Search Results
Results 351 - 400 of 742
< 3 4 5 6 7 8 9 10 11 12 13 >
Blumenthal R S - - 1996
BACKGROUND: Exercise testing, even when combined with radionuclide perfusion imaging, does not accurately predict future clinical coronary heart disease (CHD) in low-risk asymptomatic populations. We hypothesized that these tests would perform better in a higher-risk population with a high prevalence of occult CHD. Siblings of persons with premature CHD represent ...
Golub R J - - 1996
BACKGROUND: To evaluate the effectiveness of published nuclear cardiology training guidelines, the diagnostic accuracy of image interpretation by nuclear cardiology trainees was compared with that of experienced nuclear cardiologists. METHODS AND RESULTS: The accuracy of three experienced nuclear cardiologists and three trainees with level II experience following Society of Nuclear ...
Thompson E J - - 1996
Pharmacologic induction of exercise with dobutamine hydrochloride, coupled with the technology of echocardiography, is an alternate method for evaluating ischemic heart disease. Dobutamine stress echocardiography involves obtaining echocardiographic images before, during, and after a titrated dobutamine infusion is administered. The study is positive if global or regional ventricular wall motion ...
Matsunari I - - 1996
Defect size on exercise-rest technetium (Tc)-99m tetrofosmin myocardial perfusion imaging was compared with that on exercise-reinjection thallium-201 imaging with 20 patients with 1-vessel coronary artery disease. In each patient, exercise-reinjection thallium-201 single-photon emission computed tomography (SPECT) and exercise-rest Tc-99m tetrofosmin SPECT imaging were performed. For visual analysis of the obtained ...
Beauregard L A - - 1996
Signal averaging can be used to assess changes in myocardial activation under a variety of physiological conditions including stress. This study prospectively evaluated patients who underwent rest and exercise recording of signal-averaged electrocardiograms. The 163 patients were divided into three groups based on thallium results: normal (group I), reperfusion (group ...
Cramer M J - - 1996
Intravenously administered adenosine and high-dose dipyridamole, both combined with low-level exercise stress, were compared in a head-to-head fashion using 99Tcm-methoxyisobutyl isonitrile (99Tcm-MIBI) single photo emission tomography (SPET) myocardial perfusion imaging. Thirty-nine consecutive patients who had undergone coronary arteriography underwent 99Tcm-MIBI (740 Mbq) SPET after dipyridamole (0.84 mg kg-1) and after ...
van Eck-Smit B L - - 1996
As several reinjection procedures have shown encouraging results in terms of imaging, we investigated whether the kinetics of thallium-201 would differ between the standard stress-redistribution-reinjection approach and the stress-immediate reinjection approach. In 53 consecutive patients with undiagnosed chest pain, 75 MBq (2 mCi) 201Tl was injected at maximal exercise. In ...
Dimitrow P P - - 1996
The aim of this study was to evaluate the relation of coronary flow velocity (CFV) and coronary flow reserve (CFR) to exercise capacity in ten verapamil-treated patients with hypertrophic cardiomyopathy (HC). Using Doppler transesophageal echocardiography, we assessed diastolic CFV in the proximal left anterior descending coronary artery at baseline and ...
Kisacik H L - - 1996
The object of our study was to compare the value of exercise stress testing with simultaneous dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computed tomography for the diagnosis of coronary artery disease. Sixty-nine patients with either suspected or proven coronary artery disease underwent simultaneous dobutamine technetium-99m isonitrile single-photon emission ...
Roig E - - 1996
BACKGROUND: Previous studies have suggested that aminophylline improves exercise-induced ischaemia by preventing the redistribution of the coronary flow from ischaemic to non-ischaemic myocardium. The purpose of the study was to assess whether aminophylline improves myocardial perfusion in zones supplied by collateral circulation. METHODS: Twenty-three patients with an occluded coronary artery ...
Schroeder-Tanka J M - - 1996
The aim of this study was to assess the relationship between the exercise electrocardiogram (ECG) and late thallium-201 (201Tl) reversibility in a series of 72 consecutive patients with undiagnosed chest pain and an initial persistent perfusion defect on conventional stress/4-h redistribution imaging. We wished to establish the diagnostic accuracy of ...
Tawa C B - - 1996
This study was undertaken to evaluate whether adenosine echocardiography is comparable to exercise echocardiography in the detection of ischemia in patients with suspected coronary artery disease and to assess whether the addition of handgrip exercise to adenosine enhances the induction of ischemia in these patients. Accordingly, 67 patients with suspected ...
