Search Results
Results 301 - 350 of 727
< 2 3 4 5 6 7 8 9 10 11 12 >
Geirsson A J - - 1996
To examine left ventricular (LV) myocardial perfusion and function, in systemic sclerosis. Myocardial perfusion was assessed at rest, during cold exposure, and at peak exercise in 10 patients with systemic sclerosis. Seven of the 10 patients were examined with Doppler echocardiography; before and after long-term diltiazem treatment. Compared with average ...
Dodd-o J M - - 1996
This study tested the hypothesis that an alpha-adrenergic coronary constrictor tone increases with the intensity of exercise and imposes a limitation on transmural myocardial blood flow and contractile function during strenuous levels of exercise. Nine (9) dogs were chronically instrumented to measure left circumflex blood flow (CBF), global myocardial contractile ...
Treffner P J PJ Center for the Ecological Study of Perception and Action, University of Connecticut, Storrs, USA. - - 1996
The symmetrical dynamics of 1:1 rhythmic bimanual coordination may be specified by an order parameter equation involving the relative phase between rhythmic components, and an interlimb coupling which determines the relative attractiveness of in-phase and anti-phase patterns. Symmetry breaking of these dynamics can occur via the difference in the natural ...
Di Bello V - - 1995
Aim of this work was to study in a group of elite cyclists, undergoing laboratory testing, the trend of the left ventricular systolic and diastolic function, echocardiographically and Doppler derived, simultaneously with the evaluation of ergospirometric parameters during maximal exercise. We studied a group of male subjects, consisting of 10 ...
Schneider A J - - 1995
OBJECTIVE: The medical practitioner is faced with an increasing list of protocols and algorithms related to patient care. These recommendations are often difficult to recall, particularly in stressful emergency situations. Using advanced cardiac life support (ACLS) protocols, we built a computer-based system to exhibit precompiled response plans for medical emergencies. ...
Kondo C - - 1995
BACKGROUND: Excellent results regarding mortality are well recognized in the long-term period after intracardiac repair of tetralogy of Fallot. However, it is still unclear how postoperative sequelae affect cardiac performance during exercise. METHODS AND RESULTS: Twenty-nine patients with tetralogy of Fallot were studied 16 +/- 2 years after intracardiac repair ...
Vantrimpont P J - - 1995
The purpose of the study was to evaluate whether infusion of a beta-adrenergic agonist, prior to and during exercise, could compensate for reduced sympathetic stimulation and correct deficient acceleration of left ventricular relaxation, so preventing a rise in left ventricular filling pressures during exercise after cardiac transplantation. Abnormal left ventricular ...
de Paola A A - - 1995
To verify the prognostic value of exercise induced ventricular arrhythmias in patients with chagasic cardiomyopathy. 69 consecutive patients (37 male, 32 female; age range 21-67 years) with chronic chagasic cardiomyopathy and ventricular arrhythmias (more than 10 ventricular premature complexes per hour) were evaluated during treadmill exercise testing, using the Bruce ...
Noh C I - - 1995
OBJECTIVE: To emphasize the importance of ventricular tachycardia associated with repolarisation abnormality in syncope associated with exercise. DESIGN: Retrospective analysis of data on children presenting with syncope between 1985 and 1993. PATIENTS: 5 apparently normal children with recurrent exercise related syncope associated with electrocardiographically abnormal TU complexes. RESULTS: 3 children ...
Li L - - 1995
AIM: To study the effects of osthole (Ost) on the isolated guinea pig atria and the relationship between Ost effect and Ca2+. METHODS: Contractions of left atria were induced by electric stimulations. The contractile amplitude of left atria pre- and post-treated with Ost was measured according to the cumulative concentration ...
Kyriakides Z S - - 1995
There is controversy over the effects of beta-blockade on the left ventricular systolic response of the heart of the elderly to stress. In this study we compared the effects of acute beta-blockade in normal older and younger adult left ventricles during exercise. The study population consisted of 17 healthy elderly ...
Berntsen R F - - 1995
The majority of patients with serious ventricular arrhythmias induced by exercise have ischemic heart disease. These arrhythmias, however, develop only in a minority of the patients with coronary artery disease. The aim of this study was to investigate whether patients with ventricular tachycardia or fibrillation produced by exercise-induced ischemia exhibit ...
