Search Results
Results 401 - 450 of 715
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Simons M - - 1994
BACKGROUND: The availability of clinical information often influences the interpretation of diagnostic imaging information. METHODS AND RESULTS: In this study we examined the impact of such data on interpretation of exercise thallium scans and the differences in analysis of such information between radiologists and clinicians. Two hundred thirty-seven exercise tolerance ...
Marangelli V - - 1994
OBJECTIVES: This study assessed and compared the diagnostic potential of exercise, transesophageal atrial pacing and dipyridamole stress echocardiography in a clinical setting. BACKGROUND: Although they have been widely studied, no data exist with regard to comparisons of these procedures in a head-to-head study in different clinical settings. METHODS: One hundred ...
Arora G D - - 1994
To determine the influence of tobacco abuse on thallium 201 lung uptake during exercise, we examined 185 consecutive subjects with normal myocardial perfusion scans and without electrocardiographic evidence of left ventricular hypertrophy. The subjects were divided into two groups: group 1 subjects (n = 60) had histories of smoking and ...
Nap A M - - 1994
Thyroidal 99mTcO4- (pertechnetate) uptake percentages were determined in unanesthetized euthyroid (n = 13) and hyperthyroid (n = 18) cats. Maximal uptakes were observed 60 minutes after IV injection of the radionuclide and ranged from 0.3 to 3.9% of the dose in euthyroid cats (median 2.23%) and from 5.2% to 23.9% ...
Marwick T H - - 1994
OBJECTIVE: To compare the ability of dobutamine and exercise stress to induce myocardial ischaemia and perfusion heterogeneity under routine clinical circumstances. DESIGN: 86 active patients without previous myocardial infarction were studied by dobutamine and exercise stress protocols and coronary angiography. During both tests patients underwent electrocardiography, digitised echocardiography, and perfusion ...
Denvir M A - - 1994
A detailed comparison of stress thallium images utilizing exercise (symptom-limited bicycle ergonometer) and adenosine (infused at 50 micrograms kg-1 min-1 increasing by 25 micrograms kg-1 min-1 every 2 min to a maximum tolerated dose) was performed in 20 patients with angiographically documented coronary disease. Ten patients were receiving beta-blockade at ...
Minoda K - - 1994
Exercise and hyperventilation tests are often used as the provocative tests for coronary artery spasm. To examine the distribution of myocardial blood flow during exercise-induced and hyperventilation-induced attacks of coronary spasm, thallium-201 myocardial scintigraphy was performed in 47 patients with variant angina. The extent and severity scores and severity index ...
Grover-McKay M - - 1994
In patients who cannot perform treadmill exercise, both intravenous dipyridamole and arm exercise have been used with thallium-201 scintigraphy to detect significant coronary artery disease. However, no study has directly evaluated the results of intravenous dipyridamole and arm exercise thallium scintigraphy as compared with coronary angiography. It was the purpose ...
Sakata K - - 1994
This study was performed to assess the value of washout rate analysis of quantitative exercise thallium-201 emission computed tomography in vasospastic angina patients without significant coronary stenosis. Quantitative analysis of both thallium-201 perfusion and washout rate before and after drug treatment was performed in 48 patients with vasospastic angina and ...
Walamies M - - 1994
Myocardial metabolism in exercise was determined by studying 21 syndrome X patients and 14 healthy volunteers with an aromatic fatty acid analogue IPPA and a gamma camera. We developed criteria for visual semiquantitative assessment of relative segmental radiotracer uptake and washout, and tested a new computer program for quantitative evaluation. ...
Hoffmann R - - 1994
Non-invasive documentation of restenosis after successful percutaneous transluminal coronary angioplasty (PTCA) remains a problem. Thus, transoesophageal pacing echocardiography (TPE) with simultaneous rapid atrial pacing via the same probe, a recently validated method for detection of coronary artery disease, was used in 60 patients for detection of restenosis after successful PTCA ...
Grip L - - 1994
Eighteen patients with stable exertional angina pectoris were investigated by thallium-201 (201Tl) exercise and redistribution single photon emission computed tomography (SPECT) after coronary angiography. Eight of the patients had a previous myocardial infarct. Six patients had single-, eight double- and four triple-vessel disease. An exercise SPECT was acquired 10 min ...