Votaw J R - - 1996
It has become commonplace to compare scanner sensitivity characteristics by comparing noise equivalent count rate curves. However, because a 20-cm diameter uniform phantom is drastically different from a human brain, these curves give misleading information when planning a neuro activation PET experiment. Signal-to-noise ratio (SNR) calculations have been performed using ...
- - 1996
To describe the various types of stress tests and to provide guidelines for selecting a specific test for an individual patient. Myocardial perfusion imaging, radionuclide angiography, stress echocardiography, and cardiopulmonary exercise testing are described. The advantages and limitations of these techniques are reviewed and compared with those of standard treadmill ...
Hoffmann R - - 1995
The purpose of this prospective study was to examine the incidence of exercise-induced ischaemia before and after angioplasty as well as 4 months later by exercise echocardiography, to evaluate the prognostic value of exercise echocardiography performed after angioplasty as regards the development of restenosis and to determine whether serial exercise ...
Armstrong W F - - 1995
Arbutamine (Gensia, Inc., San Diego, CA) is a newly-developed sympathomimetic agent specifically designed for cardiovascular stress testing. It has been successfully used for the detection of coronary artery disease in conjunction with electrocardiography, echocardiographic and radionuclide techniques. Arbutamine increases heart rate and contractility, thus provoking ischaemia in a manner analogous ...
Ali S M - - 1995
We determined the intra, inter-observer and temporal variability of upright bicycle exercise echocardiography in 50 consecutive patients with suspected coronary heart disease. Using significant artery stenoses as reference, the sensitivity of digital exercise echocardiography was 89% and the specificity 92%. Regarding the presence or absence of exercise-induced ischaemia, intra-observer agreement ...
Marwick T H - - 1995
OBJECTIVES: This study examined the influence of left ventricular hypertrophy on the accuracy of exercise electrocardiography and echocardiography for detection of coronary artery disease. BACKGROUND: Electrocardiographic repolarization abnormalities caused by left ventricular hypertrophy compromise the diagnostic accuracy of exercise electrocardiography but not of exercise echocardiography. The relative merits of these ...
Kiat H - - 1995
OBJECTIVES: This study sought to evaluate the efficacy and safety of arbutamine when used in conjunction with thallium-201 single-photon emission computed tomography (SPECT) in a multicenter trial and to compare arbutamine stress and treadmill exercise thallium-201 SPECT for diagnostic sensitivity and myocardial perfusion pattern. BACKGROUND: Arbutamine is a potent beta-agonist ...
Seto H - - 1995
To improve the early detectability of gastrointestinal (GI) bleeding, we have developed a new subtraction scintigraphic technique using in vivo labeled 99mTc red blood cells (RBC). Use of this new sequential subtraction method every 5 min makes it possible to detect early the bleeding site and calculate the bleeding rate. ...
Bonow R O - - 1995
Exercise myocardial perfusion imaging and exercise echocardiography have been applied widely for diagnosis and risk stratification of patients with known or suspected coronary artery disease. The accuracy of these evaluations depends upon the ability of the patient to achieve maximal exercise (> 85% of age-predicted maximal heart rate). In patients ...
Michaelides A - - 1995
Previous studies have shown a good correlation between exercise-induced changes of Q-, R-, and S-waves (Athens QRS score) and the number of the obstructed coronary arteries. The present study was undertaken to test the hypothesis that abnormal Athens QRS score is related to exercise-induced myocardial ischemia. Patients who had exercise ...
Nielsen T G - - 1995
OBJECTIVES: To develop a simple protocol for ultrasound Duplex surveillance of infrainguinal vein bypasses. DESIGN: The value of three Doppler waveform parameters, obtained from a single point of the bypass, for identification of stenoses was studied in 91 in situ vein bypasses. Midgraft peak systolic velocity (PSV), pulsatility index (PI) ...
Marie P Y - - 1995
OBJECTIVES: This study sought to evaluate the prognostic role of exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT) in patients with known or suspected coronary artery disease. BACKGROUND: Compared with planar Tl-201 scintigraphy, Tl-201 SPECT allows enhanced assessment of myocardial perfusion abnormalities. However, the long-term prognostic value of exercise Tl-201 ...
Nicolai E - - 1995
The results of resting planar ECG-gated technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) imaging were compared with those of thallium-201 (Tl) re-injection after exercise-redistribution scintigraphy in 20 patients (19 men, 1 woman, mean age 53 +/- 10 years) with angiographically proven coronary artery disease. Eight normal subjects (seven men, one woman, mean age 50 ...
