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To evaluate the clinical significance of reversible perfusion defects that were observed soon after the successful deployment of a coronary stent, 47 patients underwent thallium-201 myocardial scintigraphy and radionuclide angiography in conjunction with adenosine-induced coronary hyperemia before and after complete revascularization. Coronary angiography showed a significant decrease in the percent diameter stenosis (from 87+/-11% before stenting to -1+/-5% after stenting, p

We investigated the presence of subclinical left ventricular dysfunction by determining left ventricular diastolic filling at rest and the left ventricular ejection fraction (LVEF) response to exercise with radionuclide angiography. The subjects were 40 patients with non-insulin-dependent diabetes who showed no evidence of cardiovascular disease based on clinical findings, electrocardiography and 201 Tl perfusion scintigraphy. We also used 123 I-metaiodobenzylguanidine ( 123 I-MIBG) scintigraphy to investigate whether subclinical left ventricular abnormalities were related to adrenergic cardiac dysinnervation. The change in LVEF in response to exercise (ALVEF) was

We investigated whether the depressed cardiac response to adrenergic stimulation is accompanied with impaired autonomic function in mildly symptomatic patients with idiopathic dilated cardiomyopathy (DCM). Twenty-seven patients with DCM (New York Heart Association class I or II) and 7 normal control subjects underwent exercise radionuclide ventriculography and 24-h ambulatory ECG. The following frequency components of heart rate variability were calculated: the areas under the low (low frequency component [LF], 0.04 to 0.15 Hz), high (high frequency component [HF], 0.15 to 0.40 Hz), and total frequency portions of the spectrum. HF and HF% (the ratio of HF to total power) were calculated as indexes of specific vagal influences, and LF% (the ratio of LF to total power) and the ratio of LF to HF were of sympathetic tone. The left ventricular ejection fraction (LVEF) increased by more than 5% in all normal control subjects during exercise, whereas 17 (63%) of patients failed to show more than a 5% increase in LVEF. The profile of the mean hourly HF% and LF/HF showed circadian variations in normal control subjects but not in patients. The HF and HF% during sleep were significantly lower and the LF/HF during sleep was higher in patients than in normal control subjects. In patients, the LVEF during exercise minus LVEF at rest was significantly correlated with HF, LF%, and LF/HF during sleep, and with the ratios of the mean values during early morning to the mean daytime values for those spectral indexes. Our results demonstrated that mildly symptomatic patients with DCM showed an attenuated cardiac response to exercise and altered autonomic function, and their close relationship, suggesting that autonomic nervous activity contributes to cardiac desensitization in DCM.

The purpose of this study was to assess the effect of adenosine-triphosphate (ATP) on hemodynamics and left ventricular (LV) function, and to examine the value of ATP radionuclide-ventriculography (RNVG) for detecting coronary artery disease (CAD) in comparison with standard exercise RNVG. Thirty-eight consecutive patients with suspected CAD underwent ATP (0.18 mg/Kg/min) RNVG and symptom-limited exercise RNVG. Coronary angiography revealed 27 patients with CAD (Group S) and 11 without CAD (Group N). In group S, exercise induced an increase in LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV), and a decrease in LV ejection fraction (LVEF). In contrast, ATP infusion caused LVESV to decrease in both groups, improving LVEF. Only 14 of 39 segments whose wall motion was deteriorated by exercise showed worsening regional wall motion during ATP infusion. The sensitivity and specificity of ATP RNVG for detecting CAD were 22.2% and 100%, while those of exercise RNVG were 77.8% and 81.8%, respectively. Although ATP induced a depression of peak filling rate in group S as compared with group N, the deterioration of systolic function was not apparent with this method. ATP RNVG was not adequate for detecting CAD because of its lower sensitivity compared with exercise RNVG.

To clarify how angiotensin converting enzyme inhibition affects left ventricular function through ventricular unloading, ventricular wall stress, ventricular volumes, and other cardiac indices and exercise tolerance were evaluated in 17 patients with mild to moderate chronic congestive heart failure before and after 3 months of treatment with enalapril. Echocardiographic examination revealed that treatment with this angiotensin converting enzyme inhibitor resulted in significant reductions in end-systolic wall stress (117 +/- 25 to 89 +/- 28 g/cm2, p < 0.01) and left ventricular volume indices (end-diastolic: 163 +/- 56 to 143 +/- 60; end-systolic 99 +/- 51 to 77 +/- 57 ml/m2 p < 0.01). Ejection fraction (42 +/- 11 to 48 +/- 13%, p < 0.01) and systolic blood pressure/end-systolic volume (SBP/ESV; 1.06 +/- 0.30 to 1.33 +/- 0.48 mmHg/ml, p < 0.01) were both increased. By radionuclide ventriculography, ejection fraction and peak ejection rate (2.30 +/- 0.74 to 2.80 +/- 0.76 EDV/sec, p < 0.01) were increased, while time to peak ejection, time to peak filling, and peak filling rate were unchanged. Heart rate and double product at exercise were decreased and delta EF was significantly increased (-1.4 +/- 4.1 to 1.6 +/- 4.4%, p < 0.02). The decrease in end-systolic wall stress was consistently related to both the increase in ejection fraction and SBP/ESV, while the decrease in end-diastolic volume was related only to SBP/ESV and not to ejection fraction. Furthermore, there was a direct relationship between the decrease in systolic wall stress and the decrease in end-diastolic volume.(ABSTRACT TRUNCATED AT 250 WORDS)

