Search

Forty-four patients with effort angina pectoris were evaluated with SUNY4001 (adenosine) thallium-201 (201Tl) myocardial scintigraphy to detect coronary artery disease. These patients had single-vessel disease (> or = AHA 90% stenosis) in either RCA or LAD. Adenosine was infused at the rate of 120 or 140 microg/kg/min for six minutes. 111 MBq of 201Tl was injected after three minutes of the start of the infusion. The early and delayed images were obtained by SPECT imaging. The sensitivity was 94.7% at 120 microg/kg/min and 84.2% at 140 microg/kg/min. Adenosine 201Tl myocardial scintigraphy showed high accuracy for detecting significant coronary artery disease. Adverse reactions occurred in 77.3% of the patients. Regarding the rates of the adverse reactions, there was no significant difference between 120 and 140 microg/kg/min. Major adverse reactions were Chest pain/discomfort (52.3%) and Flushing/Feeling of warmth (27.3%). No serious complication was observed at any infusion rate. Most of adverse reactions disappeared sortly. Only two patients required treatment for moderate chest pain, which, however, disappeared in several minutes. One of the treatments was merely the termination of adenosine infusion, and the other was sublingual spray of nitroglycerin. Adenosine infusion caused slight decrease in blood pressure and increase in heart rate. The hemodynamic changes resolved within several minutes after the adenosine infusion. Decrease in systolic blood pressure of more than 20 mmHg from the base level occurred in 26.1% and 52.4% at 120 and 140 microg/kg/min infusion rate respectively. Therefore, the adenosine infusion at 120 microg/kg/min should be considered safe and useful for the diagnosis of coronary artery disease by pharmacologic stress imaging.

We compared the ischemic diagnosis ability and adverse events of 201Tl myocardial perfusion imaging with SUNY4001 (adenosine) stress to that with exercise (ergometer) stress both on random crossover trial. Thirty one known or suspected chronic stable angina patients who are able to exercise and 10 healthy volunteers were enrolled for the trial. The early and delayed images were obtained by SPECT imaging. The concordance of diagnoses [ischemia vs. no ischemia] between the two types of stresses was 97.3% (36/37) [Kappa: 0.9068]. The sensitivity and specificity based on the exercise test were 100% (6/6) and 96.8% (30/31) respectively. The incidence of adverse events caused by SUNY4001 and the exercise were 44.7% (17/38) and 52.6% (20/38), respectively. Major adverse events caused by SUNY4001 were BP decrease, flushing and headache. And those by exercise were ST decrease, dyspnea and chest pain. None of the adverse events required the intervention or caused life-threatening complication in the trial. The trial showed that the ischemic diagnosis ability and safety of 201Tl scintigraphy with SUNY4001 stress are almost equal to those of the exercise stress that is considered as the standard stress method. We concluded that 201Tl imaging with SUNY4001 is safe and useful for detecting ischemic heart disease, especially for patients unable to exercise adequately.

With two hundred and seven patients unable to exercise adequately, the diagnostic accuracy and adverse reaction of 201Tl myocardial scintigraphy with the pharmacologic stress by SUNY4001 (adenosine) infusion were studied. Adenosine was infused for six minutes at the rate of 120 microg/kg/min, and then 201Tl was injected after three minutes from the start of infusion. The early and delayed images were obtained by SPECT imaging. According to angiography, > or = AHA 90% stenosis was defined as significant. The sensitivity of detecting coronary artery disease was 87.1% and the specificity was 46.0%. Adverse reactions occurred in 66.7% of the patients, most of which disappeared shortly with no need for treatment. Major adverse reactions were chest pain/discomfort (30.4%), flushing/feeling of warmth (22.4%) and blood pressure decrease (17.4%). Adenosine infusion caused slight decrease in blood pressure and increase in heart rate. These hemodynamic changes were resolved within several minutes from the termination of adenosine infusion. We concluded that adenosine-201Tl imaging is safe and useful to detect coronary artery disease in patients unable to exercise adequately.

