Biomedical subjects

Klaus K A Witte

Publications and source records attributed to Klaus K A Witte.

At least 19 recordsLinked to original sources

PubMed2006

Effects of applying a standardised management algorithm for moderate to severe renal dysfunction in patients with chronic stable heart failure.

BACKGROUND: No specific guidelines exist on how to manage renal dysfunction (RD) in patients with chronic heart failure (CHF). AIMS: To identify the proportion of patients with moderate to severe RD and CHF who showed an improvement in their renal function in response to a systematic management algorithm. METHODS: Stable patients with CHF and RD (defined by a serum creatinine (SCr) of >130 micromol/l (>1.5 mg/dl)) were enrolled into a systematic management algorithm. The following changes were implemented: switching aspirin to clopidogrel, halving the dose of both diuretics and angiotensin converting enzyme (ACE) inhibitors and switching between bisoprolol and carvedilol. RESULTS: Two thirds of patients in whom diuretics were reduced, and one fifth of patients in whom ACE inhibitors were reduced, improved their SCr by >25.5 micromol/l (0.3 mg/dl). All these changes were more marked in the presence of bilateral renal artery stenosis. Compared to a reference group, in whom no changes were implemented, the treatment group showed an improvement in their mean SCr by 35 micromol/l (0.4 mg/dl), p<0.001. CONCLUSION: Manipulation of pharmacological therapy for patients with CHF and RD results in a substantial recovery of renal function in a minority of patients.

Aged↗

PubMed2006

Anemia, renal dysfunction, and their interaction in patients with chronic heart failure.

Anemia and renal dysfunction (RD) are frequent complications seen in chronic heart failure (HF). However, the prevalence and interaction of these co-morbidities in a representative population of outpatients with chronic HF is poorly described. In this study, it was sought to determine the association between RD and anemia in patients with HF enrolled in a community-based HF program. Nine hundred fifty-five patients with HF due to left ventricular systolic dysfunction were investigated for the prevalence of anemia and its cause and followed for a median of 531 days. Anemia was defined as hemoglobin < 12.0 g/dl in women and < 13.0 g/dl in men. RD was defined as a calculated glomerular filtration rate of < 60 ml/min. The prevalence of anemia was 32%. Fifty-three percent of patients with and 27% of those without anemia had > or = 1 test suggesting hematinic deficiency. The prevalence of RD was 54%. Forty-one percent of patients with and 22% of patients without RD had anemia, with similar proportions associated with iron deficiency in the presence or absence of RD. Anemia and RD independently predicted a worse outcome, and this effect was additive. In conclusion, in outpatients with chronic HF, anemia and RD are common and co-exist but confer independent prognostic information. A deficiency of conventional hematinic factors may cause about 1/3 of anemia in this clinical setting.

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PubMed2006

Left ventricular morphology, global and longitudinal function in normal older individuals: a cardiac magnetic resonance study.

BACKGROUND: The heart transforms structurally and functionally with age but the nature and magnitude of reported changes appear inconsistent. This study was designed to assess left ventricular (LV) morphology, global and longitudinal function in healthy older men and women using cardiac magnetic resonance (CMR). METHODS: Ninety-five healthy subjects (age 62+/-16 years, range 22-91 years) underwent breath-hold cine CMR. LV end-diastolic volume (EDV), end-systolic volume (ESV), myocardial mass, ejection fraction (EF), mass-to-volume ratio, mean midventricular wall motion, thickness and thickening were calculated from short-axis data sets. Average mitral annular displacement was measured to assess longitudinal LV function. RESULTS: Subjects were divided according to age (< 65 and > or = 65 years) and sex. EDV and ESV indices (corrected for body surface area) decreased whilst EF increased with age. There was no difference in LV myocardial mass index between the age groups, but midventricular wall thickness was significantly higher in older people. Mass-to-volume ratio also increased with age. In contrast to EF, mitral annular displacement declined with age. Midventricular LV wall thickness, myocardial mass index and mass-to-volume ratio were higher in men than in women but there were no differences in measures of global and longitudinal LV systolic function. CONCLUSIONS: Due to smaller LV volumes but higher wall thickness, myocardial mass remains unchanged with age. We have found an age-related increase in EF and reduction in longitudinal LV function in apparently normal subjects. This must be borne in mind when assessing older patients with possible heart failure and normal LV systolic function. Men have higher myocardial mass than women.

Adult↗

PubMed2006

The effect of altering heart rate on ventricular function in patients with heart failure treated with beta-blockers.