Dahan M - - 1995
OBJECTIVES: This study evaluated the role of preload reserve in the stroke volume response to exercise in patients with left ventricular systolic dysfunction by assessing the relation between stroke volume and late left ventricular diastolic filling during exercise. BACKGROUND: In patients with left ventricular diastolic dysfunction, the absence of left ...
Nass R - - 1995
The effects of 6 months of replacement therapy with recombinant human GH (hGH) on physical work capacity and cardiac structure and function were investigated in 20 patients with hGH deficiency of adult onset in a double blind, placebo-controlled trial. The GH dose of 12.5 micrograms/kg BW was self-administered daily sc. ...
Nash M S - - 1995
The purposes of the study were (1) to characterize left ventricular wall motion, and the cardiodynamic and metabolic responses during electrical stimulation cycle ergometry (ESCE) exercise in tetraplegic people; (2) to test whether these responses linger into the post-exercise recovery period; and (3) to test whether they differ from those ...
Duncker D J - - 1995
This study was carried out to test the hypothesis that alpha 1-adrenergic activation during exercise causes preferential vasoconstriction of subepicardial coronary resistance vessels, thereby augmenting blood flow to the subendocardium. Studies were performed in 7 dogs in which left ventricular hypertrophy was produced by banding the ascending aorta at 6-9 ...
Walls J - - 1995
Recombinant human erythropoietin (r-HuEPO) treatment reduces cardiac output and increases left ventricular mass: beneficial effects that might be expected to be maximized at near-normal haemoglobin values. Quality of life in dialysis patients treated with r-HuEPO has been shown to be related to haemoglobin, up to a haematocrit of 35%. The ...
Wirth A - - 1995
The aim of this work was to compare left ventricular performance during weight reduction induced by either physical training and diet or diet alone. Forty-three moderately obese subjects received a hypocaloric diet of 800 kcal/d for 4 weeks; 22 of them were also subjected to an exercise program. By means ...
Jurić M - - 1995
The aim of our study was to evaluate cardiovascular function at rest and during exercise in dialysis patients before and after treatment with Epo and to examine the changes in left ventricular mass as the consequence of treatment for anaemia. We applied echocardiography and radionuclide ventriculography at rest and after ...
Lehman C D - - 1995
PURPOSE: To determine the type and prevalence of prenatal ultrasound (US) findings in fetuses with trisomy 13. MATERIALS AND METHODS: Prenatal US findings in 33 consecutive fetuses with trisomy 13 and in 200 karyotypically normal fetuses were reviewed and compared. RESULTS: One or more abnormalities were found in 30 fetuses ...
Palatini P - - 1995
The aim of the study was to examine the effect of chronic angiotensin converting enzyme inhibition on haemodynamics and left ventricular performance during long-lasting exercise at the anaerobic threshold. For this purpose exercise haemodynamics and left ventricular performance were assessed in 14 physically trained hypertensives (aged 26 y) before and ...
Taki J - - 1994
The cardiac functional response to exercise in patients with nonobstructive hypertrophic cardiomyopathy (HCM) was evaluated using a continuous ventricular function monitor with a cadmium telluride detector (CdTe-VEST). METHODS: Supine ergometric exercise was performed under CdTe-VEST monitoring in 41 patients with nonobstructive HCM (34 men and 7 women, age 18-72 yr, ...
Van Tosh A - - 1994
Transient dilatation of the left ventricular cavity on exercise thallium perfusion imaging is recognized as a marker of significant coronary disease, but the mechanisms that produce this finding are not fully understood. We studied 32 patients who underwent exercise thallium imaging and exercise echocardiography to determine the changes in left ...
LeJemtel T H - - 1994
BACKGROUND: Peak oxygen consumption is reduced in patients with symptomatic congestive heart failure, but functional capacity of patients with asymptomatic left ventricular systolic dysfunction has not been assessed by measurement of peak oxygen consumption attained during graded exercise testing. METHODS AND RESULTS: Peak oxygen consumption, that is, aerobic capacity (VO2, ...
Walker J D - - 1994
Medical management of patients with chronic left ventricular dysfunction continues to be a difficult problem. Recent clinical and experimental studies have suggested that 3,5,3'-triiodo-L-thyronine improves left ventricular pump function. However, whether 3,5,3'-triiodo-L-thyronine directly improves myocyte contractile function in cardiomyopathic states is unknown. Accordingly, this study examined the direct effects of ...
