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Y Shimono

Publications and source records attributed to Y Shimono.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Serial change of 123I-BMIPP SPECT imaging during recovery from stunned myocardium after acute myocardial infarction--correlation with 201Tl and two-dimensional echocardiography].

Using 123I-beta-methyl iodophenyl pentadecanoic acid (123I-BMIPP), we investigated changes in myocardial fatty acid metabolism at recovery from stunned myocardium after acute myocardial infarction (AMI), correlation with recovery of regional wall motion and thallium-201 (201Tl) distribution in particular. The subjects were 15 patients who underwent successful reperfusion therapy after the first onset of AMI. None of the patients had multi-vessel disease or ischemic episode during their clinical course. Patients underwent 123I-BMIPP scintigraphy, 201Tl scintigraphy and two-dimensional echocardiography during the acute and chronic phases. Then, we compared regional wall motion with distribution of 123I-BMIPP and 201Tl. Regional wall motion and SPECT were evaluated by the established 16 segment model. In patients, showing serial improvement in regional wall motion, there was 80.0% (8/10) showed normal 201Tl distribution during the acute phase or normalized during the chronic phase. However, distribution of 123I-BMIPP normalized only in 10.0% (1/10) of this group. In examination of each segment that showed serial improvement in regional wall motion, 92.3% (24/26) of these segments showed normal distribution of 201Tl during the acute phase or normalized distribution during chronic phase, despite distribution of 123I-BMIPP improved in only 3.8% (1/26) of these segments. These indicate that, in the process of recovery from myocardial stunning after AMI, abnormal distribution of 123I-BMIPP continued longer than abnormal distribution of 201Tl.

Decanoic Acids↗
PubMed1993

Is ST segment re-elevation associated with reperfusion an indicator of marked myocardial damage after thrombolysis?

OBJECTIVES: The significance of ST segment re-elevation at reperfusion by thrombolysis was evaluated. BACKGROUND: The significance of ST re-elevation has not been studied. Hence, we evaluated whether ST re-elevation is an indicator of marked myocardial necrosis after reperfusion. METHODS: Twelve-lead electrocardiograms were recorded serially, before thrombolysis and immediately after each coronary angiographic procedure during thrombolysis. RESULTS: In 32 patients with acute myocardial infarction, 15 showed transient ST re-elevation at reperfusion (group 1) and 17 showed reduction (group 2). Peak creatine kinase (CK) and CK-MB isoenzyme activity levels were significantly higher in group 1 than in group 2. Twelve patients in group 1 had strongly positive findings on early technetium-99m pyrophosphate scintigraphy, compared with one patient in group 2 (p < 0.001). The regional ejection fraction did not increase from the acute phase to the chronic phase in group 1. The ST deviation before thrombolysis was significantly greater in group 1 than in group 2 (p < 0.001). All 14 patients in group 1 showed Thrombolysis in Myocardial Infarction (TIMI) grade 0 flow and 12 of these patients did not have good collateral flow before thrombolysis. CONCLUSIONS: These data suggest that 1) ST re-elevation at reperfusion is a sign of limited myocardial salvage by thrombolysis, and 2) high ST elevation and TIMI grade 0 flow without good collateral flow before thrombolysis may be predictive variables for marked myocardial necrosis after reperfusion.

Aged↗
PubMed1992

Localization of exercise-induced myocardial ischemia with ST depression.

This study was undertaken to determine whether the site of ST depression on 12-lead exercise electrocardiography can identify the ischemic site assessed by myocardial Tl-201 emission computed tomography in 409 patients with transient defects. ST depression in some leads was more frequent in those with inferior or lateral ischemia than in those with anterior ischemia. In 214 patients with ST depression and no ST elevation, however, the frequency of ST depression in each lead was similar between those with and without anterior ischemia. In 63 patients with ST depression, single vessel disease and no infarction, the frequency of ST depression in each lead was similar among those with anterior, inferior and lateral ischemia. Moreover, in patients with abnormal Q waves, the site of ST depression was not related to the location of ischemia. In conclusion, the site of exercise-induced ST depression could not be used to determine an ischemic region.

