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Turski W A - - 2000
We evaluated the effects of replacing the standard St. Thomas Hospital (ST) cardioplegic fluid with Bretschneider (BR) fluid during coronary-aortal bypass graft operation (CABG) in patients with coronary disease. BR fluid contains enormous concentration of histidine (approximately 0.2 mole L-1): thus increased levels of histamine or other metabolites might exert ...
Gullestad L - - 2000
BACKGROUND: Neurohormones may influence vascular tone both during and after exercise. Neuropeptide Y (NPY), which is costored and released with norepinephrine (NE) during sympathetic activity, is a potent vasoconstrictor with a relatively long half-life. We therefore examined its possible association with the ischemic response to exercise in patients with coronary ...
Shimizu M - - 2000
BACKGROUND: ST-segment depression is common in patients with hypertrophic cardiomyopathy (HCM). However, it is not clear whether exercise-induced ST-segment depression in patients with HCM and patent coronary arteries is associated with changes in left ventricular function. METHODS: Left ventricular function was continuously evaluated in 53 patients with nonobstructive HCM during ...
Kay I P - - 2000
BACKGROUND: Proposed mechanisms for "warm-up" after angina on first exercise include ischemic preconditioning and collateral recruitment. The aim of this study was to determine whether patients with ischemic heart disease and well-developed coronary collateral vessels have a greater warm-up response than those with no visible collateral vessels. METHODS AND RESULTS: ...
Ovünç K - - 2000
BACKGROUND: Warm-up phenomenon, one of the clinical models of ischemic preconditioning, refers to an increased tolerance to myocardial ischemia during the second of two consecutive exercise tests. HYPOTHESIS: Blockers of K(ATP) channels, such as the sulfonylurea drugs, can induce loss of ischemic preconditioning. This study aimed to investigate the effects ...
Kodama K - - 2000
The transient U wave inversion during exercise is specific for detecting left anterior descending coronary artery (LAD) disease. In a homogeneous patient group restricted to LAD disease, however, the significance of the electrocardiographic finding has not yet been clarified. Thus, clinical characteristics in patients with angiographically documented one-vessel disease of ...
Fragasso G - - 2000
BACKGROUND: Recent studies have indicated that heparin administration might decrease endothelial nitric oxide production. The aim of this study was to investigate the effect of heparin on ischemic threshold. METHODS: Eighteen patients with a positive exercise test and proven coronary artery disease were submitted to a randomized, placebo-controlled trial using ...
Shah P P - - 2000
False-positive exercise testing in patients with an accessory pathway has been described only in patients with manifest preexcitation during exercise. We describe a patient in whom marked ST-segment changes were seen during an exercise test in the absence of any preexcitation of the QRS complexes. The role of the accessory ...
Hayat N H - - 2000
OBJECTIVE: We prospectively studied the course of exercise induced positive U-wave before and after percutaneous transluminal coronary angioplasty (angioplasty). BACKGROUND: Negative U-wave in ECG is known to be associated with the myocardial ischemia in the territory of the left anterior descending artery. Positive U-wave needs further evaluation to prove its ...
Mezilis N E - - 2000
AIMS: The association between stress-induced ST elevation and functional recovery following revascularization after myocardial infarction remains unclear. We assessed the relative accuracy of dobutamine- and exercise-induced ST elevation in Q wave leads in predicting functional recovery following revascularization, and we investigated the relationship of ST elevation to different wall motion ...
Koide Y - - 2000
It has recently been reported that increased QT dispersion seen on standard 12-lead electrocardiograms (ECGs) reflects transient myocardial ischemia. The present study investigates whether increased QT dispersion induced by exercise is a useful indicator for detecting significant coronary stenosis in patients who do not have chest pain or significant ST-segment ...
Fearon W F - - 2000
OBJECTIVES: The aim of this study is to demonstrate the effect of resting ST segment depression on the diagnostic characteristics of the exercise treadmill test. BACKGROUND: Previous studies evaluating the effect of resting ST segment depression on the diagnostic characteristics of exercise treadmill test have been conducted on relatively small ...