Gledhill N - - 1994
Left ventricular function was examined during incremental work rates to maximum using simultaneous determinations of stroke volume, left ventricular ejection time (LVET), and diastolic filling time (DT). Seven endurance trained and seven untrained young adult males were studied on a cycle ergometer at matched heart rates of 90, 120, 140, ...
Billman G E - - 1994
alpha-Adrenergic receptor responsiveness has been reported to increase during myocardial ischemia, correlating with onset of malignant arrhythmias. If alpha-adrenoceptor mechanisms play a significant role in induction of life-threatening arrhythmias, inhibition of these receptors with specific alpha-adrenoceptor antagonists should protect against disturbances in cardiac rhythm. To test this hypothesis, we induced ...
Tsai CL - - 1994
Evaluation of eye-hand coordination skills in relation to experiential human factors may lead to improved instruction for videoendoscopic surgical skills acquisition. Twenty-nine subjects (medical students or residents in surgical specialties) volunteered to perform three exercises of increasing complexity in an "inanimate" trainer system that simulated the eye-hand coordination tasks inherent ...
Semigran M J - - 1994
OBJECTIVES: This study was undertaken to determine whether abnormalities in exercise capacity or ventricular function persist after recovery from acute dilated cardiomyopathy. BACKGROUND: Persistent ventricular structural abnormalities could cause abnormalities in exercise capacity or ventricular function. METHODS: The results of rest and exercise first-pass radionuclide ventriculography in 18 patients who ...
Lakatta E G - - 1994
In healthy normotensive individuals who have been rigorously screened to exclude coronary disease, the cardiovascular reserve capacity decreases with aging. A reduction in the maximum aerobic capacity is accompanied by a reduction in the maximum heart rate. Stroke volume during vigorous exercise in the upright position does not decline with ...
Percy R F - - 1994
Physiologic variables, such as heart rate, affect the noninvasive indexes of left ventricular filling, complicating the interpretation of these indexes for clinical assessment of diastolic function. We compared the effect in normal subjects of increased heart rate provoked by both exercise and amyl nitrite on noninvasive velocity and volumetric indexes ...
Kimball T R - - 1994
OBJECTIVES: The purposes of this study were to evaluate left ventricular performance and contractility at rest and during exercise to determine mechanisms and correlates for alterations in performance and blood pressure in pediatric patients after successful repair of coarctation of the aorta. BACKGROUND: Blood pressure and left ventricular function are ...
Braun L T - - 1994
Endurance exercise requires that the heart maintain a highly elevated cardiac output for an extended period of time, working against a slightly elevated afterload. Endurance athletes manifest a large ventricular volume, characterized on echocardiogram by an increased end-diastolic internal diameter and wall thickness. This article describes the structural, functional, and ...
Sneddon J F - - 1994
Five cases of exercise induced pure vasodepressor syncope in patients without significant structural heart disease are reported. Hypotension and symptoms of syncope or pre-syncope were induced by treadmill exercise testing and in each case limited exercise performance. Evidence of inappropriate peripheral vasodilation, probably as a consequence of ventricular mechanoreceptor stimulation, ...
Kaplan J D - - 1994
The hemodynamic factors contributing to reduced exercise capacity in adults with congenital heart disease are not fully defined. We hypothesized that they would demonstrate reduced exercise capacity compared with age-matched control subjects because of abnormal exercise hemodynamics and ventricular performance demonstrable by echocardiography. We retrospectively analyzed the results of all ...
Seals D R - - 1994
This review describes age-related changes in autonomic control of the circulation during exercise and the associated effects on exercise capacity. The increase in heart rate during exercise becomes smaller with aging probably due to both less withdrawal of cardiac vagal tone and diminished beta-adrenergic responsiveness. The latter also appears to ...
Soria F - - 1994
OBJECTIVES: To investigate whether cardiovascular performance can be modified beneficially with left ventricular hypertrophy reversal and whether the associated sudden afterload increases may adversely affect overall cardiac performance. METHODS: We studied cardiovascular performance with thermodilution techniques at rest and during maximal treadmill exercise after 3 weeks' treatment with the angiotensin ...