Takeishi Y - - 1994
Thallium-201 (Tl-201) distribution during adenosine infusion was assessed quantitatively and compared with that of exercise imaging. Adenosine and exercise Tl-201 single-photon emission computed tomography (SPECT) were performed in 40 patients with suspected coronary artery disease. In the whole-body images (n = 5) and the unprocessed anterior projection images acquired as ...
Wackers F J - - 1994
The role of physical exercise in myocardial perfusion imaging is critical for two reasons: (1) stress is essential to create heterogeneity of blood flow in myocardial regions supplied by normal versus stenosed coronary arteries and (2) exercise data provide invaluable information that can influence the interpretation of perfusion images. Image ...
Leppo J A - - 1994
Dipyridamole is a pharmacologic stressor used in place of exercise for myocardial perfusion imaging in patients who cannot exercise due to various physical limitations. Perfusion studies with dipyridamole can identify coronary artery disease (CAD) as accurately as maximal exercise stress testing. In addition, dipyridamole myocardial perfusion studies are useful to ...
Dovgan D J - - 1994
The purpose of this study is to determine the range of maximal diaphragmatic crural thickness during different phases of respiration and to correlate crural thickness with age and gender. Prospective evaluation of computed tomographic (CT) scans of 200 patients without juxtacrural abnormalities was performed. Maximal short-axis crural thickness measurements were ...
Lette J - - 1994
Exercise myocardial perfusion imaging with Tc-99m sestaMIBI is routinely used to detect underlying coronary stenoses. Ischemia is diagnosed in regions that display decreased tracer uptake during exercise as compared to rest. Tc-99m sestaMIBI SPECT images of 42 healthy volunteers were assessed both qualitatively (tomographic slices) and quantitatively (sectored polar map) ...
Verani M S - - 1994
Dobutamine, a pharmacologic stressor, is useful for myocardial perfusion imaging in patients who cannot exercise. Patients with asthma or severe chronic obstructive pulmonary disease who are at risk for adverse effects from either dipyridamole or adenosine are prime candidates for dobutamine perfusion studies. Dobutamine is a predominant beta-1 agonist that ...
Lee J - - 1994
There are currently four common types of stress used with thallium-201 imaging in the diagnosis of coronary artery disease and risk assessment. The objective of this study was to examine the thallium biokinetics during exercise, adenosine, dipyridamole and dobutamine stress testing in 15 healthy volunteers. METHODS: Each subject underwent planar ...
Gimple L W - - 1994
The use of physiologic testing for prognostication continues to be useful and widely applied in the predischarge evaluation of patients recovering from an uncomplicated acute myocardial infarction in the thrombolytic era. Because patients with abnormal exercise test results are now routinely sent for angiography, there are no randomized trials or ...
Pennell D J - - 1994
There are a number of stress techniques in common use for 201Tl myocardial imaging but few studies have been performed comparing the biodistribution of 201Tl in each case. METHODS: We studied 36 normal patients after six different stress regimens by whole-body imaging, 40 min after 201Tl injection. The stress regimens ...
Iskandrian A S - - 1994
BACKGROUND: This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD). METHODS AND RESULTS: The treadmill exercise score was derived from exercise duration, degree of ST segment depression, and the ...
al-Tikriti M S - - 1994
The regional brain distribution and pharmacological specificity of three high affinity tracers for the dopamine (DA) D2 receptor: [123I]IBF, [123I]epidepride, and [123I]2'-ISP were assessed by SPECT imaging of non-human primates. The ratios of striatal-to-occipital activities at the time of peak striatal uptake were 2.2, 6.3 and 1.7, respectively. From the ...
Weindling S N - - 1994
OBJECTIVES: This study was conducted to determine the prevalence of myocardial perfusion abnormalities at rest and exercise and to assess exercise capacity in children after the arterial switch operation. BACKGROUND: There have been sporadic reports of myocardial ischemia or sudden death in children after the arterial switch operation for transposition ...
Tawarahara K - - 1994
To assess the clinical value of simultaneous dual myocardial imaging with iodine-123-beta-methyl-iodophenyl-pentadecanoic acid (123I-BMIPP) and thallium-201 (201Tl), myocardial imaging was performed at rest and during exercise in seven patients with coronary heart disease. When 123I-BMIPP and 201Tl images were compared, the initial exercise and resting images agreed 87% and 64%, ...