Shono M - - 2000
Our aim is to evaluate serial changes in normal full-term fetal cerebral circulation according to the behavioral states. Flow velocity waveforms in the middle cerebral artery and fetal heart rate (FHR) were well recorded in ten of 19 cases by pulsed Doppler ultrasonography and actocardiography over 45 min, respectively. Behavioral ...
Mess W H - - 2000
Research on microembolic signals (MES) using the dual-gate technique has shown promising results, when the time difference (Deltat) of a MES in two sample volumes (SVs) placed serially has been measured manually. On the other hand, the computerized discrimination of MES and artefacts has been reported not to be superior ...
Kauppinen P K - - 2000
Whole-body impedance cardiography (ICGWB) has been proposed as a feasible means of measuring cardiac output (CO). However, the source distribution of heart-related impedance variations in the whole body is not known. To establish how much of a signal originates in each segment of the body and what the contribution of ...
Watanabe T - - 2000
OBJECTIVE: ST-segment depression is believed as a common electrocardiographic sign of myocardial ischemia during exercise testing. Ischemia is generally defined as oxygen deprivation due to reduced perfusion. However, the exact relationship of the ischemic definition to ST-segment depression remains unclear. This study was conducted to evaluate the correlation between myocardial ...
Abboud L - - 2000
OBJECTIVES: To evaluate the long-term predictive value of exercise testing performed early after acute myocardial infarction (AMI) in patients receiving thrombolytic therapy. DESIGN: Nonblinded prospective follow-up study. SETTING: Cardiac rehabilitation unit in a 900-bed university hospital. SUBJECTS: Four hundred forty-three patients allowed to perform exercise testing 3 weeks after AMI ...
Kay P - - 2000
OBJECTIVE: To determine the importance of the duration and intensity of "warm up" exercise for reducing ischaemia during second exercise in patients with exertional angina. DESIGN: Randomised crossover comparison of three warm up exercise protocols. PATIENTS: 18 subjects with stable ischaemic heart disease and > 0.1 mV ST segment depression ...
Miller T D - - 2000
STUDY OBJECTIVES: To determine if a history of hypertension or an exaggerated rise in exercise systolic BP is associated with a false-positive exercise ECG. DESIGN, SETTING, AND PATIENTS: Retrospective analysis of the associations between exercise-induced ST-segment depression and a history of hypertension, exercise systolic BP, and several other clinical and ...
Dreger R W - - 1999
The purpose of this study was to investigate a protocol for the determination of VO2 max utilizing a motor-driven skate treadmill (ST). On separate days, 6 male hockey players completed a ST and a cycle ergometer (BK) VO2 max protocol. The results showed no significant difference between the ST and ...
Nakago K - - 1999
The influence of mild exercise on skeletal muscle fibers was investigated histochemically to assess the effects of exercise on steroid myopathy and its efficacy for preventing this disease. Twenty male Wistar rats were divided into 4 groups of 5 each: group T, which received exercise alone; group S which received ...
Stevens C F - - 1999
During intense presynaptic activity, the readily releasable pool (RRP) of synaptic vesicles empties more quickly than it can be refilled, and short-term depression results. Ordinarily, the pool refills within 20 s, but long, high-frequency trains of action potentials often induce a form of short-term depression that persists for a much ...
Willis R - - 1999
A young St Bernard dog was referred on three separate occasions for investigation of dyspnea and exercise intolerance. Electrocardiography was performed on each occasion and showed various forms of supraventricular tachycardia with aberrant conduction. Echocardiography showed a progressive decrease in systolic function and thoracic radiographs showed progressive cardiomegaly. The arrhythmia ...
Forslund L - - 1999
The prognostic significance of ambulatory ischemia, alone and in relation to ischemia during exercise was assessed in 686 patients (475 men) with chronic stable angina pectoris taking part in the Angina Prognosis Study In Stockholm (APSIS), who had 24-hour ambulatory electrocardiographic registrations and exercise tests at baseline (n = 678) ...
Placanica G - - 1999
BACKGROUND: The aim of this study was to evaluate the plasma concentration of a platelet-derived protein, platelet factor 4 (PF4), before and after exercise in coronary artery disease. METHODS: We enrolled 60 patients with documented ischemic heart disease. The subjects were divided into two groups: Group 1 patients with previous ...
