global and regional perfusion and ventricular function were ev aluated by perfusion tomography and FPRNA. Hibernating myocardium was identified by functional recovery in postrevascularization FPRNA. Resu lts: Eleven patients and 31 segments in 19 coronary territories had fu nctional recovery. Nitrate-induced FPRNA changes showed poor agreement with postrevascularization modifications: kappa = 0.24, ns, for the g lobal and kappa = 0.32, p < 0.01 for regional function. The agreement between nitrate-induced and postrevascularization perfusion changes wa s good both considering the patients (k = 0.57, p < 0.01) and the abno rmal coronary territories (k = 0.63, p < 0.0005). The agreement of nit rate-induced perfusion changes with postrevascularization functional o utcome was excellent on a patient (k = 1, p < 0.0005), and coronary te rritory basis (k = 0.82, p < 0.0005). Conversely, the agreement betwee n nitrate and postrevascularization FPRNA was poor: k = 0.18, ns. Conc lusion: These data suggest that the nitrate-induced changes in Tc-99m- sestamibi perfusion imaging are useful to detect hibernating myocardiu m which recovers its function after revascularization.