Herman S D - - 1994
Studies using dobutamine thallium-201 myocardial perfusion imaging have suggested a high sensitivity and specificity for the detection of coronary artery disease. However, few data are available comparing dobutamine with exercise stress for the detection and localization of perfusion defects. This study compared the effects of dobutamine and exercise stress using ...
Miletich R S - - 1994
Regional cerebral perfusion was assessed in six patients with asymmetric Parkinson's disease (PD) of mild to moderate severity and in six matched normal subjects using 99mTc-bicisate single photon emission computed tomography (SPECT). Regional activity was normalized to whole-brain activity. Each subject was studied twice, separated by 15.2 +/- 9.2 and ...
Barasch E - - 1994
Stress echocardiography has been developed in recent years as an effective noninvasive test for the detection and assessment of coronary artery disease. This method combines exercise with 2-dimensional echocardiography, which can assess regional and global left ventricular function during stress. Dobutamine infusion, a pharmacologic means of producing cardiovascular stress, appears ...
Santos-Ocampo C D - - 1994
BACKGROUND: Pharmacologic stress has been shown in animal studies to induce high degrees of myocardial hyperemia. At these levels of myocardial blood flow, the myocardial uptake of technetium 99m sestamibi may plateau and may affect the diagnostic accuracy. This study compared the effects of myocardial hyperemia induced by exercise, dipyridamole, ...
Yamagami H - - 1994
To test the clinical significance of technetium-99m teboroxime regional myocardial clearance in the detection of coronary artery disease, 25 patients underwent dynamic planar or single-photon emission tomographic (SPET) myocardial imaging with 99mTc-teboroxime after exercise and again 2 h later at rest. All patients underwent both thallium-201 exercise and redistribution SPET ...
Casanova R - - 1994
Restenosis remains the main limitation of percutaneous transluminal coronary angioplasty (PTCA). Since it seems likely that restenosis not severe enough to induce ischemia may be better detected with pharmacological testing than with exercise, we investigated whether dipyridamole thallium scintigraphy is better than exercise-electrocardiogram and exercise-thallium in predicting restenosis after PTCA. ...
Yoshioka H - - 1994
We evaluated the acute changes in exercised muscle using magnetization transfer contrast (MTC) MR imaging with a short repetition time sequence. Ten volunteers performed supine ankle dorsiflexion exercise. MTC gradient-recalled echo (GRE) images were obtained before and after exercise at 1.5 T. The effect of MTC was assessed by dividing ...
Ignaszewski A P - - 1993
Dipyridamole-induced coronary hyperemia with 201Tl myocardial perfusion scintigraphy can detect ischemic regions in individuals unable to perform adequate exercise, but it has several limitations. Symptom-limited exercise supplementation to intravenous dipyridamole can potentially overcome them, but the safety and diagnostic accuracy for this combination has not been established. Between 1987 and ...
Abe S - - 1993
To determine the clinical usefulness of adenosine Tl-201 imaging for the evaluation of coronary artery disease, 22 patients with suspected coronary artery disease who underwent adenosine and exercise Tl-201 single photon emission computed tomography (SPECT) were studied. The peak levels of heart rate (83 vs 123 bpm, p < 0.001), ...
Rivitz S M - - 1993
Myocardial perfusion imaging with thallium-201 has been used extensively for many years in the evaluation of ischemic heart disease. It is a valuable adjunct to exercise treadmill testing and is especially helpful in evaluating cardiac perfusion in patients who have abnormal resting electrocardiograms, who are unable to exercise, and whose ...
Sridhara B S - - 1993
Technetium-99m (Tc-99m) tetrofosmin, a new myocardial perfusion imaging agent, was evaluated at exercise and rest in 50 patients with documented coronary artery disease to determine myocardial kinetics, redistribution and ideal imaging time. Planar imaging was performed at 5, 30, 60, 90, 120 and 240 minutes after an injection of Tc-99m ...
Bisi G - - 1993
The aim of this study was to compare the reliability of 99Tcm-sestamibi myocardial scintigraphy for the assessment of coronary artery disease extent using two different stresses (exercise and dipyridamole) and imaging techniques (planar versus single photon emission tomography, SPET) in a patient population of 20 subjects, all also studied with ...
Pennell D J - - 1993
Exercise thallium imaging is effective and provides information on exercise tolerance and symptoms, but is less sensitive if exercise is submaximal. When dipyridamole alone is used for such patients, the exercise parameters are lost and high background uptake results. This study examines dipyridamole combined with maximal exercise, to capitalize on ...
