Search PubMed⌕ Search

Biomedical subjects

T Uraoka

Publications and source records attributed to T Uraoka.

At least 37 records · Page 2Linked to original sources

[Absence of induced spasm by intracoronary injection of 50 micrograms acetylcholine in the right coronary artery: usefulness of 80 micrograms of acetylcholine as a spasm provocation test].

This study investigated whether the maximal dose of 50 micrograms acetylcholine for the induction of coronary spasm in the right coronary artery is adequate. The acetylcholine test was performed in 388 consecutive patients to evaluate spasm from January 1994 to December 1997. Coronary spasm in the right coronary artery was induced in 43 patients, 37 men and 6 women with a mean age of 63 +/- 8 years by intracoronary injection of 80 micrograms of acetylcholine rather than 50 micrograms. These included 15 patients (35%) with rest angina, 23 patients with ischemic heart disease other than rest angina and 5 patients (12%) with non-ischemic heart disease. Acetylcholine was injected in incremental doses of 20, 50 and 80 micrograms into the right coronary artery. Positive spasm was defined as induction of more than 90% reversible narrowing associated with either usual chest pain or ischemic electrocardiographic changes. Clinical and angiographical characteristics was studied in these patients. Fifteen (35%) patients had rest angina and 4 patients had variant angina with ST elevation in the inferior leads. Two thirds of the patients had coronary spasm in the distal portion of the right coronary artery and one third of those disclosed spasm focally. Coronary spasm was induced in 38 (15%) of 246 patients with ischemic heart disease and in 5 (4%) of 142 patients with non-ischemic heart disease. The prevalence of positive spasm in patients with ischemic heart disease was significantly higher (p < 0.01) than in patients with non-ischemic heart disease. A dose of 80 micrograms of acetylcholine, more than the maximal standard dose, might be clinically useful for the induction of spasm in the right coronary artery if coronary spasm of this artery is strongly suspected.

Acetylcholine↗

[Is coronary spasmodicity unchangeable?: a study with acetylcholine or ergonovine in patients with ischemic heart disease].

Fluctuations of spasmodicity have been reported in affected vessels in patients with vasospastic angina, but the incidence of spasmodicity induced by pharmacologic agents on both vessels with spasm and vessels without induced spasm has not been investigated. Repeated spasm provocation tests by acetylcholine or ergonovine were performed at 13.1 +/- 9.9 month intervals (3-50 months) in 111 vessels of 50 patients with ischemic heart disease, consisting of 19 old myocardial infarction and 31 angina pectoris, who did not undergo angioplasty or have signs of advancing atherosclerosis. Spasm was defined as present when more than 90 percent stenosis was accompanied by the appearance of usual chest pain or significant electrocardiographic changes. Ninety-six vessels (86.5%), 65 without spasm and 31 with spasm, revealed coincident responses and the remaining 15 vessels contrary reacted. The coincidence rate of spasmodicity in patients at intervals of within 24 months (90.2%) was significantly higher (p < 0.05) than that at intervals of over 24 months apart (70.4%). The spasm coincidence rate was 67.3% in the vessels with provoked spasm by either the first or second tests. Only one (0.9%) out of the 111 vessels showed obvious progressive atherosclerosis during this study. The majority of vessels showed identical spasmodicity within 2 years. In conclusion, coronary spasmodicity might remain unchanged for at least 2 years despite medication with calcium channel blockers and isosorbide dinitrate.

Acetylcholine↗

Changes in coagulation and fibrinolytic system after local intra-arterial thrombolysis for acute ischemic stroke.

Intracerebral hemorrhagic transformation is one of the most important complications of thrombolytic therapy for acute ischemic stroke. The relationship between changes in markers for the coagulation and fibrinolytic systems and occurrence of hemorrhagic transformation was determined after local intra-arterial thrombolytic therapy using urokinase (UK) (24 patients) or recombinant tissue plasminogen activator (t-PA) (10 patients) within 6 hours of onset. All 34 patients had no hypodensity areas on initial computed tomography scans. Plasma concentrations of fibrinogen-fibrin degradation products (FDP), fibrinogen, alpha 2-plasmin inhibitor (alpha 2-PI), plasmin-alpha 2 plasmin inhibitor complex (PIC), thrombin-antithrombin III complex (TAT), and D-dimer were measured. Hemorrhagic transformation occurred in seven patients (21%) with complete or partial recanalization; four in the UK group and three in the t-PA group. Doses of the thrombolytic agents did not correlate with the incidence of hemorrhagic transformation. The FDP levels in the hemorrhagic transformation group treated with UK significantly increased immediately and 1 hour after the therapy. The alpha 2-PI activities decreased and PIC levels increased in both the hemorrhagic transformation and the nonhemorrhagic groups after the therapy. The TAT levels in both groups tended to be higher than the normal range, but there was no significant difference from the pretreatment levels. The D-dimer levels in the hemorrhagic transformation group were higher than those in the nonhemorrhagic group at 24 hours after the therapy. Furthermore, the D-dimer levels were significantly higher in patients with complete recanalization compared with those with none or partial recanalization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Evaluation of risk of hemorrhagic transformation in local intra-arterial thrombolysis in acute ischemic stroke by initial SPECT.

