Search Results
Results 601 - 650 of 1031
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Riecanský I - - 2001
Before and immediate (invasive examination) and long-term follow-up (4.5 year; echocardiography, exercise electrocardiography) studies after percutaneous transvenous mitral valvuloplasty (PTMV; Inoue technique) were prospectively performed in 123 consecutive patients with pure or dominant mitral stenosis. These patients consisted of two groups: Group A with suitable valve morphology (n = 108, ...
Little W C - - 2000
Tachycardia accompanying exercise shortens the duration of diastole, reducing the time available for the left ventricular (LV) filling. Thus, the LV must fill more rapidly for the stroke volume to increase (or even be maintained) during exercise. Normally, this is accomplished without requiring an excessive increase in left atrial (LA) ...
Le Tourneau T - - 2000
OBJECTIVES: The purpose of this study was to prospectively investigate the effects of surgical correction of mitral regurgitation (MR) on exercise performance, cardiac function and neurohormonal activation. BACKGROUND: Little is known about the effect of surgical correction of MR on functional status or on neurohormonal activation. METHODS: Cardiopulmonary exercise test, ...
Spina R J - - 2000
To determine whether endurance exercise training can alter the beta-adrenergic-stimulated inotropic response in older women, we studied 10 postmenopausal healthy women (65.4 +/- 0.9 yr old) who exercised for 11 mo. Left ventricular (LV) function was evaluated with two-dimensional echocardiography during infusion of isoproterenol after atropine. Maximal O(2) consumption increased ...
Scognamiglio R - - 2000
In this study we assess the mechanisms of exercise-induced left ventricular (LV) dysfunction in asymptomatic patients with Type 1 diabetes mellitus (T1DM) without coronary artery disease. Fourteen patients and 10 volunteers were enrolled. LV volume, LV ejection fraction (LVEF) and end-systolic wall stress were calculated by two-dimensional echocardiography at rest ...
Nilsson I L - - 2000
BACKGROUND: Nontraditional manifestations of primary hyperparathyroidism (HPT) are controversial and may include morbidity, mortality, and risk factors for cardiovascular diseases. This study evaluates cardiovascular functions at rest and during exercise in HPT. METHOD: Thirty patients with HPT (mean serum calcium, 2.97 +/- 0.24 mmol/L) and 30 control people with normocalcemia, ...
Pibarot P - - 2000
This study examines the resting and exercise hemodynamic performance of the pulmonary autografts in the aortic position as well as of the homografts used for right ventricular outflow reconstruction in patients undergoing the Ross operation. Previous studies have reported excellent resting hemodynamics in patients who underwent aortic valve replacement with ...
Thomas D P - - 2000
Whether or not exercise training of sufficient intensity and duration to produce left ventricle (LV) hypertrophy also regulates deposition of interstitial collagen and cross-linking at the pretranslational level is unknown. Therefore, the effects of exercise training on gene expression for the two principal fibrillar collagens in LV, types I and ...
Becassis P - - 2000
OBJECTIVES: The objective of this study was to determine whether a small-size valve prosthesis contributes to exercise intolerance, as assessed by VO2 measurement during an exhaustive cycle ergometer exercise. BACKGROUND: The determinants of exercise capacity after mechanical aortic replacement are not well known. The selection of small valve sizes has, ...
Libonati J R - - 2000
PURPOSE: Left ventricular (LV) diastolic function is an important determinant of aerobic fitness. The purpose of this paper was to investigate the relationship between aerobic fitness and the rate and extent of isovolumic LV relaxation. METHODS: Two series of experiments were performed utilizing both human and animal models. In the ...
Zuo P - - 2000
BACKGROUND: The impaired adrenergic control of both inotropic and lusitropic reserves has been evaluated in patients with hypertrophic cardiomyopathy (HCM) but not in those with apical HCM (APH). OBJECTIVES: We examined the influence of increases in heart rate and adrenergic stimulation on inotropic and lusitropic reserves in HCM and APH ...
Rhodes J - - 2000
Although exercise testing is commonly employed to identify adult aortic regurgitation (AR) patients with early left ventricular (LV) dysfunction, the role and value of exercise testing in the management of pediatric AR patients have not been established. The purposes of this study were to evaluate the cardiorespiratory response to exercise ...
