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Y Kanoh

Publications and source records attributed to Y Kanoh.

48 records · Page 3Linked to original sources

[Hypertrophic non-obstructive cardiomyopathy assessed by dipyridamole thallium single photon emission computed tomography: comparisons with hypertrophic cardiomyopathy with a dilated heart].

Thallium-201 (Tl) single photon emission computed tomography (SPECT) after dipyridamole infusion (0.56 mg/kg) was performed in 23 patients with hypertrophic non-obstructive cardiomyopathy (HNCM) and in seven patients with HCM simulating dilated cardiomyopathy (HCM-DCM) to clarify the mechanism and clinical significance of decreased coronary vasodilatory reserve. The coronary vasodilatory reserve in the hypertrophied area assessed by SPECT was compared with the findings of echocardiography, left ventriculography and endomyocardial biopsy. 1. Eleven patients with HNCM had no perfusion defects in the hypertrophied area (group I), but the other 12 patients (52.2%) had such defects (group II). All seven patients with HCM-DCM had perfusion defects in the anterior or septal walls (group III). Redistribution was observed in 11 of the 12 patients in group II and in three of the seven patients in group III. 2. The regional washout rate was relatively low in the upper septum in group II and in the anterior wall and upper septum in group III. Thus, coronary vasodilatory reserve in the hypertrophied area was decreased in groups II and III. 3. Echocardiographically, the degree of hypertrophy did not differ between groups I and II, but the latter had significantly greater left ventricular diastolic dimension (42.3 mm vs 49.5 mm: p less than 0.05) and lower percent fractional shortening (%FS) (43.7% vs 35.6%: p less than 0.05). However, group III showed thinner left ventricular wall, much greater diastolic dimension (60.9 mm vs 49.5 mm: p less than 0.05), and lower %FS (24.0% vs 35.6%: p less than 0.05) than did those of group II. 4. On left ventriculography, those in group II showed larger left ventricular end-diastolic volume index (93.9 ml/m2 vs 79.7 ml/m2: p less than 0.05) than that of group I. Left ventricular ejection fraction showed the same tendency, but this was not statistically significant. 5. On endomyocardial biopsy, the specimens of the patients in group II had significantly higher percent fibrosis than did those of group I (11.4% vs 6.8%: p less than 0.05). These findings suggest that the mechanism of decreased coronary vasodilatory reserve in the hypertrophied area may be related to myocardial fibrosis, and this decrease may induce left ventricular dysfunction and compensatory dilatation.

Adult↗

[Assessment of regional wall motion and myocardial flow in patients with dilated cardiomyopathy using Tl-201 SPECT during dobutamine infusion].

The present study clarified the relationship between wall motion and myocardial flow in dilated cardiomyopathy (DCM). Two-dimensional echocardiography (2-DE) was performed in 14 patients before and after dobutamine (DOB) drip infusion (8 micrograms/kg/min). Thallium-201 emission computed tomography (ECT) was performed after dobutamine infusion and three hours thereafter. The left ventricle was divided into nine segments. In each segment, the degrees of defects were scored from 0 (normal) to 3 (complete defect), and the severity of wall motion abnormalities was scored from 0 (normal) to 3 (akinesis) by visual inspection. 1. Perfusion defects on ECT images were observed during dobutamine infusion in all patients. Redistribution was observed in nine of 14 (64%) patients. 2. During infusion, 38 (81%) of 47 segments without defects showed normal wall motion, but 44 (86%) of 51 segments with defects showed wall motion abnormalities. 3. Redistribution was observed in 18 (35%) of 51 segments, and these segments showed lower incidence of wall motion abnormalities as compared to the other segments (94% vs 45%, p less than 0.001). 4. After infusion, the segments with redistribution frequently showed improved wall motion as compared to the other segments (56% vs 18%, p less than 0.05). These results indicate that redistribution on the ECT image is observed in some patients with dilated cardiomyopathy after dobutamine administration. This may be due to the capacity of the drug to increase myocardial flow in proportion to the increase of oxygen demand.

Cardiomyopathy, Dilated↗

[201T1 computed tomography using dipyridamole for assessing dilated cardiomyopathy].

The value of redistribution thallium-201 (T1-20(1] emission computed tomography (ECT) using dipyridamole for evaluating coronary circulation was analyzed in 18 patients with dilated cardiomyopathy (DCM). After maximal inducible coronary vasodilation (dipyridamole, 0.56 mg/kg), 2 mCi T1-201 was administered, and dipyridamole ECT data at 10 minutes and delayed ECT data at 3 hours after the injection were collected. Image interpretation was made visually. The results were as follows: In all cases, perfusion defects were observed on the dipyridamole images, and eight (45%) had redistribution on their delayed images. Patients with redistribution had better left ventricular function (% fractional shortening 24.7 +/- 7.0 versus 18.0 +/- 5.0) by two-dimensional echocardiography. Segments with redistribution showed less severe wall motion abnormalities compared with segments without redistribution. It is concluded that redistribution thallium ECT imaging using dipyridamole is a useful tool for the evaluation of coronary circulation of patients with DCM.

