Phase analysis of radionuclide angiography in acute myocardial infarction

Standard deviation of the histogram of left ventricular phase distribution (SDP-LV) obtained by radionuclide angiography (RNA) was studied in 75 acute myocardial infarction (AMI) patients, 37 with anterior or anteroseptal (Group A) and 38 with inferior, inferolateral or posterior necrosis (Group I). In order to evaluate sensitivity, specificity and accuracy of SDP-LV compared to ejection fraction (EF) and peak filling rate (PFR), 16 controls and 29 patients with coronary artery disease with normal kinesis proved by angiogaphy were studied. Patients were also compared according to normal or abnormal EF and PFR. Sensitivity of PFR was better than those of EF and PFR (86.6% vs 38.7% and 70.6%, respectively). Specificity of SDP-LV was 89.6%, better than that of PFR (58.6%), but just less than that of EF (93.1%). The accuracy of SDP-LV turned out to be better than those of EF and PFR (87.5% vs 53.8% and 67.3%, respectively). Ejection fraction correlated with SDP-LV in the total study population (r=-0.54, P <0.001), and in Groups A (r=-0.44, P <0.01) and l (r=-0.43, P <0.05); SDP-LV correlated with PFR in the total population (r=-0.35, P <0.05), but not in Group A or I. Mean SDP-LV was higher in Group A than I and in patients with lower EF; no difference was found among patients with different PFR values. No difference in SDP-LV values was found in patients with different EFs between Group A and I; SDP-LV was always higher in Group A than 1, when patients were divided according to different PFR. Thus, SDP-LV abnormalities are detectable in AMI patients and are related to EF; SDP-LV at rest shows better sensitivity and accuracy than EF and PFR, and therefore, in the early course of AMI, adds helpful information about the diagnosis of myocardial necrosis.