Poulsen S H - - 2000
BACKGROUND: Left ventricular (LV) diastolic function predicts and correlates with exercise capacity. Beta-blockers improve exercise capacity and LV diastolic function in patients with severe LV systolic dysfunction in dilated cardiomyopathy. However, information on the effect of metoprolol XL on exercise capacity in relation to LV diastolic function in patients with ...
Hambrecht R - - 2000
CONTEXT: Exercise training in patients with chronic heart failure improves work capacity by enhancing endothelial function and skeletal muscle aerobic metabolism, but effects on central hemodynamic function are not well established. OBJECTIVE: To evaluate the effects of exercise training on left ventricular (LV) function and hemodynamic response to exercise in ...
Tanabe Y - - 2000
BACKGROUND: Percutaneous transvenous mitral commissurotomy (PTMC) results in short-term hemodynamic and symptomatic improvements. We have previously shown that the immediate symptomatic relief is related to the improvement in excessive exercise ventilation. The exercise capacity, however, does not improve in the short term but does improve gradually over several months. The ...
Florea V G - - 2000
BACKGROUND: We studied the direction and magnitude of changes in left ventricular (LV) cavity size and mass over time and whether these changes were related to those in exercise performance in patients with chronic heart failure (CHF). METHODS AND RESULTS: The study group was composed of 59 patients (55 men ...
Sekiguchi K - - 2000
To evaluate the effects of left ventricular (LV) dysfunction upon the sympathetic nervous and renin-aldosterone-angiotensin systems, neurohormonal factors were measured in patients with ischemic heart disease. Eleven patients were divided into two groups by their LV ejection fraction based on previous catheterization; preserved (EF > or = 60%) and impaired ...
Borghetti V - - 2000
OBJECTIVE: The effects of different annuloplasty rings on mitral annulus dynamics and left-ventricular (LV) function after mitral-valve repair (MVR) are still controversial. This study sought to compare biological versus prosthetic rigid rings for annular remodelling in MVR at long term. METHODS: Forty-four consecutive patients were retrospectively enrolled. All patients had ...
Okura H - - 2000
BACKGROUND: Doppler-derived left ventricular (LV) diastolic indexes have been shown to correlate with exercise capacity in patients with heart diseases as well as healthy individuals. However, it is uncertain whether they predict exercise capacity independent of noncardiac factors. METHODS: To clarify the impact of the LV diastolic index on exercise ...
Fries R - - 2000
BACKGROUND: The hemodynamic superiority of stentless valves at rest has been generally accepted, but there is a lack of studies on exercise hemodynamics. METHODS: We assessed aortic valve hemodynamics at rest and during exercise in 10 patients with a 23-mm stentless aortic bioprosthesis (Medtronic Freestyle; Medtronic Europe SA/NV, St. Stevens ...
Kröger K - - 2000
PURPOSE: We measured changes in peak systolic velocity ratio and sonogaphic vascular diameter during different hemodynamic conditions in patients with femoral or iliac artery stenosis. METHODS: In 35 patients with isolated femoral or iliac artery stenosis, prestenotic and intrastenotic peak systolic velocity and inner vascular diameter were calculated using color ...
Poirier P - - 2000
Patients with type 2 diabetes often have impaired exercise capacity compared with nondiabetic subjects. Left ventricular (LV) diastolic dysfunction has been shown to limit exercise performance in nondiabetic subjects. Men with well-controlled type 2 diabetes were divided into 2 groups: normal LV diastolic function (group 1, n = 9) or ...
Suman O E - - 2000
To determine whether strength-trained individuals with physiological concentric left ventricular (LV) hypertrophy exhibit enhanced inotropic responses to catecholamines, we studied 11 bodybuilders, aged 33.0 +/- 2 (SE) yr old, and 10 sedentary healthy subjects, aged 31.3 +/- 2.4 yr old, at baseline and during infusion of incremental doses of dobutamine ...
Battle R W - - 2000
BACKGROUND: Several investigators have studied the effects of exercise on pressure gradients and valve area measurements in patients with senile calcific aortic stenosis. However, there are limited data on young patients with congenital aortic stenosis. The current study was conducted to assess the dynamic effect of exercise on aortic valve ...
Yamagishi M - - 2000
An 8-year-old girl who weighed 42 kg presented Ebstein's anomaly with severe tricuspid incompetence, and mild systemic cyanosis during exercise. A new reconstructive procedure for this complex anomaly was used. Oblique transference of the displaced posterior leaflet was performed, which resulted in plication of the atrialized ventricle and reduction in ...
