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Results 301 - 350 of 929
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Tanaka T - - 1998
OBJECTIVES: The purpose of this study was to evaluate whether a serotonin blocker, sarpogrelate, improves exercise capacity as a result of vasodilation of coronary collateral channels in patients with effort angina. BACKGROUND: Serotonin has been reported to decrease coronary collateral blood flow by collateral vasoconstriction in a canine model, suggesting ...
Bogaty P - - 1998
OBJECTIVES: This study characterized the attenuation of myocardial ischemia observed with re-exercise to determine whether: 1) a differing exercise intensity modifies this attenuation; 2) it could be explained by contractile down-regulation or stunning; 3) it is mediated by activation of ATP-sensitive potassium channels (K+-ATP). BACKGROUND: Subjects with ischemic heart disease ...
Andersson J L - - 1998
The morphology of intracardiac electrograms (IEGMs) was used for pacemaker patient workload estimation. The body posture also was studied as another characteristic. The IEGMs were obtained and recorded via temporary transcutaneous leads connected to the implanted pacemaker. IEGMs were recorded during exercise and at rest. Recordings at rest were performed ...
Do D - - 1998
Currently the standard exercise test is shifting from being a tool for the cardiologist to utilization by the nonspecialist. This change could be facilitated by computerization similar to the interpretation programs available for the resting ECG. Therefore, we sought to determine if computerization of both exercise ECG measurements and prediction ...
Cantor A - - 1998
AIM: To compare the diagnostic accuracy of exercise electrocardiographic (ECG) ST-T changes and QRS duration changes as a means of ischemia detection in a female population. METHODS AND RESULTS: A total of 101 women from a pool of 318 referred for ECG stress testing underwent standard testing using ST-T criteria ...
Ibrahim N S - - 1998
We compared 12-lead electrocardiographic changes during exercise in 41 patients with left bundle branch block; 7 were nonischemic and 34 had coronary artery obstruction > or =70% as detected by angiogram. ST depression of > or =0.5 mm from baseline when measured at the J point in leads II and ...
Watanabe T - - 1998
BACKGROUND: Ischemic ST-segment depression (horizontal or downsloping) is the most common manifestation of exercise-induced myocardial ischemia. The mechanisms responsible for these types of ST-segment depression are largely unknown. We investigated the relation of these 2 types of exercise-induced ST-segment depression to changes in regional myocardial blood flow (RMBF) by using ...
van den Bosch W A - - 1998
The goal of this article is to investigate the effect of Graves orbitopathy and orbital decompression on the position of the eyeball, and to relate this to a straight upper eyelid contour, observed in several patients after correction of upper eyelid retraction. The positions of the pupil center and the ...
Atwood J E - - 1998
BACKGROUND: The type of practitioners who use the standard exercise test is changing. Once a tool of the cardiologist, the standard exercise test is now being performed by internists and other noncardiologists. Because this change could be facilitated by computerization similar to the computerized interpretation programs available for the resting ...
Hambly M F - - 1998
STUDY DESIGN: The clinical and radiographic effect of a lumbar or lumbosacral fusion was studied in 42 patients who had undergone a posterolateral fusion with an average follow-up of 22.6 years. OBJECTIVE: To examine the long-term effects of posterolateral lumbar or lumbosacral fusion on the cephalad two motion segments (transition ...
Zaslavsky C - - 1998
BACKGROUND: In most instances, constipation is considered idiopathic or functional. The total and segmental colonic transit time, traced by radio- opaque markers, makes possible the identification of the colon segment that has the motility alteration that causes constipation. METHODS: A study was performed of 13 adolescents, aged 12 to 18, ...
Mitrovic V - - 1998
BACKGROUND: Tedisamil is a new bradycardic agent proven to exert anti-ischemic and antiarrhythmic effects by blockade of the different cardiac and vascular K+ currents. HYPOTHESIS: It was the aim of the present study to compare the favorable anti-ischemic effects of tedisamil, with two long established representatives in the treatment of ...
Michaelides A P - - 1998
The clinical value of exercise-induced variations in ST-segment depression and R wave amplitude in consecutive sinus beats was studied in 160 patients who had a positive treadmill exercise test with the Bruce protocol. The patients, all of whom underwent cardiac catheterization, included 100 with coronary artery disease (CAD) (group with ...