Cox J L - - 1995
OBJECTIVE: To compare the incidence of cardiac events among patients with increased lung uptake of thallium after dipyridamole stress, matched subjects without such uptake and matched subjects with increased lung uptake during exercise stress. DESIGN: Retrospective case control study based on quantitative and semiquantitative visual consensus analysis of thallium scintigraphy. ...
Lisbona R - - 1995
Aartifactual inferior wall defects of perfusion are a source of frequent concern during TI-201 exercise stress redistribution SPECT imaging in the supine position. These artifactual changes also affect Tc-99m sestamibi dipyridamole myocardial perfusion studies with supine SPECT yielding a specificity of only 58% for right coronary artery (RCA) disease. Complementary ...
Kao C H - - 1995
We reviewed the exercise thallium-201 (201Tl) myocardial single photon emission tomography (SPET) results and clinical data of 28 patients, adhering to a strict definition of syndrome X. All of the patients had a normal resting left ventricular ejection fraction (LVEF) and no cardiac abnormalities. The results of the exercise electrocardiography ...
Anagnostopoulos C - - 1995
Upward motion of the heart during tomographic data acquisition of stress TI-201 myocardial perfusion images may lead to artifacts in the reconstructed tomograms. The authors report a patient in whom this occurred, giving the impression of reversible perfusion defects. Although correction of the raw data abolished the artifact, a separate ...
Dagianti A - - 1995
OBJECTIVES: This study was designed to compare exercise, dipyridamole and dobutamine echocardiography in the same patients and to evaluate, by measuring physiologic and echocardiographic variables, the mechanisms by which exercise and dobutamine induce ischemia. BACKGROUND: The diagnostic value of stress echocardiography has been widely reported, but the specific effects of ...
Arnese M - - 1995
OBJECTIVES: This study sought to assess the value of quantitative coronary arteriography in predicting an ischemic response at exercise echocardiography and technetium-99m 2-methoxy isobutyl isonitrile (mibi) single-photon emission computed tomography (SPECT) in patients with single-vessel disease of the left anterior descending coronary artery. BACKGROUND: The relation between severity of coronary ...
Hurwitz G A - - 1995
High abdominal background activity of 99mTc-sestamibi may interfere with the diagnosis in studies in which a coronary vasodilator is used; supplemental dynamic exercise might reduce this problem. METHODS: Clinical and angiographic determinants of subdiaphragmatic-to-myocardial activity ratios were measured on immediate poststress left anterior oblique images and on corresponding tomographic studies ...
Touho H - - 1995
The haemodynamic mechanisms responsible for the appearance of paraparetic transient ischaemic attacks in ten patients with childhood moyamoya disease who subsequently underwent bifrontal omental transplantation were investigated. Cerebral perfusion (CP) was measured with 99mTc-hexamethylene-propyleneamine oxime single photon computed tomography prior to and after administration of acetazolamide. Cerebral perfusion was obtained ...
Mahmarian J J - - 1995
The purpose of this study was to define the reproducibility of sequential quantitative exercise thallium-201 tomography. This was an ancillary study of a randomized, double-blind, placebo-controlled trial evaluating the short-term efficacy of transdermal nitroglycerin patches in stable patients with angiographic coronary artery disease and no prior myocardial infarction. All 18 ...
Paillole C - - 1995
Coronary artery disease may be difficult to detect in diabetic patients. This study was designed to determine the specificity and sensitivity of three noninvasive tests. Accordingly, the results of 48-h ambulatory electrocardiogram (ECG) monitoring, maximal ECG exercise test, and intravenous dipyridamole myocardial thallium scintigraphy were compared in 59 middle-aged diabetic ...
Paridon S M - - 1995
OBJECTIVES: This study evaluated exercise performance and myocardial perfusion during exercise in patients with Kawasaki disease who had a broad spectrum of residual coronary abnormalities. BACKGROUND: Reports of exercise performance after Kawasaki disease have generally included a small number of patients evaluated by various protocols, frequently with incomplete data. Myocardial ...
Zeiher A M - - 1995
BACKGROUND: The release of endothelium-derived relaxing factors has been shown experimentally to be of pivotal importance for the maintenance of coronary blood flow during increased demand. In humans with coronary atherosclerosis, endothelial vasodilator dysfunction is not confined only to epicardial conductance vessels but may also extend into the coronary microcirculation. ...