BACKGROUND AND PURPOSE: Thrombolytic therapy was carried out on patients with acute ischemic stroke, and the risk of hemorrhagic transformation was evaluated from the residual cerebral blood flow (CBF) by pretherapeutic single-photon emission-computed tomography (SPECT). METHODS: Local intra-arterial thrombolytic therapy was carried out using urokinase or recombinant tissue plasminogen activator (rt-PA) within 6 hours from the onset in 34 patients in whom no hypodensity areas were observed on the initial computed tomography examination. In the 20 patients with carotid territory occlusion who underwent 99mTc-labeled hexamethylpropyleneamine oxime (99mTc-HMPAO) SPECT, the residual CBF of the ischemic region was evaluated semiquantitatively by calculating two parameters: the ischemic regional activity to cerebellar activity ratio (R/CE ratio) and asymmetry index (AI). RESULTS: The occluded vessels could be recanalized in 22 (92%) of the 24 patients in the urokinase group and in all 10 of the patients in the rt-PA group. Hemorrhagic transformation appeared in 4 patients in the urokinase group and 3 patients in the rt-PA group. Among the 20 patients who underwent SPECT before the treatment, the residual CBF was lower in the 5 patients who developed hemorrhagic transformation than in the 15 who did not (P < .05). Hemorrhagic transformation occurred in all patients with R/CE ratio of less than 0.35 and AI of more than 1.5. CONCLUSIONS: The risk of hemorrhagic transformation after recanalization of occluded vessels by local intra-arterial thrombolytic therapy was considered to be high when the pretherapeutic residual CBF was markedly reduced.

Acute Disease↗

Membranous glomerulonephritis associated with enterococcal endocarditis.

An autopsy case of membranous glomerulonephritis associated with enterococcal endocarditis was reported. Although enterococcal antigen was not identified in glomerular deposits, the eluate from the patient's renal tissue was shown to specifically recombine with cells of the enterococcus isolated from his own ante mortem blood. Hypocomplementemia, circulating immune complexes and antienterococcal antibodies were also observed. These findings suggest that enterococcus-related immune complexes played a role in the pathogenesis of glomerulonephritis associated with enterococcal endocarditis in this patient.

Aged↗

Effect of dilazep on hemoglobin-oxygen affinity in patients with ischemic heart disease.

The effects of orally administered dilazep, an antianginal drug, on the hemoglobin-oxygen affinity were studied in 31 cases with ischemic heart disease. Prior to medication, the mean P50 value was 29.2 +/- 1.65 mmHg. There were no significant differences in the P50 value according to the age of patient or the severity of the coronary arterial disease. Acute effects of dilazep were studied in 29 patients. The 30 min and 60 min post-administration P50 values increased significantly to 30.2 +/- 2.55 mmHg and 30.4 +/- 2.31 mmHg, respectively. Eight patients were administered 300 mg of oral dilazep daily for 4 weeks. Three of 4 in whom exercise tolerance improved showed increases in P50. No changes in various factors which might affect the P50 value, including 2,3-DPG, were found.

2,3-Diphosphoglycerate↗

[Usefulness of ECG gated cardiac computed tomography in measurement of left ventricular volume and wall thickness].