Cardiomyopathy, Dilated↗

[Clinical significance of early redistribution of the exercise-induced thallium-201 defect in ischemic heart disease].

This study clarified thallium-201 (Tl) kinetics in the early stage after exercise in patients with ischemic heart disease (IHD). Tl was administered for 39 patients with IHD and eight normal subjects during maximal exercise. Immediately after exercise, dynamic data were obtained using a double slant-hole collimator at one frame/2 min for a 20 min period. The data of 10 frames (20 min) were spatially smoothed, and semiquantitative segmental analyses of the uptake and kinetics of Tl were performed by computer. In eight normal subjects, Tl uptake was uniform throughout the continuous 20 min, and Tl activity was unchanged throughout the 20 min period after exercise. Among 39 patients with IHD, 39 had Tl defects in the first frame (initial defect). Among 39 initial defects, 15 (38%) showed complete or partial early redistribution as early as 20 min and Tl activity in the defect increased (10.5 +/- 1.5%) over the 20 min period. Early redistribution occurred in 10 (43%) of 23 patients with effort angina and in five (83%) of six patients with variant forms of angina, but in no patients with myocardial infarction. Patients with early redistribution showed a greater frequency either of good collateral vessels or of mild stenosis of the coronary artery, compared with those who had no early redistribution. In conclusion, analysis of Tl kinetics in the early stages after exercise can provide important information about the coronary perfusion state during recovery from transient ischemia, and early redistribution may be a sign of preserved hyperemic flow in the ischemic region.

Angina Pectoris↗

Progression of prostate cancer: diagnostic and prognostic utility of prostate-specific antigen, alpha2-macroglobulin, and their complexes.

We previously reported cases of advanced prostate cancer (PCa) in which serum alpha2-macroglobulin (alpha2M) levels were markedly decreased to less than approximately 50 mg/dl whereas serum prostate-specific antigen (PSA) levels were remarkably increased. These cases were not complicated with disseminated intravascular coagulation (DIC). In this study, we measured serum PSA and alpha2M in 108 patients with either benign prostatic hyperplasia (BPH) or PCa to elucidate the relationship between PSA, i.e. the serum protease derived from the prostatic tissue, and alpha2M, i.e. the protease inhibitor that was the most abundantly contained in serum. alpha2M was determined by ELISA, total PSA and PSA-alpha1-antichymotrypsin (PSA-ACT) by EIA, and free-PSA by RIA in 44 patients with untreated BPH and 64 patients with untreated PCa. The ready association of alpha2M and PSA was assessed using Western blotting to identify complexes of the two. Levels of total serum PSA correlated positively with those of PSA-ACT in PCa (r = 0.99, p < 0.001), and both levels increased with advancing stage of disease. In contrast, the serum-free PSA/total PSA ratio (free/total PSA) and alpha2M levels decreased as the disease progressed. However, only the free/total PSA ratio attained significant difference for localized cancer in stage T1,2 versus BPH (p < 0.05). In stage M1b PCa, in which serum PSA levels were very high, there was a negative correlation between the total PSA and alpha2M values (r = -0.57, p < 0.05). In addition, serum alpha2M levels tended to decrease with progression of PCa. Serum total PSA levels correlated tightly with serum PSA-ACT levels. It is suggested that PSA is usually complexed with ACT in the serum. Free/total PSA was useful for differential diagnosis between early cancer and BPH. Levels of serum alpha2M of less than 50 mg/dl in PCa patients may indicate a possibility of bone metastases.

Aged↗

Levels of alpha 2 macroglobulin can predict bone metastases in prostate cancer.

BACKGROUND: In prostate cancer, we previously reported that a marked decrease of serum alpha 2 macroglobulin (alpha 2M) to less than approximately 50 mg/dl was associated with the presence of bone metastases. In order to investigate the relationship between bone metastases and alpha 2M, we assessed these two parameters in 128 patients with prostatic diseases. MATERIALS AND METHODS: 66 patients with untreated benign prostatic hypertrophy and 62 with untreated prostate cancer were included in the study. Measurement of alpha 2M concentration was performed by Laser-Nephelometry, prostate-specific antigen (PSA) by EIA. RESULTS: The serum alpha 2M levels in prostate cancer with bone metastases showed a significantly lower level compared with the group without bone metastases (p < 0.01). Cases with serum alpha 2M levels of less than 50 mg/dl all had bone metastases. Serum alpha 2M levels were inversely related to PSA levels in stage M1b disease. CONCLUSIONS: Measurement of serum alpha 2M levels may be useful for the diagnosis and follow up of bone metastases in prostate cancer.

Adenocarcinoma↗