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Background: The aim of the study was to evaluate the relationship between myocardial viability (MV) detected by Tl‐201 rest/redistribution protocol (RR‐SPECT) and the presence of ventricular late potentials (VLPs) in acute myocardial infarction (AMI). We analyzed signal‐averaged ECGs (SAECGs) in 28 patients (age 57 ± 10 years) with a first anterior AMI within 48 hours of symptoms (SAECG1) and prior to discharge (SAECG2). VLPs were defined according to the presence of filtered QRS (QRS‐D) > 114 ms and duration of low amplitude signals (LAS) a 30 ms or root mean square voltage (RMS40) < 25 μ;V, using a 25‐Hz filter, or a duration of LAS > 39 ms or RMS40 < 20 μ;V, using a 40‐Hz filter. RR‐SPECT was performed 17 ± 6 days after AMI. Segments were considered viable when counts were > 60% in early images or when a fill‐in > 10% was detectable on delayed images of those segments with a first count between 31% and 59%.

We studied the effects of glucose, insulin, and KCI infusion (GIK), on regional myocardial perfusion and function by 99m-Tc-tetrofosmin-gated SPECT.Methods- we studied 21 male patients with their first uncomplicated acute myocardial infarction (AMI). All patients underwent a rest and submaximal stress perfusion study before and after 24-hour infusion of GIK-solution (group A) or saline solution (group B).Results- Group A showed better stress tolerance and ischaemic threshold improvement after GIK infusion whilst no statistical differences were found between basal and post-infusion test in group B.At first the stress test in group A, of the 192 segments analysed, 52 (27%) showed reversible perfusion defect. In group B, of 144 segments analysed, 31 (21%) showed reversible perfusion defect. A postinfusion analysis in group A showed a post-GIK end-diastolic significant count improvement in 21 segments, and a post-GIK end-systolic count improvement in 22 segments. In group B, perfusion increase was observed only in 4 segments, whilst systolic thickening increase was observed only in I segment.Conclusion- these data demonstrate the efficacy of GIK infusion to improve regional myocardial perfusion and function mainly in segments adjacent to the recently infarcted area.

In order to compare the reliability of hepatobiliary scintigraphy using DISIDA (DHS) and ultrasonography (US) in the diagnosis of obstructive jaundice, 36 consecutive patients clinically suspected for obstruction were examined with both methods. Sixteen patients who were definitively shown to have obstruction, were all correctly detected with DHS; US was positive in 15 cases, revealing the cause of the obstruction in four cases. The site of obstruction was predicted in eight cases by DHS, and in 11 cases by US. Associated gallbladder diseases were evaluated better by US than by DHS, but a perforation was only demonstrated clearly by DHS.

The aim of this study was to directly compare three currently used quantitative methods of analysis of technetium-99m sestamibi images in patients with selective balloon-induced transmural ischaemia. The area at risk (AR) was assessed in 19 patients undergoing singlevessel percutaneous transluminal coronary angioplasty by injecting the99mTc-sestamibi at the time of coronary artery occlusion during balloon inflation. After imaging, the patients were classified according to localization of the perfusion defect as having anteroseptal (group I, 11 patients) or posterolateral defects (group II, eight patients). The planimetric technique based on polar maps, proposed by Verani et al. (J Am Coll Cardiol, 1988) (method A), the method described by Tamaki et al. (Circulation, 1982) (method B) and the technique validated by O'Connor et al. (Eur J Nucl Med, 1990) (method C) were tested. Three threshold values of 45%, 50% and 60% of the maximum left ventricular count were used to define the limits of the perfusion defect. The mean values of the AR calculated by the three techniques with the original cut-off level (method A=16.5%±12.9; method B=10.4%±7.6%; method C=29.6%±15.7%) were statistically different (one-way analysis of variance:P<0.001; pairedt test: method A vs B,P=0.003; method B vs C and method A vs C,P<0.0001). There was no significant difference between the mean values of the AR estimated by the three methods using the same cut-off levels. The use of 60% of the maximum left ventricular count provided the best correlation between the techniques (method A vs B,r=0.95; method B vs C,r=0.92; method A vs C,r=0.95). Nevertheless, a difference >10% between the values of AR assessed by the three methods was found in four subjects. There was no significant difference between the three methods in the evaluation of AR in the subjects of group I and group II. Reproducibility was good for all methods. It is concluded that the three methods of analysis of the AR by99mTc-sestamibi SPET imaging showed comparable performance and good reproducibility using the same cut-off level. The location of perfusion defect does not affect the comparability of the three techniques. We suggest the use of a cut-off level of 60% for all three methods in the assessment of the AR by99mTc-sestamibi SPET imaging.

We studied 33 patients (28 males, 5 females) with first inferior acute myocardial infarction (AMI) and 12 normal volunteers. They underwent first-pass (FP) and equilibrium-gated radionuclide angiography (EGRA) within 4 days of the onset of symptoms. The parameters [ejection fraction (EF), peak ejection rate (PER), peak filling rate (PFR)] of the time-activity curve (TAC) of both ventricles [left ventricle (LV), right ventricle (RV)] were computed. The regional wall motion (RWM) was evaluated by parametric images (amplitude and phase). In 43% of the patients with AMI, we found a depressed RVEF, while the LVEF was decreased in only 33%. The sensitivity of diastolic parameters was shown to be clearly superior to that of the systolic parameters (RVPFR, 78%; LVPFR, 79%). The abnormalities of the overall performance of both ventricles were significantly correlated with those of the RWM. The abnormal RVEF allwed us to assess the necrotic involvement of the RV, while a depressed RVPFR suggested an impaired RV compliance mostly on an ischemic basis. Congestive heart failure (CHF) and shock syndrome were significantly correlated with depressed RV parameters, while the LVEF, despite RWM abnormalities, was in the normal range. EGRA with computation of the TAC parameters of both ventricles appeared to be useful for in-hospital prognostic evaluation, therapeutic planning and clinical follow-up of patients with inferior myocardial infarction.

Two methods for the analysis of left ventricle time-activity curve (TAC) of equilibrium gated ventriculography were compared in three groups of subjects [8 controls, 13 patients with coronary artery disease (CAD), 11 patients with myocardial infarction (MI). The first method was based on third-degree polynomial fitting, the second on Fourier analysis. The following parameters were calculated: peak ejection rate (PER), peak filling rate (PFR), time to PER and PFR, and filling fraction at the first third of diastole.

A method for comparative measurement of hepatic clearance of different hepatobiliary agents is described and the clinical use of diethyl-IDA and parabutyl-IDA is discussed. The study was performed with both radiopharmaceuticals in 13 patients with hepatobiliary disease with serum bilirubin ranging from 0.3 to 16.4 mg/100 ml.

The purpose of this study was to assess the clinical usefulness of phase and amplitude images and of the left ventricle time-activity curve (LVTAC) obtained by equilibrium gated radionuclide ventriculography (EGRV) in patients with acute myocardial infarction (AMI).

A case of left atrial myxoma shown on an equilibrium radionuclide ventriculography is presented. A peculiar abnormality of the Fourier phase image appears more reliable than the other findings previously revealed by first-pass or equilibrium studies. The findings were perfectly consistent with the gross anatomy of the tumour.