Electrocardiogram gated cardiac computed tomography (CT) was performed to evaluate the usefulness in the measurement of left ventricular volume and left ventricular wall thickness in 25 patients; five with angina pectoris, five with old myocardial infarction, eight with hypertrophic cardiomyopathy, four with dilated cardiomyopathy, and three healthy men. The left ventricular volume was calculated as the sum of the volume of each slice, which was area times thickness of the slice. The left ventricular wall thickness was measured in reconstructed short-axis view at the level of the mitral valve and papillary muscle. The left ventricular volume and left ventricular wall thickness determined by CT were compared with that by left ventriculography (LVG), and that by two-dimensional echocardiography (2 DE), respectively. The following results were obtained. There were good relationships between left ventricular volume, end-diastolic volume, end-systolic volume, ejection fraction by CT and those by LVG, but left ventricular volume by CT was smaller by about 20% than that by LVG. In the measurement of stroke volume, no relationship was recognized between CT and LVG. Concerning the measurement of left ventricular wall thickness, more available figures were obtained by CT than by 2 DE, particularly at the apical region, lateral wall, and posterior wall. In the other segments of the left ventricle, CT was also more suitable for the measurement of the wall thickness. Interventricular septal thickness was correlated between reconstructed short-axis view of CT (Y) and transverse view of CT (X), and the equations Y = 0.66X + 2.13 (r = 0.79) at the mitral valve level, and Y = 0.56X + 3.00 (r = 0.81) at the papillary muscle level were obtained. Therefore, reconstructed short-axis view should be used for the measurement of the left ventricular wall thickness not to overestimate the thickness.

Angina Pectoris↗

[Two cases with the heart murmur originated from aortocoronary bypass: the diagnostic use of dipyridamole (author's transl)].

Two cases with the heart murmurs considered to be caused by aortocoronary (A-C) bypass surgery were reported. Case 1: A systolic and an early and late diastolic murmurs were noted following A-C bypass surgery. The murmurs were located at the second left intercostal space. After methoxamine, the systolic and early diastolic murmurs increases slightly in intensity, while the late diastolic murmur did not change. Amyl nitrite inhalation slightly increased the intensity of the systolic murmur, but did not that of the diastolic murmur. Dipyridamole injection at a rate of 0.142 mg/kg/min resulted in the increase of both systolic and diastolic murmurs. Case 2: A diastolic murmur was noted following the bypass surgery, which was situated over the fourth left intercostal space, 4 cm outside from the left sternal border. Methoxamine injection intensified the murmur. The murmur was not affected by amyl nitrite. After dipyridamole injection, the murmur was slightly intensified. Dipyridamole is known to dilate coronary vessels without affecting appreciably the systemic circulation. In these two cases, the murmur noted following A-C bypass surgery was increased with dipyridamole, suggesting clinical applicability of this drug in ascertaining the bypass flow murmur.

Coronary Artery Bypass↗

[Relationship between vascular diameter and intracardiac pressure in tricuspid or pulmonary insufficiency detected by contrast echocardiography (author's transl)].

In order to evaluate the usefulness of contrast echocardiography in the diagnosis of tricuspid (TI) and pulmonary insufficiency (PI), 30 patients with various heart diseases and 7 controls were examined. The dimensions of the inferior vena cava and pulmonary artery were also measured on the two-dimensional echocardiogram. Cardiac catheterization was performed in 18 patients to study the relationship between the diameters of the vessels and the intracardiac pressures. The following results were obtained. 1) TI was detected without difficulty by contrast method using two-dimensional echocardiography on the four-chamber view. The diagnostic sensitivity was higher than that of conventional methods. 2) PI was also detected by the parasternal approach. The regurgitation of the contrast material across the pulmonary valve was easily confirmed because of pulmonary arterial dilatation. 3) In the cases with TI, the dimension of the inferior vena cava was larger than 20 mm. The right ventricular systolic pressure and the mean right atrial pressure were higher than 40 mmHg and 6 mmHg, respectively.

Blood Pressure↗

Changes of cardiac performance in renal failure.

Clinical and experimental studies were carried out in order to evaluate the role of myocardial dysfunction in the genesis of circulatory congestion associated with renal failure. Among the patients with chronic renal failure, those with circulatory congestion had greater blood volume and higher venous pressure while lower cardiac index and stroke work index than those without circulatory congestion. After peritoneal dialysis, although blood volume and venous pressure decreased in both groups, cardiac index increased in the former while it decreased in the latter group. In 15 dogs, acute renal failure was produced by ligating both ureters. As uremia developed, blood volume and left ventricular end-diastolic pressure increased with or without an increase in cardiac index. The depression of ventricular function curve was evident in all the dogs. The peritoneal dialysis performed at this stage resulted in a prompt recovery of left ventricular end-diastolic pressure with minimum change in cardiac index. The measurement of dp/dt/IIT also indicated a depression of myocardial contractility at uremic stage and its recovery after dialysis. We conclude that impairment of myocardial function is implicated in the development of circulatory congestion in renal failure.

Acute Kidney Injury↗