Buschbacher R M - - 1999
The ulnar antidromic sensory conduction study to the fifth digit is commonly performed in clinical electrodiagnosis. Several authors have published normal ranges for this study, but these published reports have been limited by generally small sample sizes. The purpose of this article is to present a large database of normal ...
Koide Y - - 1999
BACKGROUND: Treadmill exercise electrocardiography (ECG) has been used to detect restenosis in patients following percutaneous transluminal coronary angioplasty (PTCA). However, the level of sensitivity achieved using conventional criteria of ST-segment depression is too low to be clinically useful in this population. HYPOTHESIS: QT dispersion is a sensitive method for detecting ...
Jørgensen L H - - 1999
BACKGROUND: The mechanisms underlying exertional hyperpnea in patients with coronary artery disease and transient left ventricular dysfunction are still not fully understood. HYPOTHESIS: The study was undertaken to investigate whether the ventilatory response to exercise reflects the effects of acute medical treatment of exercise-induced left ventricular dysfunction, and to evaluate ...
Sueda S - - 1999
Some patients with variant angina show both ST segment elevation at rest and exercise-induced ST segment elevation. Magnesium deficiency has also been observed in patients with variant angina. This study investigated the correlation between the degree of magnesium deficiency and the efficacy of intravenous administration of magnesium in patients with ...
Mammana C - - 1999
BACKGROUND: The diagnostic value of exercise electrocardiography (ECG) in patients with complete right bundle block (cRBBB) remains controversial. The aim of this study was to investigate the diagnostic accuracy of exercise ECG for predicting ischemia in the presence of cRBBB. METHODS: From a series of 1300 consecutive patients attending for ...
Kobayashi N - - 1999
BACKGROUND: Results of recent studies show that intracoronary administration of L-arginine, the precursor of nitric oxide, restores endothelial function in subjects with coronary risk factors and minimal coronary artery lesions. However, few investigators have examined the clinical feasibility of using L-arginine for treatment of myocardial ischemia due to coronary artery ...
Aytemir K - - 1999
BACKGROUND: ST-segment depression during exercise testing is frequently observed in the absence of restenosis after percutaneous transluminal coronary angioplasty (PTCA). HYPOTHESIS: With the goal of improving the prediction of restenosis after PTCA, we evaluated the usefulness of ST-segment depression plus QT dispersion (QTd = QTmax - QTmin) during treadmill stress ...
Bodí V - - 1999
BACKGROUND: Resting ST-segment elevation on Q leads after an acute myocardial infarction has been related to a greater infarct size. Otherwise, the relation between exercise-induced ST-segment elevation and myocardial viability is controversial. We investigated the relation between ST-segment elevation on Q leads at rest and during exercise and regional dysfunction ...
Vaage-Nilsen M - - 1999
BACKGROUND: Although ST-segment deviation has been evaluated and used during many years both on continuous electrocardiographic Holter monitoring and during exercise stress testing, considerable controversy still remains concerning the prevalence and diagnostic significance of fortuitously discovered ST-segment deviation in asymptomatic healthy persons. METHODS AND RESULTS: The occurrence of ST-segment deviation ...
Martin S L - - 1999
The biochemical mechanisms by which hibernators cool as they enter torpor are not fully understood. In order to examine whether rates of substrate oxidation vary as a function of hibernation, liver mitochondria were isolated from telemetered ground squirrels (Spermophilus lateralis) in five phases of their annual hibernation cycle: summer active, ...
Lauer M S - - 1999
By incorporating additional data, clinicians can transform the exercise stress test from a poor diagnostic test to a good prognostic one. These additional data include indices of how the patient's heart rate and blood pressure respond to exercise. Computerized measures of electrocardiographic ST-segment changes that adjust for heart rate also ...
Rosano G M - - 1999
BACKGROUND: The role of testosterone on the development of coronary artery disease in men is controversial. The evidence that men have a greater incidence of coronary artery disease than women of a similar age suggests a possible causal role of testosterone. Conversely, recent studies have shown that the hormone improves ...