Woodiwiss A J - - 2000
Habitual exercise results in a rightward shift in left ventricular end diastolic (LVED) pressure-volume or internal dimension (P-D) relationships [left ventricular (LV) remodeling]. However, exercise-mediated LV hypertrophy (LVH) produces an increased LV relative wall thickness [ratio (h/r) of wall thickness (h) to internal radius (r)] and hence a decrement in ...
van Wachem P B - - 2000
Calcification limits the long-term durability of xenograft glutaraldehyde-crosslinked heart valves. In this study, epoxy-crosslinked porcine aortic valve tissue was evaluated after subcutaneous implantation in weanling rats. Non-crosslinked valves and valves crosslinked with glutaraldehyde or carbodiimide functioned as control. Epoxy-crosslinked valves had somewhat lower shrinkage temperatures than the crosslinked controls, and ...
Nellessen U - - 2000
BACKGROUND: Hemodynamic improvement is a common finding following valve replacement. However, despite a normally functioning prosthesis and normal left ventricular ejection fraction, some patients may show an abnormal hemodynamic response to exercise. METHODS: In a combined catheter/Doppler study, rest and exercise hemodynamics were evaluated in 23 patients following aortic (n ...
Cuocolo A - - 1999
OBJECTIVE: This study compares the effects of an AT1 angiotensin II receptor antagonist (valsartan) with those of an ACE inhibitor (enalapril) on left ventricular (LV) diastolic function in patients with mild or moderate essential hypertension and no evidence of LV hypertrophy at echocardiography. METHODS: A total of 24 patients (16 ...
Trikas A - - 1999
In patients with primary systemic amyloidosis (AL), the echocardiographic assessment of ventricular function alone does not always correspond to patients' symptoms and functional status. Peak oxygen uptake and anaerobic threshold (AT), in contrast, constitute 2 objective, reliable and reproducible indicators of functional status in patients with circulatory failure. Thirty-two consecutive ...
Pibarot P - - 1999
OBJECTIVES: The objective of this study was to compare stentless bioprostheses with stented bioprostheses with regard to their hemodynamic behavior during exercise. BACKGROUND: Stentless aortic bioprostheses have better hemodynamic performances at rest than stented bioprostheses, but very few comparisons were performed during exercise. METHODS: Thirty-eight patients with normally functioning stentless ...
Molina L - - 1999
The relation between maximum systolic blood pressure (BP) during exercise and left ventricular (LV) mass is controversial. Physical activity also induces LV mass increase. The objective was to assess the relation between BP response to exercise and LV mass in normotensive men, taking into account physical activity practice. A cross-sectional ...
Vanbilloen H P - - 1999
During patient studies with the Technegas equipment in our department, we regularly detected small to considerable contaminations of the operator and in the area surrounding the apparatus. These contaminations were found to be of different origin: residual activity in the tubing from the apparatus to the patient which diffuses after ...
Nagueh S F - - 1999
OBJECTIVES: The purpose of this study was to evaluate changes in left ventricular (LV) filling, left atrial (LA) volumes and function six months after nonsurgical septal reduction therapy (NSRT) for hypertrophic obstructive cardiomyopathy (HOCM). BACKGROUND: Patients with HOCM frequently have enlarged left atria, which predisposes them to atrial fibrillation. Nonsurgical ...
Porter G F - - 1999
BACKGROUND AND AIMS OF THE STUDY: The Ross procedure, in which the aortic valve is replaced with the patient's own pulmonary valve (pulmonary autograft), is considered an excellent alternative for younger patients requiring elective aortic valve replacement. Although resting pulmonary autograft hemodynamics are excellent, exercise hemodynamic data are lacking. The ...
Strike P C - - 1999
BACKGROUND AND AIMS OF THE STUDY: Exercise treadmill testing was used to evaluate the functional rest and stress hemodynamic profile of the Medtronic Intact aortic bioprosthesis. METHODS: A group of 93 patients (mean age at operation 72.9 years; range: 61-79 years) was studied. Mean time to follow up was 20.8 ...
González-Juanatey J R - - 1999
OBJECTIVE: To determine the haemodynamic behaviour, at rest and during exercise, of aortic valve pericardial bioprostheses and different sizes of bileaflet prosthesis. DESIGN: Observational study. SETTING: Tertiary medical centre. PATIENTS AND INTERVENTIONS: 74 patients (33 women, 41 men; mean age 64 years) in whom 40 pericardial bioprostheses and 34 bileaflet ...