We performed BMIPP myocardial SPECT and Tl myocardial SPECT in patients with unstable angina (UAP) and stable effort angina (SAP), and compared the results for the two groups. Our subjects were 30 patients with the UAP and 25 patients with the SAP. The early and delayed images of the BMIPP were obtained with patients at rest. The early image of the Tl alone was obtained with patients at rest. We calculated severity score (SS) using the polar map based on SPECT short-axis image on the both myocardial SPECT. And, we calculated % uptake of the responsible coronary lesion and regional washout rate (WR) on myocardial SPECT with BMIPP. On coronary angiogram, no difference in % diameter stenosis was seen between the two groups. On myocardial SPECT with Tl, no difference in the SS was seen between the two groups. However, on myocardial SPECT with BMIPP, the SS was significantly higher score in the UAP group than in the SAP group. And, on myocardial SPECT with BMIPP, the % uptake and the WR were significant lower values in the UAP group than in the SAP group. Even if the two groups have almost the same level of myocardial perfusion disorder, the UAP group may have severer myocardial fatty-acid metabolic disorder than the SAP group, because the defects in BMIPP were significantly severer in the UAP group.

We investigated prediction of the efficacy of beta-blocker therapy in patients with dilated cardiomyopathy (DCM) by using myocardial scintigraphy with 123I-BMIPP (BMIPP) and 123I-MIBG (MIBG). Thirty-seven patients with DCM were examined by myocardial scintigraphy with BMIPP and MIBG before beta-blocker therapy. Patients were classified into two groups, based on whether they improved > 10% of the left ventricular ejection fraction (LVEF) (improved group, n = 21) or not (unimproved group, n = 16). The extent and severity score of BMIPP for the improved group was significantly lower (p < 0.001) than that for unimproved group. It has been suggested that BMIPP is useful in evaluating the prediction of efficacy of beta-blocker therapy in patients with DCM.

We sent out a questionnaire to investigate how the 99mTc-labeled myocardial perfusion agents are used in the Kanto-Koshinetsu area. Answers were obtained from 83 laboratories. Examinations using 99mTc-labeled agents were performed more frequently than those using 201T1 only in 10 of 83 laboratories. Main reasons for not using 99mTc-labeled agents were as follows: two injections required in the stress study, superiority of thallium-201 in the assessment of myocardial viability, a large amount of clinical data cumulated in thallium-201 imaging, and problems caused by abdominal uptake of 99mTc-labeled agents. Comparing purposes of the examinations using 201T1 and 99mTc-labeled agents, evaluation of myocardial viability was more common in 201Tl imaging, meanwhile, detection of myocardial ischemia was more common in imaging with 99mTc-labeled agents. It was pointed out that dual isotope imaging using 201Tl and 99mTc-labeled agents and simultaneous evaluation of myocardial perfusion and cardiac function are clinically feasible as new diagnostic procedures.

123I-BMIPP is a radioiodinated branched chain fatty acid analog, showing high accumulation as well as prolonged retention in the myocardium. Therefore, it is used as a metabolic imaging agent suitable for myocardial SPECT. After 123I-BMIPP is taken in the myocardium, it remains there mainly as a storage type fatty acid of triglyceride, and it shows different behavior by the stage of cardiac disease. Usually, we evaluate metabolic findings by early imaging (20 minutes) after intravenous injection of 123I-BMIPP, however, some times washout or fill in are seen in the case of myocardial infarction or hypertrophic cardiomyopathy by delayed imaging (after 4 hours). The mismatch of 201TlCl and 123I-BMIPP are useful for the diagnosis of stunned myocardium or evaluation of prognosis. However, behavior of 123I-BMIPP in myocardium is known still not completely. Therefore clinical significance of this examination is thought to be clarified by the stock of cases of various heart diseases.