Musha H - - 1999
The difference between the maximum and minimum QT intervals on the standard 12-lead ECG (QT dispersion) may be a significant predictor of serious arrhythmias. Dynamic changes in QTd were determined during exercise-induced ischemia in 15 patients with effort angina (> or = 75% coronary stenosis) and 10 normal individuals. Treadmill ...
Tomai F - - 1999
AIMS: The increased tolerance to myocardial ischaemia observed during the second of two sequential exercise tests, i.e. the warm-up phenomenon, has been proposed as a clinical model of ischaemic preconditioning. As ATP-sensitive K+ channels appear to be a mediator of ischaemic preconditioning in both experimental and clinical studies, the aim ...
Hardin J A JA Gastrointestinal Research Group, University of Calgary, Alberta, - - 1999
Although many studies have investigated macromolecular uptake in the stomach and small intestine, little is known about macromolecular uptake in the colon. To investigate the mechanisms involved in the transport of large antigenically intact macromolecules across the proximal and distal colonic epithelium in the rabbit. The mucosal to serosal movement ...
Rutter M K - - 1999
Microalbuminuria is an increase in urinary albumin not detected by conventional dipstick testing and is present in 20% of patients with non-insulin-dependent diabetes mellitus (NIDDM). Mortality in NIDDM patients with microalbuminuria is 60% at 8 years and is mainly due to cardiovascular disease. Because many deaths occur without warning symptoms, ...
Lehtinen R - - 1999
ST segment depression/heart rate (ST/HR) hysteresis is a recently introduced novel computer method for integrating the exercise and recovery phase ST/HR analysis for improved detection of coronary artery disease (CAD). It is a continuous diagnostic variable that extracts the prevailing direction and average magnitude of the hysteresis in ST depression ...
Biłan A - - 1999
The ESS-1 study was designed to evaluate the long-term effects of the angiotensin-converting enzyme inhibitor (ACEI) enalapril (10 mg per day) on cardiopulmonary system of patients with systemic sclerosis (SSc). Exercise testing is used not only for estimation of coronary reserve but also physical capacity--the major determinant of quality of ...
Takaki H - - 1999
Although exercise-induced QRS prolongation has been reported as a possible marker for inducible ischemia, subtleness of the prolongation makes it unidentifiable from standard, chart-recorded electrocardiograms (ECGs). To overcome such a limitation, we measured the QRS width using high-resolution ECGs and examined the diagnostic value of the exercise-induced QRS prolongation in ...
Viik J - - 1999
We have studied the effect of the number and ordering of exercise electrocardiographic (ECG) leads when using the maximum value of the ST segment depression/heart rate (ST/HR) hysteresis over a different number of leads for the detection of coronary artery disease (CAD). The study population consisted of 127 patients with ...
Walamies M A - - 1999
A slowly upsloping ST segment depression is an abnormal, and a rapidly upsloping ST segment depression is a normal exercise ECG response. We investigated the agreement of expert physicians on the visual classification of the ST segment depression, and compared the (majority) vote with the computer-generated ST slope. A total ...
Toyofuku M - - 1999
To test the hypothesis that local or diffuse wall motion abnormalities in the right ventricle in patients with arrhythmogenic right ventricular dysplasia (ARVD) may induce the ST-segment elevation in response to exercise, we examined exercise electrocardiograms in patients with ARVD. In 17 patients with ARVD, who demonstrated right ventricular wall ...
Charlton T - - 1998
This article refers to a naturalistic study of broadcast television's effects upon the social behaviour of young pupils in St Helena, South Atlantic. Interim findings showed that 2 years after the availability of television, the good behaviour noted before television arrived had been maintained. Explanations for the continuance of good ...
Bøtker H E - - 1998
A significant proportion of patients with cardiac syndrome X have impaired coronary vasodilator capacity, which is thought to be caused by an increased sympathetic drive. The alpha1-adrenoceptor blocker, doxazosin, increases the coronary vasodilator reserve in patients with syndrome X. To study whether the augmentation is associated with clinical improvement in ...
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 ...
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