Arteriosclerosis↗
PubMed1991

Synthesis of the oligosaccharides alpha-D-Glcp-(1----4)-D-Xylp, alpha-D-Xylp-(1----4)-D-Glcp, alpha-D-Glcp-(1----4)-alpha-D- Glcp-(1----4)-D-Xylp, alpha-D-Glcp-(1----4)-alpha-D-Xylp-(1----4)- D-Glcp, and alpha-D-Xylp-(1----4)-alpha-D-Glcp-(1----4)-D-Glcp.

Syntheses are described of the disaccharides, alpha-D-Glcp-(1----4)-D-Xylp, alpha-D-Xylp-(1----4)-D-Glcp, and alpha-D-Xylp-(1----4)-D-Xylp, and the trisaccharides, alpha-D-Glcp-(1----4)-alpha-D-Glcp-(1----4)-D-Xylp, alpha-D-Glcp-(1----4)-alpha-D-Xylp-(1----4)-D-Glcp, and alpha-D-Xylp-(1----4)-alpha-D-Glcp-(1----4)-D-Glcp as analogues of glucoamylase and soybean beta-amylase substrates.

Carbohydrate Conformation↗
PubMed1991

The scoring system for early technetium-99m pyrophosphate scintigraphy as a method of evaluation of limiting the myocardial infarct size by thrombolysis.

The usefulness of a scoring system with early technetium-99m pyrophosphate scintigraphy as a method for evaluating the efficacy of myocardial preservation after thrombolysis was studied. The mean time from the onset of acute myocardial infarction to injection of the tracer was 5.6 +/- 1.5 h (range 2.8 to 11.9 h). All 36 patients underwent successful recanalization. Patients with strongly positive technetium-99m pyrophosphate uptake in anterior acute myocardial infarction had a significantly lower regional ejection fraction and a significantly larger thallium-201 defect score than those with 2+ positive results in chronic stage. Similarly, in inferior acute myocardial infarction, the thallium-201 defect score was significantly larger in patients with strongly positive uptake than in those with 2+ and negative uptake scores. In conclusion, strongly positive results in early technetium-99m pyrophosphate scintigraphy within 12h after the onset of acute myocardial infarction may indicate failure in limiting the infarct size by coronary thrombolysis.

Aged↗
PubMed1987

Comparison of early myocardial technetium-99m pyrophosphate uptake to early peaking of creatine kinase and creatine kinase-MB as indicators of early reperfusion in acute myocardial infarction.

The value of technetium-99m pyrophosphate (Tc-99m-PYP) scintigraphy as an indicator of reperfusion 2.8 to 8 hours after the onset of symptoms of acute myocardial infarction was compared with the value of early peak creatine kinase (CK) and CK-MB release within 16 hours after the onset of symptoms. In 29 patients who received thrombolytic therapy, recanalization was seen (group 1) and in 7 it was not (group 2). In 23 patients (79%) in group 1 scintigraphic findings were positive and in all 7 in group 2 they were negative. In 15 patients (52%) in group 1 and 1 patient (14%) in group 2, CK reached its peak level within 16 hours. In 20 patients (69%) in group 1 and 3 (43%) in group 2 the CK-MB level reached a peak within 16 hours. The sensitivity, specificity and predictive accuracy of positive results of early Tc-99m-PYP scintigraphy in predicting the reperfusion were 79%, 100% and 83%. These values are significantly higher than or similar to those of early peaking of CK and CK-MB release. In contrast to measurements of enzyme release, reperfusion data for Tc-99m-PYP scintigraphy are available immediately after thrombolytic therapy. Therefore, early Tc-99m-PYP scintigraphy (3 to 8 hours after onset of symptoms) is valuable as a noninvasive technique for early diagnosis of reperfusion.

Aged↗
PubMed1987

Clinical significance of early myocardial 99mTc-pyrophosphate uptake in patients with acute myocardial infarction.

Early 99mTc-pyrophosphate (PYP) scintigrams of 29 patients receiving coronary thrombolysis induced by urokinase, 3.9 +/- 1.2 hours after the onset of acute myocardial infarction (AMI), were evaluated. Intravenous 99mTc-PYP scintigraphy was performed 2.8 to 8.0 hours after the onset of AMI. All 19 patients with positive findings on early scintigrams had good recanalization, compared to only 3 of the 10 patients with negative findings. The seven patients with unsuccessful recanalization after coronary thrombolysis had total occlusion or subtotal occlusion with delayed washout of contrast material, and three of them had collaterals. The sensitivity, specificity, and predictive accuracy of positive results of early scintigraphy in predicting the presence of early reperfusion were 73%, 100%, and 90%, respectively. Patients with positive early scintigrams showed increasing regional ejection fraction and decreasing thallium defect scores from the acute stage to the chronic stage. These findings indicate that early 99mTc-PYP scintigraphy is a sensitive noninvasive technique for detecting early recanalization in infarcted vessels. The collateral flow or antegrade flow with delay is not enough to cause 99mTc-PYP uptake in a very early stage of AMI.