In 29 patients who had been administrated adriamycin (ADR) for the treatment of hematopoietic malignancies, myocardial SPECT was performed 20 minutes and 4 hours after an intravenous dose of 123I-metaiodobenzylguanidine (MIBG). Findings of the myocardial SPECT were compared with the total dose of ADR, ejection fraction (EF) and left ventricular wall motion, as assessed by ultrasound echocardiography. The mean total dose of ADR was 329.3 mg/m2 (range, 150-550 mg/m2). 1) Although the cardiac function was normal, the washout rate (WR) of MIBG was high in 75% of the patients whose MIBG myocardial SPECT showed abnormality on ADR, suggesting the presence of adrenergic nerve disorder. 2) The total dose of ADR was significantly correlated with WR of MIBG (p < 0.001). Consequently, WR of MIBG may be an index which reflects adrenergic nerve disorder in the myocardium earlier than EF. 3) It was suggested that adrenergic nerve disorder was involved in pathogenesis of myocardial complications associated with ADR administration. In summary, MIBG myocardial SPECT could be a useful test for determining a dosage regimen of ADR therapy of individual patients.

MIBG-myocardial SPECT was performed on patients with dilated cardiomyopathy (DCM) undergoing treatment with beta blocker (Nipradilol). The findings of MIBG-myocardial SPECT were compared with the changes in cardiac function obtained by echocardiograms. The patients enrolled in the study were seven males who has been diagnosed as definitely suffering from DCM according to diagnostic guidelines provided by the Ministry of Health and Welfare. The patients were aged 57.5 +/- 10.2 years. Following intravenous administration of 111 MBq (3 mCi) of MIBG, myocardial SPECT was taken 20 minutes, and 4 hours later. The washout rate of the left ventricular wall was higher in the unchanged group (40.7 +/- 1.2%) than in the improved group (30.3 +/- 6.1%). Both the early and delayed images showed higher extent and severity scores for the unchanged group than for the improved group. A correlation of LVEF with the washout rates was demonstrated (r = -0.819, p < 0.05). A correlation was also observed between the variations in LVEF before and after beta blocker therapy with the washout rates (r = -0.969, p < 0.01), MIBG-myocardial SPECT suggested possibility of the evaluation of severity and prognosis in the patients with DCM.

The SPECT unit using a 3 heads camera (PRISM-3000) has an advantage over the conventional one head camera SPECT unit because it can complete full circle scans (360 degrees scans) within a short time, and because the non-circular orbit of the camera heads fitting the individual form of the body has improved the spatial resolution. In addition, the high speed data processing has reduced the time for scan, enabling the three dimensional imaging system clinically applicable. In the present study, this modern technique was used to examined the myocardium in patients with ischemic heart disease so as to evaluate it for usefulness and depict problem to be solved. In patients with myocardial infarction, images obtained with a PRISM-3000 machine could provide more objective information on infarcts than conventional images. In patients with angina pectoris, delayed images obtained 3 hours after exercise by the new method were superior to conventional ones in power of demonstrating redistribution. The setting of the threshold for ischemic lesions at 40-50% hampers the assessment of the severity of ischemia. A new program should be introduced to solve this problem.

We studied 201Tl myocardial scintigraphy and 99mTc-HSA gated blood pool scan to evaluate the influence of growth hormone on myocardial blood flow and hemodynamics in 16 patients with acromegalies. Contraction properties were almost within normal limit, but cardiac output was in high output state, because left ventricular ejection fraction (LVEF), right ventricular ejection fraction (RVEF) and cardiac output were 47.8 +/- 17.1%, 37.3 +/- 14.9%, and 6.4 +/- 1.7 L/min, respectively. Otherwise, 201Tl myocardial images revealed 62.5% no redistributed hypoperfusion, 18.8% redistributed hypoperfusion, 56.3% myocardial hypertrophy and 25.0% left ventricular enlargement. These data suggested the high incidence of acromegalic cardiomyopathy due to primary or secondary growth hormone effect.

A case of cardiac amyloidosis, which was recognized as an ischemic change by exercise Tl-201 myocardial scintigraphy, was studied. The case was 41 year-old woman, whose initial symptom was pretibial edema and died of ventricular fibrillation. Ischemic change was ascertained by the treadmill exercise test and exercise Tl-201 myocardial scintigraphy, however, the significant coronary stenotic lesion was not detected by coronary angiography. Our data suggested that ischemic change may be related with the disturbance of microcirculation caused by deposit of amyloid in the vessels and/or around the vessels from the pathological findings.

