Evaluating The Cardiac Function In Different Imaging Phases Post Exercise And Rest By Gated SPECT Myocardial Perfusion Imaging

Objectives:The aim was to evaluate cardiac function in different imaging phases post exercise by gated myocardial perfusion SPECTMethods:Forty-seven consecutive subjects were studied by conventional diagnostic 2 day stress/rest gated SPECT following injection 99mTc-MIBI using a dual-headed SPECT camera. Sequential imaging was started 15,35 and 120 minutes after exercise.33 volunteers in normal group(Ⅰ),13 patients(pts.)in risk factor of CAD group(Ⅱ)and one myocardial infarction patient. EF and LV volumes(end-diastolic volume(EDV)and end-systolic volume(ESV))were calculated using an automatic algorithm(QGS),while the EDV diversity was calculated(stress EDV-rest EDV)/rest EF.The ESV diversity is the same too.Results:①Perfusion imaging and LV function of 46 groupⅠand groupⅡwere all normal.②Chang of EF and LV volumesGroupⅠ:The EF values of post exercise at 35m was highest,There has significant differences only between post exercise 35m and rest(p＜0.05),EDV at 15m post exercise is lower than at rest.ESV values did not have statistically significant at post exercise 15,35,120m and rest.The heart rate at post exercise 15,35m was higher significant than rest(90.03±9.26, 81.33±9.05,73.67±11.27,p＜0.05).GroupⅡ:There weren't statistically significant in EF,EDV,ESV and△EF,The heart rate at post exercise 15,35m was higher significant than rest(85.23±11.03,73.31±11.57,p＜0.05).The EF and△EF of the same gender subjects in groupⅠandⅡdid not have statistically significant.But groupⅠhad a higher△EF than groupⅡ.③Diversity of EDV and ESVDiversity of EDV:In GroupⅠ,54.55%and 24.24%subjects were descent at 15m and 35m respectively,all subjects were normal at 2h,No one was ascend.In GroupⅡ.,only 30.77% subjects were descent at 15m,7.69%subjects didn't recovery at 2h,but 7.69%,15.38%and 23.08%subjects were ascend at 15m,35m and 2h respectively.Diversity of ESV:In GroupⅠ,72.72%and 66.67%volunteers were descent at 15m and 35m respectively,No one was ascending.In GroupⅡ.,69.23%and 23.08%were descent at 15m and 35m respectively,23.08%and 30.77%were ascend at 15m and 35m respectively. Conclusions:Different imaging phases was affect to cardiac function post exercise by gated myocardial perfusion SPECT in volunteers and patients with CAD risk factor:①EF were all ascend at early imaging phases(15m and 35m).In GroupⅠ,EF was the highest at 35m,There has significant differences between post exercise 35m and rest.At the time,△EF of volunteers was higher than patients with CAD risk factor.Cuing:the store of heart of patients with CAD risk factor was lower than that of volunteers.②There were no volunteers that EDV and ESV diversity was ascend,but there were 7.69% and 15.38%subjects respectively' EDV at post exercise 15m and 35m in groupⅡascending, The ESV of 23.08%and 30.77%were ascend at post exercise 15m and 35m in groupⅡ.Cueing:Diversity of EDV and ESV may an index of evaluating the store of heart for patients with CAD risk factor③EDV and ESV were descending at early imaging phases;EDV at post exercise 15m was significant lower than rest.