Previtali M - - 1993
To compare the value of dobutamine and dipyridamole stress echocardiography with exercise stress testing for the diagnosis of coronary artery disease (CAD), 80 patients with chest pain of suspected myocardial ischemic origin (57 with CAD and 23 without significant CAD) underwent dobutamine stress echocardiography (5 to 40 micrograms/kg/min), dipyridamole echocardiography ...
Kujacic V G - - 1993
Dynamic exercise echocardiography is sensitive and specific in detection and evaluation of coronary artery disease. Frequently, however, patients cannot achieve maximum exercise because of various factors. The aims of this study were to compare usefulness of adenosine infusion and dynamic exercise to induce myocardial ischemia detected with 2-D echocardiography and ...
Hoffmann R - - 1993
In 66 patients with suspected coronary artery disease (CAD), exercise electrocardiography (ECG), exercise echocardiography, dobutamine stress echocardiography (dosage, 5 to 40 micrograms/kg/min), single-photon emission computed tomography (SPECT) using methoxy-isobutyl-isonitrile (MIBI) and coronary angiography were performed prospectively to compare methods for detecting CAD. CAD was defined as 70% luminal area stenosis ...
Marie P Y - - 1993
The usefulness of exercise single photon emission computed tomography (SPECT)-thallium for detecting asymptomatic restenosis was assessed prospectively in 62 patients with angina before angioplasty, who underwent < or = 6-month re-angiography and exercise SPECT-thallium imaging. Among patients with restenosis, nine had recurrence of angina but eight did not. These two ...
Ciniglio R - - 1993
Abnormal wall motion detected with exercise echocardiography identifies ischemic myocardium, while normal myocardium exhibits hyperkinetic motion. The normal, hyperkinetic response to exercise is transient and is predictive of an excellent prognosis. However, there are few data on the duration of the hyperkinesis after peak exercise. Our purpose was to determine ...
Cyran S E - - 1993
The combination of two-dimensional and continuous-wave (CW) Doppler echocardiographic imaging forms the cornerstone of diagnostic imaging in pre- or postoperative coarctation of the aorta. Because of the frequent association of other congenital heart defects, e.g., bicuspid aortic valve, a segmental imaging approach with multiple image planes should be used. CW ...
Walamies M - - 1993
The diagnostic value of 123I-phenylpentadecanoic acid (IPPA) metabolic cardiac imaging was studied in a group (n = 29) of patients with angiographically confirmed CAD using single photon emission computed tomography (SPECT). A symptom-limited exercise test was first done with IPPA, and 2 days later with thallium. Medications were not withheld ...
Munck O - - 1993
A slow washout of 201Thallium has a high diagnostic and prognostic value for coronary artery disease. The aim of the present work was to contribute with reference data on 201Tl uptake and washout from the myocardium. With a quantitative method using circumferential profiles and interpolative background subtraction we performed 201Tl ...
Nisen H O - - 1993
The aim of this study was to find out the normal response of the duplex Doppler (DD) parameter resistance index (RI) during a high dose prostaglandin E1 (40 micrograms) induced erection and to evaluate the clinical usefulness of DD scanning in the diagnosis of cavernovenous leakage (CVL). The results of ...
Segall G M - - 1993
Twenty-six patients underwent conventional exercise/4-h redistribution thallium myocardial perfusion imaging as well as rest/exercise imaging on different days. For the rest/exercise study, patients were imaged 10 min after receiving 1 mCi thallium at rest. The resting study was immediately followed by symptom-limited treadmill exercise. Patients were injected with 2 mCi ...
Lee J - - 1993
The myocardial thallium concentration is different during pharmacologic than exercise stress testing due to differences in coronary blood flow and cardiac output. These differences may affect the quantitative measurement of the size of ischemic myocardium if a stress-specific normal file is not used. This study examined this concept in 34 ...
Pirelli S - - 1993
The usefulness of high-dose (< or = 0.84 mg/kg over 10 minutes) dipyridamole echocardiography testing was compared with that of exercise thallium-201 scintigraphy in detecting restenosis (> 70% lumen reduction) in 50 asymptomatic patients with ST-segment depression during maximal exercise testing 3 months after successful coronary angioplasty. Dipyridamole echocardiography testing ...
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