We reported a case of sarcoidosis manifesting with diffuse small nodular lesions in the spleen on CT and MRI. These lesions showed low signal intensity on T2 weighted MRI. Following intravenous contrast material administration, CT and Ti weighted MRI demonstrated them as poorly enhanced lesions in the spleen. In a case of diffuse small nodular lesions, differentials include microabscesses, malignant lymphoma, and Gamma-Gandy nodules. Because these may show findings similar to this case, accurate differential diagnosis is essential.

Serial examination of the electrocardiograms of a 69-year-old man with autopsy proven dilated cardiomyopathy revealed gradual prolongation of the PR interval and development of Q waves in leads II III and aVF over the post last 3 years. On the vectorcardiogram, the QRS loop was gradually distorted and displaced posteriorly in the horizontal plane during the follow up period. Thallium-201 myocardial scintigram revealed perfusion defect of the entire left ventricle, except the lateral wall, consistent with diffuse myocardial fibrosis at autopsy. We thought that gradual loss of electromotive force of the left ventricle resulting from extensive myocardial fibrosis and progression of the intraventricular conduction disturbance might be responsible for the serial electrocardiographic and vectorcardiographic changes in this case.

The diagnostic values of adenosine, dobutamine, and exercise radionuclide ventriculography (RNVG) in the detection of coronary artery disease (CAD), and the characteristics of those patients who showed myocardial ischemia during the infusion of adenosine or dobutamine were assessed in 41 patients with suspected CAD. Sensitivity, specificity, and accuracy, respectively, for detecting patients with CAD were 35 (p < 0.01 vs. exercise RNVG), 100 and 46% (p < 0.01 vs. exercise RNVG) with adenosine RNVG, 74, 100 and 78% with dobutamine RNVG and 88, 71 and 85% with exercise RNVG. There was a significant difference in physiologic parameters during the provocation of ischemia by adenosine versus exercise RNVG, although these parameters were similar by dobutamine and exercise RNVG. Stepwise discriminant analysis revealed that the number of stenotic vessels was an important and independent predictor for the myocardial ischemia induced by each stress; the peak filling rate was the only predictor for adenosine-induced ischemia. Dobutamine induced myocardial ischemia in a way similar to that of exercise, and was more useful than adenosine for pharmacologic stress RNVG. The mechanism of the adenosine-induced ischemia seemed to differ from that of the ischemia induced by dobutamine or exercise, and to be closely associated with left ventricular diastolic function.

The clinical applicability and usefulness of diagnostic procedures in nuclear cardiology have been briefly reviewed, and personal experiences in this field were presented.

Myocardial T1-201 Washout rates (WORs) after exercise stress were measured in 15 normal subjects and 67 patients with coronary artery disease (CAD) or chest pain syndrome and the usefulness of WOR for the detection of CAD was studied.Myocardial tomograms were obtained both immediately after exercise and 3 hours later using a rotating gamma camera in 15 normal subjects and 67 patients. After low-pass filtering, images were reconstructed into short-axis, horizontal long-axis and vertical long-axis tomograms and visually interpreted. By using short-axis tomograms, left ventricle WORs were expressed as circumferential profile curves at the apex, center and base of the ventricle. Lower normal limits of the WOR were set at 2 SDs from the mean of the normal subjects. The combination of visual interpretation of SPECT with WOR increased the sensitivity of detection of CAD from 8.3% to 66.7% in patients with three-vessel CAD without losing specificity.WOR after exercise stress is believed to be a useful method of detecting multivessel CAD.

The purpose of this study is to determine whether the lipoperoxidation is playing a significant causative role in adramycin cardiomyopathy.Cardiac alterations with characteristic histologic changes such as vacuolizations of myocardial cells, myolysis and the interstitial fibrosis developped in rabbits when 2. 5 mg/kg of adriamycin was intravenously administered once a week for 8 weeks. Blood and cardiac malondialdehyde was significantly increased in these animals. Although daily administrations of 50 mg/kg of alpha tocopherol, a free radical scavenger, obviously suppressed the increase of blood and cardiac malondialdehyde, the development of cardiac lesions could not be prevented by this drug.The present observations may suggest that the lipoperoxidation is a result and not a cause of adriamycin cardiomyopathy.