Morise A P - - 1995
BACKGROUND: The goal was to assess the incremental diagnostic value of thallium single-photon emission computed tomographic (SPECT) imaging and lung/heart ratio (LHR) over other clinical and exercise electrocardiographic (ECG) variables concerning the presence and extent (three vessel/left main) of coronary artery disease. METHODS AND RESULTS: Multivariable logistic regression analysis that ...
Pirelli S - - 1995
It is now widely accepted that percutaneous transluminal coronary angioplasty (PTCA) is an effective nonsurgical technique for achieving coronary revascularization. Exercise electrocardiography remains the standard procedure for functional evaluation before, early, and late after angioplasty because of its availability, safety, and limited cost. The drawback of exercise testing is its ...
Talbot P R - - 1995
The purpose of this study was to examine the possible association between "classic" motor neuron disease (cMND) and frontotemporal dementia (FTD), using neuropsychological evaluation and single photon emission computed tomography (SPECT). Psychological tests assessing language, perceptuospatial, memory, and "frontal lobe" functions were given to patients with cMND and test scores ...
Cavell R M - - 1995
After more than 50 years of refinement, the exercise test remains a useful device for diagnosis and prognosis of coronary artery disease. In addition, it is within the range of skills of primary care physicians. Understanding that the exercise test is not a noninvasive angiogram, and that angiography primarily defines ...
Pennell D J - - 1995
OBJECTIVES: This study investigated whether combining exercise with adenosine would reduce the adverse effects of adenosine vasodilation. BACKGROUND: Adenosine vasodilation is effective for perfusion imaging but causes frequent unpleasant noncardiac adverse effects, high noncardiac tracer uptake and occasional arrhythmias. METHODS: Of 500 consecutive patients referred for thallium-201 myocardial perfusion imaging, ...
O'Keefe J H JH - - 1995
The cumulative published literature dealing with the most frequently utilized noninvasive cardiac stress imaging modalities (radionuclide myocardial perfusion scintigraphy and echocardiography) was reviewed to gain insight on their comparative diagnostic accuracies. To be included, studies had to be performed in conjunction with exercise or a commonly used intravenous pharmacologic stress ...
Kafka H - - 1995
OBJECTIVES: Our aim was to assess, in patients after coronary artery bypass surgery, how well exercise echocardiography predicts the presence of vascular compromise on angiography. BACKGROUND: Because late graft failure frequently occurs after bypass surgery, a reliable noninvasive technique is needed to identify those patients who would benefit from angiographic ...
Stein L - - 1995
Exercise combined with dipyridamole during thallium stress testing in patients with coronary artery disease (CAD) increases the frequency of angina and ischemic ST changes in the electrocardiogram. Evidence for an increase in thallium abnormalities has been inconclusive. We prospectively examined 54 consecutive patients who underwent coronary angiography and tomographic thallium ...
Nallamothu N - - 1995
OBJECTIVES: This study compared the diagnostic accuracy of exercise thallium-201 single-photon emission computed tomography (SPECT) with the exercise electrocardiographic (ECG) response in patients with normal baseline ECG results. BACKGROUND: Previous studies comparing exercise thallium imaging with exercise electrocardiography have included patients with abnormal rest ECG results that may have biased ...
Atar D - - 1995
The aim of the study was to assess the diagnostic value of bicycle exercise echocardiography using quantitative coronary arteriography as a reference. Exercise echocardiography was performed in 70 consecutive patients referred for coronary angiography. Digital loops were obtained at rest, peak, and immediately after exercise in the standard views (parasternal ...
Pancholy S B - - 1995
BACKGROUND: This study examined the independent and incremental prognostic value of exercise thallium single-photon emission computed tomographic imaging in 212 women who also underwent coronary angiography. METHODS AND RESULTS: The left ventricular ejection fraction was normal (65% +/- 15%). During a mean follow-up of 40 months, 27 women had events ...
Burns R J - - 1995
BACKGROUND: 99mTc-labeled teboroxime undergoes rapid washout from the myocardium. For this reason, its use has been favored in conjunction with pharmacologic stress, which enables patient positioning before tracer administration, and multidetector single-photon emission computed tomography (SPECT), which enables rapid acquisition. We evaluated treadmill exercise 99mTc-labeled teboroxime SPECT with single-detector systems ...
Göller V - - 1995
BACKGROUND: Although nitrates were introduced more than 100 years ago and have been used for the treatment of angina pectoris, there are still some open questions concerning the mechanism of their action on myocardial ischemia. There are also insufficient data regarding the influence of any anti-ischemic medication on the results ...
< 3 4 5 6 7 8 9 10 11 12 13 >