We report a case of lung metastatic tumor originated from submandibular osteosarcoma, which shows rare advancement and findings. This lung metastatic tumor advanced from left lower lung to left atrium through the left lower pulmonary vein, which penetrated to the left ventricle in the diastolic phase mimicking left atrial myxoma. 67Ga-citrate images showed that hot accumulation were recognized behind the heart in planar image and clear advancement from the lung to the heart in the SPECT image. 67Ga-citrate SPECT image should be available for cardiac tumors.

The therapeutic effect of intravenous injection of Urokinase (UK method) on acute myocardial infarction (AMI) was studied and compared with the results of the therapeutic effect of PTCR + PTCA. The subjects comprise 108 cases with AMI, and a radioisotope examination was performed in the acute stage to calculate LVEF and Tl-defect ratio (Tl-DR). Measured by the UK method, Tl-DR in the group given 1.2 X 10(6) units of UK was 1.63 +/- 0.8, which was lower than the 2.4 +/- 1.33 for the group given 9.6 X 10(5) unit of UK, whereas a favorable therapeutic effect was obtained in both groups compared to 3.5 +/- 2.5 in the control group. In the group given UK within 6 hours after the onset of AMI, favorable results were obtained for LVEF (44.5 +/- 11.2%) and Tl-DR (1.68 +/- 0.82). The UK group showed as better results as the PTCR + PTCA group for LVEF (42.3 +/- 11.3 vs. 38.1 +/- 7.4) and Tl-DR (2.10 +/- 1.19 vs. 2.09 +/- 0.62). In both the UK and PTCR + PTCA groups, Tl-DR was well maintained despite an increase in the peak CPK and a decrease in LVEF, and, therefore, the conservation of stunned myocardium in the acute stage was suggested. From the above, it was concluded that the UK method is useful for treating AMI.

Application for myocardial imaging and fundamental experiments were studied using straight chain fatty acid analog IPPA [omega-(p-iodophenyl)-pentadecanoic acid]. Biodistribution of IPPA in rabbits (n = 6) shows the accumulation in liver was maintained 81.0% at 30 minutes, while the accumulations of heart, lungs and kidneys were 30.0%, 10.0% and 15.0% respectively. Especially the accumulation of heart decreased rapidly from 48.0% at 3 minutes to 30.0% at 30 minutes, reflecting the effect of beta oxidation. On the other hand, in the acute myocardial infarction mode (n = 6), with occlusion in left anterior descending coronary artery, all 6 cases showed defect images at the corresponding areas after injection of 3 mCi of IPPA. Myocardial imaging with IPPA should be useful not only for myocardial metabolic diseases (cardiomyopathy etc.) but also for ischemic heart disease.

There are not many reports on pulmonary artery aneurysms in Japan. The prognosis of them is unfortunately poor, and surgical treatment should be needed in some cases. We report a case of central pulmonary artery aneurysm diagnosed by 99mTc-HSA angiography.

In order to elucidate the mechanism of left ventricular eccentric hypertrophy in conditions of volume overload, Tl-201 myocardial scintigraphy was performed patients with aortic valve regurgitation and mitral valve regurgitation. There was a good relationship between the severity of Tl-defects, as determined by Tl-201 myocardial scintigraphy, and the changes in the T wave on the ECG on the one hand and the NYHA functional classification of heart diseases. In 17 of 18 patients where LVDd increased with increasing severity of Tl-defects and the defects were moderate to severe, LVDd was 65 mm or larger. There was a significant negative correlation between the washout rate for the whole circumference of the left ventricle, as determined by exercise Tl-201 SPECT, and LVDd (r = -0.603, p less than 0.01). The phenomenon of redistribution as determined by exercise Tl-201 myocardial scintigraphy was observed relatively early. Our results suggest that mechanical volume overload and ischemic changes are involved in left ventricular wall damage in left ventricular eccentric hypertrophy. For patients with moderate to severe Tl-defects valve replacement is indicated, no matter whether they may have heart failure or arrhythmia.