Briguori C - - 1999
Some studies have demonstrated that left ventricular (LV) diastolic function is the principal determinant of impaired exercise capacity in hypertrophic cardiomyopathy (HC). In this study we sought the capability of echocardiographic indexes of diastolic function in predicting exercise capacity in patients with HC. We studied 52 patients with HC while ...
Foster C - - 1999
PURPOSE: Interval training (INT) is a commonly used method of exercise training in both athletic and clinical populations. Although we generally understand left ventricular (LV) function during steady state (SS) exercise, there are no data regarding LV function during INT. METHODS: We studied eight healthy, physically active volunteers during upright ...
Barlow C W - - 1999
BACKGROUND AND AIMS OF THE STUDY: The study aim was to examine the effects of balloon mitral valvotomy (BMV) on exercise-induced hyperkalemia, and on changes in the concentration of Na,K-pumps in skeletal muscle, as an exaggerated exercise-induced rise in potassium concentration ([K+]) may contribute to exertional fatigue and breathlessness. METHODS: ...
Rinder M R - - 1999
BACKGROUND: Endurance exercise training can increase left ventricular (LV) ejection fraction during dynamic exercise in coronary artery disease. This adaptation may be mediated by altered cardiac loading conditions rather than an improvement in intrinsic LV systolic function. To minimize these confounding effects, we used isometric handgrip exercise to assess the ...
Digenio A G - - 1999
PURPOSE: Based on reports that patients with severe left ventricular (LV) dysfunction have a greater ventilatory response to effort than healthy people, we evaluated the ventilatory responses to effort of patients with coronary artery disease and various degrees of LV impairment before and after 6 months of exercise training in ...
Di Lenarda A - - 1999
OBJECTIVES: The purpose of this study was to analyze whether long-term treatment with the nonselective beta-adrenergic blocking agent carvedilol may have beneficial effects in patients with dilated cardiomyopathy (DCM), who are poor responders in terms of left ventricular (LV) function and exercise tolerance to chronic treatment with the selective beta-blocker ...
Eriksson M J - - 1999
Temporal variability and reproducibility of Doppler-derived variables obtained during supine symptom-limited exercise was investigated in 26 patients who were in clinically and hemodynamically stable condition with normally functioning nonstented aortic bioprostheses (stentless porcine, n = 13; cryopreserved homografts, n = 13). All patients had normal systolic left ventricular function and ...
Bossone E - - 1999
OBJECTIVES: The aim of this study was to explore the full range of tricuspid valve regurgitation velocity (TRV) at rest and with exercise in disease free individuals. Additionally we examined the relationship of stroke volume (SV), cardiac output (CO) and TRV to exercise capacity. BACKGROUND: Doppler evaluation of TRV can ...
Whyte G - - 1999
Early echocardiographic studies of left ventricular (LV) morphology and function focused on single discipline athletes, primarily endurance and strength trained. To date there are few studies examining multi-disciplinary trained athletes. The present echocardiographic study examined LV morphology and function in 18 elite triathletes (swimming, cycling, and running) and 11 elite ...
Duncker D J - - 1999
When exercise in the presence of a coronary artery stenosis results in subendocardial ischemia, administration of a nitric oxide (NO) donor increases subendocardial blood flow, whereas NO synthesis blockade worsens subendocardial hypoperfusion. Because left ventricular hypertrophy (LVH) is also associated with subendocardial hypoperfusion during exercise, this study tested the hypothesis ...
Rinaldi C A - - 1999
BACKGROUND: Myocardial stunning is known to occur following a single episode of effort angina in patients with coronary artery disease. The effect on left ventricular (LV) function of repeated episodes of ischaemia is unknown. OBJECTIVES: To investigate the effects of repeated episodes of exercise induced ischaemia on LV function in ...
Lapu-Bula R - - 1999
Although exercise intolerance is a cardinal symptom of patients with dilated cardiomyopathy (DC) and heart failure, the factors that limit exercise capacity in these patients remain a matter of debate. To assess the contribution of left ventricular (LV) diastolic filling to the variable exercise capacity of patients with DC, we ...
Marwick T H - - 1999
OBJECTIVES: The aim of this study was to evaluate whether preoperative clinical and test data could be used to predict the effects of myocardial revascularization on functional status and quality of life in patients with heart failure and ischemic LV dysfunction. BACKGROUND: Revascularization of viable myocardial segments has been shown ...
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