Aged↗
PubMed1985

Reversible asymmetric septal hypertrophy in acute myocarditis. Serial findings of two-dimensional echocardiogram and thallium-201 scintigram.

Serial two-dimensional echocardiographic and thallium-201 scintigraphic findings are described in a patient with acute myocarditis diagnosed by endomyocardial biopsy. On the 4th day of illness, just before the onset of congestive heart failure, the echocardiogram showed asymmetric septal hypertrophy (IVS/PW = 16 mm/10 mm = 1.6) and thallium-201 scintigram showed the ventricular septal thickening. On the 8th day of illness, when severe congestive heart failure was seen, asymmetric septal hypertrophy disappeared (IVS/PW = 8 mm/8 mm = 1.0), the left ventricle dilated markedly (LVDd = 63 mm), and the wall motion became poor (EF = 0.24). After one month, when congestive heart failure and clinical inflammatory findings disappeared, the contractility somewhat improved (EF = 0.43), although marked left ventricular dilatation remained. Thallium-201 scintigram showed some scattered persistent perfusion defects, thinning of the ventricular septal thickening, and dilatation of the left ventricle. The right ventricular endomyocardial biopsy revealed the histologic findings of the late stage of acute myocarditis. It is concluded that transient thickening of the ventricular wall may represent early changes in acute myocarditis.

Acute Disease↗
PubMed1984

Assessment of viable myocardium within infarct zone by exercise thallium-201 scintigraphy.

The viability of the myocardial regions corresponding to pathologic Q waves was evaluated. Thirty-four patients with prior myocardial infarction underwent serial thallium-201 scintigraphy during treadmill exercise testing. On the delayed images, 8 of the initial 85 segmental defects (8 patients, 9%) showed total redistribution (RD) and 11 (6 patients, 13%) showed partial RD. In contrast, 66 segments showed persistent defect. The segments with total RD were more likely to be associated with normal or hypokinetic wall motion than the segments with persistent defect (p less than 0.05). Six of the 38 segments (13%) with collateral vessels showed total RD and 10 (21%) showed partial RD. However, 35 of 38 segments (92%) without collateral vessels showed persistent defect. There was a significant difference (p = 0.02) in myocardial thallium uptake patterns when the segments with and without collateral vessels were compared. It is concluded that (1) exercise-induced thallium RD may occur in patients with prior myocardial infarction, and myocardial infarct regions with total RD are highly associated with good contractility; these suggest the presence of viable but jeopardized myocardium within the infarct zone, and (2) collateral vessels may play a role in limiting infarct size.

Adult↗
PubMed1981

Echocardiographic features of the false tendons in the left ventricle.

M mode and two dimensional echocardiographic features consistent with previously reported autopsy findings of false tendons were seen in 5 of approximately 1,000 consecutive echocardiographic examinations. Later, the presence of false tendon was proved at autopsy in one of the five cases. Examination in three cases revealed heart disease: aortic regurgitation, third degree atrioventricular (A-V) block with aortic regurgitation and invasive thymoma with pericardial effusion; examination in two cases revealed no heart disease. In three cases, M mode echocardiograms revealed in the outflow tract of the left ventricle abnormal linear echoes that strongly mimicked those in other disorders such as discrete subaortic stenosis or flail aortic valve. In two cases, there were abnormal linear echoes in the left ventricle toward the apex. In three cases, two dimensional echocardiograms revealed long-string-like echoes stretching from the upper part of the interventricular septum across the ventricular cavity to the lateral wall of the left ventricle in long and short axis views or in four chamber views. In two cases, long slender echoes between the lower parts of the interventricular septum and the left ventricle were seen in apical long axis views. These string-like echoes seem to represent the false tendons previously reported at autopsy, although actual pathologic confirmation was available in only one of the five cases. It is concluded that (1) M mode and two dimensional echocardiograms can demonstrate the presence of false tendons, (2) two dimensional echocardiograms are useful in differentiating false tendons from other conditions causing abnormal linear echoes in the outflow tract of the left ventricle on M mode echography.