Yoshida J - - 1994
Hemodynamic parameters during supine leg exercise-induced myocardial ischemia were investigated in ten patients without left ventricular hypertrophy (group I), and in ten patients with left ventricular hypertrophy (group II). Both groups of patients had previously been diagnosed as having totally asymptomatic silent myocardial ischemia. Both groups were comparable in age, ...
Handy J R - - 1994
Acute postoperative left ventricular dysfunction after hypothermic, crystalloid potassium cardioplegia occasionally occurs. This project examined myocyte contractility and inotropic responsiveness after hypothermic arrest with and without potassium cardioplegia. Isolated swine left ventricular myocytes were placed in a thermostatically controlled chamber (37 degrees C) that contained a standard cell medium, pulse ...
Gratama J W - - 1994
To compare hemodynamic changes induced by isoproterenol and exercise stress tests in individuals with and without left ventricular volume load, we studied 10 lambs with an aortopulmonary shunt [58 +/- 4% (SE) of left ventricular output] 2 wk after the shunt was created. Two studies, isoproterenol infusion at 0.1 microgram.kg-1.min-1 ...
Tomita T - - 1994
BACKGROUND: The effects of chronic exercise training on myocardial contractility and beta-adrenergic signal transduction in hearts with left ventricular dysfunction have not been determined. METHODS AND RESULTS: Fourteen-week-old cardiomyopathic BIO 53.58 and normal F1B Syrian hamsters underwent 10 weeks of treadmill training and were compared with 24-week-old BIO 53.58 and ...
Sutton M G - - 1994
Three patients (age 18-39 years; two men) with normal exercise capacity, normal left ventricular function, large muscular false tendons within the left ventricle, and anomalously placed papillary muscles associated with giant T wave inversion on the electrocardiogram are described. The absence of adverse cardiovascular events at long-term follow up (mean ...
Taki J - - 1994
Left ventricular function during exercise and recovery was investigated in patients with angina pectoris, ST segment depression during exercise and angiographically normal coronary arteries (syndrome X) using a continuous left ventricular function monitor with cadmium telluride detector (CdTe-VEST). Fourteen patients with syndrome X and 14 patients with atypical chest pain ...
Genovesi-Ebert A - - 1994
OBJECTIVE: To investigate the possible association between Doppler left ventricular filling pattern and exercise capacity in a group of normotensives to severe hypertensive patients. BACKGROUND: Invasive left ventricular filling indexes evaluated at rest are reported to be related to exercise capacity in heart failure. Whether exercise capacity is limited by ...
Søgaard P - - 1994
Patients with acute or chronic heart disease may have limited exercise capacity if they have reduced left ventricular function. Indexes of reduced left ventricular function during exercise are a predictor of subsequent survival although left ventricular ejection fraction is a poor predictor of physical endurance. We evaluated the effect of ...
Kawachi K - - 1994
The exercise hemodynamics of eight patients who underwent cardiac catheterization were assessed at rest and during exercise, before and after left ventricular aneurysmectomy by the classical technique. Left ventricular end-diastolic volume increased before operation and then significantly decreased after the operation (p < 0.05). The ejection fraction increased from 0.27 ...
Erez M - - 1994
Ventricular fibrillation (VF) is a major cause of sudden cardiac death in humans. Currently used antiarrhythmic drugs are aimed at preventing initiation of VF by decreasing the incidence of arrhythmias which can lead to VF. This approach today seems to be insufficient. On the basis of reports that VF can ...
Iwasaka T - - 1994
To evaluate the effects of gender and isometric handgrip exercise on left ventricular diastolic function in normal individuals, atrial and rapid filling fraction were investigated using M-mode echocardiography in 35 postmenopausal women and 31 age-matched men. There were no significant differences in heart rate, mean blood pressure, atrial filling fraction, ...
Jaski B E - - 1993
OBJECTIVES: The goal of this study was to assess patients with end-stage heart disease after implantation of a left ventricular assist device at rest and during exercise compatible with activities of daily life. BACKGROUND: Mechanical circulatory assistance with a left ventricular assist device is an accepted therapy for bridging patients ...
Berntsen R F - - 1993
The role of myocardial revascularization in the treatment of malignant ventricular arrhythmias is not well defined. Our hypothesis was that in patients with ventricular tachycardia or fibrillation exposed by exercise-induced ischaemia, the acute transient ischaemia plays a principal causal role, and that in these patients surgical myocardial revascularization alone might ...
< 2 3 4 5 6 7 8 9 10 11 12 >