A follow-up study of 196 patients with atrioventricular block and long-term cardiac pacing revealed that the presence of congestive heart failure, cardiomegaly, significant coronary sclerosis and the advanced age were the important factors in a worsening prognosis. On the other hand, no prognostic factors were identified in sick sinus syndrome.Forty of 275 patients with long-term cardiac pacing died during the last 12 years. Thirty-one died within three years after the implantation of the cardiac pacemaker. The leading cause of death was congestive heart failure (13 cases), followed by cerebro-vascular accidents (12 cases), sudden unexpected death (five cases), malignancies (five cases) and acute myocardial infarction (two cases).

A newly developed blood pool agent 99mTc-DTPA-HSA (Japan Mediphysics, Inc.) was used for ECG gated blood pool scintigraphy. The radiopharmaceutical remained in the blood pool with disappearance half time of 420 min in a healthy subject. The gated blood pool study in the same subject clearly demonstrated contracting left ventricle and right ventricle both with planar and SPECT images. Three healthy volunteers and 14 patients were included in the study, in that gated blood pool images were successfully obtained. The left ventricular ejection fraction (LVEF) calculated by the analysis of LV volume curves correlated well with those obtained by echocardiography (US). In 11 patients with implanted pacemaker for complete atrioventricular block and sick sinus syndrome changes of LVEF were evaluated in relation to pacing rates. The mean LVEF at pacing rate of 60/min was 58.5%, which decreased to 54.4% at 100/min pacing rate. However, changes of LVEF in individual patient did not show same pattern. We conclude that 99mTc-DTPA-HSA is a convenient blood pool scanning agent which does not require time consuming labeling preparations. Stable labeling and slow blood clearance allows its use for repeat measurements of LVEF in different conditions in a patient such as with pacemaker.

Radionuclide angiographic measurements of left ventricular ejection fraction were performed at rest and during exercise in 10 normal persons and 11 patients with coronary artery disease. Exercise was continued on a supine bicycle exercise table up to a symptom-limited maximum. Plasma levels of atrial natriuretic peptide (ANP) were also determined at rest and during exercise. Ejection fraction in the normal volunteers was 59 +/- 3% (mean +/- SEM) at rest and increased significantly (p less than 0.01) to 69 +/- 3% during exercise. Ejection fraction in the patients was 47 +/- 5% at rest and did not change significantly during exercise (51 +/- 7%). Plasma ANP in the normals rose significantly (p less than 0.01) from 62 +/- 16 pg/ml at rest to 454 +/- 94 pg/ml during exercise. Plasma ANP in the patients also rose significantly (p less than 0.01) from 231 +/- 102 pg/ml to 794 +/- 170 pg/ml. The response of plasma ANP to exercise was enhanced significantly (p less than 0.05) in the patients as compared with the normals in relation to ejection fraction by analysis of covariance. In both the normals and the patients, plasma ANP was inversely and significantly correlated with ejection fraction during exercise (r = -0.46, p less than 0.05, n = 21), however, not at rest. Because it has been reported that plasma ANP is correlated positively with pulmonary artery wedge pressure, the estimation of plasma ANP during an exercise stress test might be used for the evaluation of cardiac reserve in coronary artery disease.

心房細動,脳塞栓を合併した,本邦における最高令の三心房心の1例を報告する.症例は54才の男性で, 34才頃より労作時呼吸困難を自覚, 43才時心拡大と心房細動より僧帽弁狭窄症を疑われ精査を受けたが,原因は不明であつた. 51才時突然の意識消失,左半身不完全麻痺にて脳塞栓と診断された.昭和56年2月,労作時呼吸困難増悪のため入院.心尖部に拡張期雑音が聴取され,胸部X線像では心胸郭比59%で,左第3弓の直線化および右第2弓の突出を認めた.心電図は心房細動で,平均電気軸は-20°, V1誘導でrSR′パターンを認めた.断層心エコーにて左房内に異常隔壁エコーを認め,僧帽弁には異常は見られなかつた.左房造影像でも同様に左房内隔壁を認め,肺静脈はすべて隔壁上部のaccessory chamberに流入していた.又,心内短絡の合併は認めなかつた.以上よりclassic cor triatriatumと診断し,左房内隔壁切除が行なわれた.隔壁には大きさ約1cm2の交通孔が左心耳直上に認められた.これまでの本邦報告37例のうち,本症例は最高令であり,又脳塞栓合併の報告は他に見られていない.