Adult↗
PubMed1981

[Echocardiographic features of false tendons: with special reference to phonocardiographic significance (author's transl)].

Echocardiographic features consistent with the findings of false tendons (FTs) were described in five out of 1,000 consecutive cases, and they were studied in order to determine whether FT was responsible for the systolic murmurs. Three had heart diseases including aortic regurgitation, 3 degrees AV-block with aortic regurgitation, and pericarditis and mitral stenosis, and the remainder cases had no heart disease. M-mode echocardiograms showed abnormal linear echoes in the outflow tract of the left ventricle in three cases, and in the left ventricle toward the apex in another two cases. Two-dimensional echocardiograms revealed long string-like echoes stretching from the upper parts of the interventricular septum across the ventricular cavity to the lateral wall of the left ventricle in three cases in the long and short axis views or four chamber view. In another two cases, there were long slender echoes binding the lower parts of the interventricular septum and the left ventricle in the apical view. These string-like echoes seemed to represent FTs reported previously in autopsy cases. Phonocardiography with pharmacological study (amyl nitrite and methoxamine) showed no significant systolic murmur, for which Fts had been considered to be responsible, even in a dilated left ventricle. We conclude that (1) M-mode and two-dimensional echocardiograms can demonstrate the presence of FTs, (2) two-dimensional echocardiograms might be utilized in differentiating FTs from other abnormal linear echoes in the outflow tract of the left ventricle seen in M-mode echograms, and (3) FTs do not necessarily cause systolic murmur.

Adult↗
PubMed1979

The effect of diltiazem hydrochloride upon sodium diuresis and renal function in chronic congestive heart failure.

d-3-Acetoxy-cis-2,3-dihydro-5-]2-(dimethylamino)ethyl]-2-(p-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one hydrochloride (diltiazem HCl) was orally administered to 9 patients with chronic congestive heart failure (Class IIb to III, NYHA) to examine whether the drug induces sodium retention and aggravates congestive heart failure. Renal hemodynamics and urinary electrolytes excretion were measured for 3 h after the medication in 6 out of 9 patients. Four of the rest of patients had received chronic administration of the drug for about 2 weeks. There was a significant increase in urinary sodium excretion without noticeable change in renal hemodynamics after diltiazem administration, demonstrating the presence of its direct inhibitory action on renal tubules. The increase in urinary sodium excretion was more marked in patients with heart failure than in those without. This difference in the response to diltiazem may be due to the functional constriction of renal cortical vessels in heart failure. This constriction may be related to renin-angiotensin system which diltiazem was reported to antagonize. The chronic administration of the drug did not induce sodium retention and edema. There was no deterioration of symptoms due to congestive heart failure such as dyspnea and body weight increase. It may be concluded that diltiazem does not aggravate congestive heart failure through its diuretic action and probably its systemic vasodilating action.

Adult↗
PubMed1978

Effects of diltiazem hydrochloride on renal hemodynamics and urinary electrolyte excretion.

Dilitazem hydrochrolide, a potent coronary dilator, was administered in 18 patients to evaluate its effect on renal hemodynamics and urinary electrolyte excretion. Renal blood flow (RBF), glomerular filtration rate (GFR), and cardiac output were determined in 8 ambulatory patients by means of external counting of radioisotope dilution before and 3 or 4 weeks after the medication. Althoug RBF tended to increase after the therapy, there was no statistically significant change in RBF, GFR and cardiac output. Renal fraction of cardiac output (RBF/CO) showed a significant increase by 29.5% after the therapy, indicating that the renal vascular resistance decreased to a greater extent than the extrarenal vascular resistance. Standard renal clearance was performed in 10 inpatients whom 60 mg of dilitiazem was administered orally. Renal plasma flow (RPF) showed an average increase by 15% 3 hr after the administration of the drug, which was not, however, statistically significant. There was no certain trend for GFR and filtration fraction. Urinary sodium excretion (UNaV) began to increase one hr and reached its peak 2 hr after the medication in 9 out of the 10 patients. It may be concluded that diltiazem has a direct inhibitory action against the renal tubular reabsortion of sodium, although the participation of renal hemodynamics can not be denied.

Adult↗