Myrianthefs M M - - 1998
The aim of this study was to investigate exercise-induced ST-segment depression in subjects with a 120-ms or shorter PR segment and normal coronary arteries. A population of 86 individuals who demonstrated ST-segment depression of 1.5 mm or more on treadmill testing and had a subsequent normal coronary arteriography was classified ...
Rywik T M - - 1998
BACKGROUND: Although exercise-induced ST depression is an independent predictor of future coronary events in asymptomatic populations, the predictive value of ST depression beginning after exercise cessation is unknown. METHODS AND RESULTS: We analyzed the treadmill exercise tests of 825 healthy volunteers who were 22 to 89 years of age from ...
Trimble M H - - 1998
Post-muscle activation effects on segmental reflexes reveal divergent results dependent upon the manner in which the muscle is activated. Electrically activating triceps surae invokes a potentiation of the Achilles' tendon reflex and the soleus (S) H-reflex termed posttetanic potentiation. In contrast, brief volitional activation produces a subsequent potentiation of tendon ...
Viik J - - 1998
In this study we compared the diagnostic characteristics of the individual exercise electrocardiographic leads, 3 different lead sets comprising standard leads and the effect of the partition value in the detection of coronary artery disease (CAD). The diagnostic variable used was ST-segment depression at peak exercise, and the study population ...
Forslund L - - 1998
AIMS: To evaluate signs of ischaemia and ventricular arrhythmias in relation to gender and sympathoadrenal activity in patients with stable angina pectoris and healthy controls. MATERIAL AND METHODS: 809 patients (248 females) with stable angina pectoris, and 50 matched healthy controls performed an exercise test and an ambulatory ECG recording. ...
Agarwal P - - 1998
Thirty four healthy young male subjects performed symptom limited exercise on Bruce protocol on treadmill machine. Hyperventilation induced labile repolarisation ST-T abnormalities were observed in 2 whereas exercise induced ST changes (upsloping ST depression in 4 and horizontal ST depression in 1) were observed in 5 additional candidates. Changes were ...
Mannheimer C - - 1998
BACKGROUND: Spinal cord stimulation (SCS) has been shown to have antianginal and anti-ischemic effects in severe angina pectoris. The present study was performed to investigate whether SCS can be used as an alternative to coronary artery bypass grafting (CABG) in selected patient groups, ie, patients with no proven prognostic benefit ...
Mawson D M - - 1998
CapiFlow (CF), a new fully computerized system for the measurement of capillary blood velocity (CBV) was compared to manual frame by frame analysis (a) in a model system, and (b) in finger nailfold capillaries recorded on video tape. In the model the overall agreement between the two methods was very ...
Liu Y B - - 1998
The S-T segment/heart rate (ST/HR) slope has been proposed as a more accurate electrocardiographic criterion for the diagnosis of coronary artery disease, but studies comparing the diagnostic value of the ST/HR slope with exercise thallium imaging are scant. The aims of this study were to assess the diagnostic accuracy of ...
Tatara T - - 1998
OBJECTIVE: To determine whether the segmental multifrequency bioelectrical impedance analysis may improve the prediction for intraoperative changes in extracellular water volume (deltaECW) compared with whole body multifrequency bioelectrical impedance analysis in abdominal surgical patients. DESIGN: Prospective, consecutive sample. SETTING: Surgical operative patients in a university-affiliated city hospital. PATIENTS: Thirty patients ...
Michaelides A P - - 1998
BACKGROUND: Exercise-induced ST-segment changes 3 months after angioplasty may sometimes show a false-positive result. METHODS: We therefore analyzed the ST changes observed during the exercise tests performed before and 3 months after angioplasty in 118 patients with single-vessel coronary artery disease. RESULTS: Ninety-two (78%) of the 118 patients had ST ...
Heard S O - - 1998
OBJECTIVE: To evaluate the efficacy of triple-lumen central venous catheters coated with a combination product of chlorhexidine and silver sulfadiazine (CSS) in reducing the incidence of local catheter infection and catheter-related bacteremia. DESIGN: Randomized, controlled trial. SETTING: The surgical intensive care units in a university hospital. PATIENTS: All patients who ...
Nalbantgil I - - 1998
OBJECTIVES: Although the pathophysiology of syndrome X (angina pectoris, positive ECG test findings and normal coronary arteriogram) is unclear, it is generally accepted that intracellular metabolic changes resulting from abnormal constriction of prearteriolar vessels due to endothelium-dependent vasodilation abnormalities may play a role in the pathogenesis. We established the effect ...
Michaelides A P - - 1998
Exercise-induced ST-segment changes 3 months after angioplasty sometimes may show a false-positive result. We therefore analyzed the ST changes observed during the exercise tests performed before and 3 months after angioplasty in 118 patients with single-vessel coronary artery disease. Ninety-two (78%) of the 118 patients had ST changes in the ...
Franz I - - 1998
BACKGROUND: The pump function during exercise can be disturbed not only in hypertensives with coronary artery disease (CAD), but also in those with a normal angiogram. METHODS: In 10 hypertensive patients (group 1; aged 52+/-4 years, 1 men, 9 women) with ST segment depression during exercise and concomitant angina pectoris ...
Chandler M P - - 1997
Arterial pressure, cardiac sympathetic tonus (ST), and heart rate (HR) are reduced after a single bout of dynamic exercise in spontaneously hypertensive rats (SHR). To test if the arterial baroreflex is required for these postexercise responses, intact (n = 9) and sinoaortic-denervated (SAD) rats (n = 5) were chronically instrumented ...
Lehtinen R - - 1997
To evaluate the effect of ST-segment measurement point on diagnostic performance of the ST-segment/heart rate (ST/HR) hysteresis, the ST/HR index, and the end-exercise ST-segment depression in the detection of coronary artery disease, we analysed the exercise electrocardiograms of 347 patients using ST-segment depression measured at 0, 20, 40, 60 and ...
Morise A P - - 1997
We compared the accuracy of the ST segment/heart rate (STHR) index and slope to standard criteria (> or =1 mm horizontal/downsloping ST-segment depression at J + 60 msec) in 1358 patients (152 underwent angiography). All exercise tests used the Cornell protocol and computer measurements of maximum ST-segment depression at J ...
Viik J - - 1997
Several methods of heart rate-adjusted ST segment (ST/HR) analysis have been suggested to improve the diagnostic accuracy of exercise electrocardiography in the identification of coronary artery disease compared with traditional ST segment analysis. However, no comprehensive comparison of these methods on a lead-by-lead basis in all 12 electrocardiographic leads has ...
Cantor A - - 1997
This study compared thallium stress testing and exercise changes in QRS duration using a computerized 'optic scanner' in three groups. Group 1 consisted of 108 subjects with positive exercise ECG tests by ST-T segment criteria and with proven coronary artery disease. Group 2 included 19 subjects with nondiagnostic exercise ECG ...
Kamalesh M - - 1997
The angiographic, echocardiographic, and electrocardiographic correlates of ST-segment elevation during high-dose dobutamine-atropine stress were prospectively looked at in a group of high-risk patients. Unlike exercise-induced ST elevation, ST-segment elevation with dobutamine-atropine stress, while indicating transmural ischemia, did not increase rate of arrhythmias and hence by itself may not be an ...
Schulman D S - - 1997
We compared exercise test results to a physiologic depiction of stenosis severity, coronary flow reserve (CFR), measured with a Doppler guide wire in 35 patients with single-vessel coronary disease. Group 1 (n = 21) had abnormal CFR, and group 2 (n = 14) had normal CFR. In group 1, 14 ...
Samniah N - - 1997
The accuracy of commercially available ambulatory electrocardiographic monitoring (AEM) systems for reproducing ischemic changes has been questioned. Since these systems are widely used for evaluation of ST-segment changes, both for prognostic purposes and for assessment of the efficacy of antiischemic drugs, such doubts must be clarified. For this purpose, we ...
Ahmed M W - - 1997
The purpose of this study was to assess the effects of autonomic stimulation and blockade on noise levels and to compare the noise measurements in the ST and TP segments of the signal-averaged ECG. Five-minute electrocardiographic data were recorded in 14 normal volunteers (8 males and 6 females; mean age ...
Bogaty P - - 1997
OBJECTIVES: We explored how the exercise electrocardiographic (ECG) indexes generally presumed to signify severe ischemic heart disease (IHD) correlate with coronary angiographic and scintigraphic myocardial perfusion findings. BACKGROUND: In exercise testing, it is generally assumed that the early onset of ST segment depression and its occurrence at a low rate-pressure ...
Elliott P M - - 1997
BACKGROUND: Patients with syndrome X (exertional angina, positive exercise test, normal coronary arteriogram) have an altered perception of cardiac pain. This symptom may arise from increased sensitivity to adenosine. Previous studies suggest that intravenous aminophylline (an adenosine receptor blocker) improves exercise tolerance in patients with this disorder. OBJECTIVE: To examine ...
Katzel L I - - 1997
OBJECTIVE: To determine the effects of 3 months of voluntary deconditioning on cardiac function in master athletes. DESIGN: A prospective study. SETTING: Research participants at the University of Maryland School of Medicine and Johns Hopkins Bayview Medical Center. PARTICIPANTS: Ten older (59 +/- 8 years, mean +/- SD), highly conditioned ...
Iwasaki S - - 1997
A small region of microcirculation disorder in the cochlea of the guinea pig could be induced by a photochemical reaction. Photoillumination to the cochlea was done after systemic infusion of Rose Bengal (RB). The lateral wall of the second or third turn of the cochlea was illuminated for 10 min ...
Lehtinen R - - 1997
The reproducibility of the ST-segment depression against heart rate (ST/HR) hysteresis, ST/HR index, and end-exercise ST depression between the repeated exercise electrocardiographic tests were determined in 61 asymptomatic middle-aged subjects. The findings support the clinical utility of the ST/HR hysteresis, but it is noteworthy that the results also suggest that ...
Madias J E - - 1997
Exercise electrocardiogram (ECG) has a high rate of false negative results in comparison with simultaneously performed thallium-201 perfusion scintigraphy, particularly in patients with single-vessel coronary artery disease, low exercise workload, inadequate heart rate rise, and resting ECG abnormalities. We present the case of a patient in whom thallium-201 SPECT scintigram ...
Mickelson J K - - 1997
BACKGROUND: Interpretation of exercise tests as positive or negative is primarily based upon exercise-induced ST segment changes. Consistently accurate measurements are difficult to obtain during exercise. HYPOTHESIS: This study compared on-line computer-generated electrocardiographic (ECG) analysis with visual interpretation. The goals were to document the extent of agreement, establish reasons for ...
Tomai F - - 1997
The increased tolerance to myocardial ischemia observed during the second of two sequential exercise tests, i.e. the warm-up phenomenon, has been proposed as a clinical model of ischemic preconditioning. Adenosine appears to be a mediator of ischemic preconditioning in both experimental and clinical settings. The purpose of this study was ...
Sansoy V - - 1997
The supplementary value of varying degrees of upsloping ST-segment depression observed during treadmill exercise testing to the accuracy of the exercise ST-segment response for detection of ischemia was determined by employing a reversible thallium-201 (201Tl) defect as the criteria for ischemia. A group of 199 consecutive patients (168 men) with ...
Watanabe T - - 1997
Exercise-induced downsloping ST-segment depression is a common manifestation of severe myocardial ischemia. Although greater downsloping ST-segment depression is suspected to indicate more severe ischemia, its exact relationship to regional myocardial blood flow (RMBF) has not yet been clarified. We investigated the relationship between the magnitude of downsloping ST-segment depression and ...
Calvert C A - - 1997
OBJECTIVES: To establish data for selected variables of the signal-averaged ECG and determine whether sedation affects segment lengths and points within the terminal QRS complex where windows began. SAMPLE POPULATION: Overtly healthy dogs with no detected abnormalities. PROCEDURE: Signal-averaged ECG (600 beats) were obtained from dogs in left-lateral recumbency, using ...
Legrand V - - 1997
To determine whether metallic stent implantation within a coronary artery modifies the accuracy of angina or exercise test results in predicting stenosis, we studied 172 patients assigned to stent implantation and 153 patients assigned to balloon angioplasty enrolled in the Benestent trial comparing de novo stenting with conventional balloon angioplasty. ...
Kearney M T - - 1997
OBJECTIVES: This study aimed to explore the hemodynamic responses to ingestion of meals of different composition in patients with chronic stable angina and to assess the effect of these meals on time to onset of > 1-mm ST segment depression and limiting angina pectoris during exercise. BACKGROUND: To our knowledge, ...
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