BACKGROUND: Beta-blockers are effective for the treatment of heart failure, but their mechanism of action is unresolved. Heart rate reduction may be a central mechanism or a troublesome side effect. METHODS: A randomized, double-blind, parallel group study comparing chronic higher-rate (80 pulses per minute) with lower-rate (60 pulses per minute) pacing in pacemaker-dependent patients with symptomatic left ventricular (LV) systolic dysfunction, receiving beta-blockers. Gated radionuclide ventriculography (RNVG) was performed at baseline and after at least 9 months. The primary outcome was change in LV volumes, as a marker of beneficial reverse remodeling, from baseline to follow-up. RESULTS: Forty-nine patients were randomized. Mean age was 74 +/- 6 years and with LV ejection fraction of 26% +/- 9% at baseline. During 14 +/- 13 months of follow-up, 21 patients (43%) died and 25 (51%) completed the study protocol: 12 in the higher-rate and 13 in the lower-rate group. Mean LV end-diastolic (higher rate +20 +/- 104 mL vs lower rate -65 +/- 92 mL, P = .03) and systolic (higher rate +29 +/- 83 mL vs lower rate -60 +/- 74 mL, P = .006) volumes increased with higher-rate versus lower-rate pacing, whereas LV ejection fraction declined (higher rate -4.2% +/- 4.4% vs lower rate +2.2% +/- 5.4%, P = .002). CONCLUSION: Reversal of beta-blocker-induced bradycardia has deleterious effects on ventricular function, suggesting heart rate reduction is an important mediator of their effects. The prognosis of patients with pacemakers and heart failure is poor.

Adrenergic beta-Antagonists↗

PubMed2006

Biventricular pacemaker upgrade in previously paced heart failure patients--improvements in ventricular dyssynchrony.

BACKGROUND: Cardiac resynchronization therapy (CRT) reduces symptoms and mortality in patients with left bundle branch block (LBBB) and severe chronic heart failure. There are few data demonstrating the effects of CRT on contemporary dyssynchrony variables in patients with advanced heart failure who have been chronically paced from the right ventricle (RV). METHODS AND RESULTS: We reviewed baseline and follow-up clinical and echocardiographic data on patients receiving CRT in a single centre. Indices of global left ventricular (LV) function and dyssynchrony before and after CRT were measured. Patients were then divided into those receiving their first device (n = 39) and those receiving CRT as an upgrade to existing RV pacemakers (n = 32). Baseline demographic variables, indices of global LV function, symptomatic status, renal function, hemodynamics, and diuretic requirements were not different between previously paced patients and nonpaced patients. Mean length of RV pacing in the previously paced patients was 59 months (range 12-167 months). Patients in the previously paced group had a broader QRS complex than patients with intrinsic LBBB. Aortopulmonary delay of longer than 40 ms was present in 68% of all subjects, 67% had intraventricular septal and posterior wall motion delay longer than 130 ms, and 59% had an intraventricular delay as measured by tissue Doppler imaging of longer than 65 ms. There was no difference between paced and nonpaced patients for any of these measures of dyssynchrony. QRS duration was reduced to a greater extent in the previously paced patients than those with no previous device therapy. CRT led to important reductions in each dyssynchrony variable in both patients with previous RV pacing and those with intrinsic LBBB. The magnitude of these changes in measures of dyssynchrony was not different between the 2 groups. In all patients undergoing CRT, 50% had a reduction in furosemide dose at 3 months, 56% an improvement of at least 1 grade in New York Heart Association status, and 66% an improvement of at least 5% in LVEF. Divided by group, previously paced patients were no more or less likely than newly implanted patients to achieve one or more of these clinical outcomes. CONCLUSION: Our data suggest that patients with RV pacing and heart failure have similar dyssynchrony as patients with intrinsic LBBB. CRT leads to improvements in LV global function, dyssynchrony variables and symptoms in patients chronically paced from the RV that are similar to those observed in patients with LBBB without preexisting devices.

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PubMed2005

Incidence of renal dysfunction over 6 months in patients with chronic heart failure due to left ventricular systolic dysfunction: contributing factors and relationship to prognosis.

AIMS: To determine the prevalence and incidence of renal dysfunction (RD) in patients with chronic heart failure (CHF), to identify contributory factors and predictors of worsening renal function (WRF), and to explore the relationship between RD and mortality. METHODS AND RESULTS: Prospective data on 1216 patients with CHF were analysed. The glomerular filtration rate (GFR) was used to determine renal function, and WRF was defined as an increase in serum creatinine of >26.5 micromol/L (>0.3 mg/dL). The prevalence of RD defined as a GFR of <60 mL/min was 57%. During 6 months, WRF occurred in 161 (13.0%) patients. Predictors of WRF were vascular disease, the use of thiazide diuretics, and a baseline urea >9 mmol/L. Two hundred and sixty-three (21.6%) patients died, and baseline RD and WRF both predicted a higher mortality (P<0.001), whereas an improvement in renal function over the first 6 months predicted a lower mortality (hazard ratio 0.8, 95% confidence interval 0.6-1.0). CONCLUSION: In ambulatory patients with CHF, RD is common, commonly deteriorates over a relatively short period of time, is unlikely to recover substantially, and augurs a poor prognosis.

Adult↗

PubMed2005

Metabolic gas kinetics depend upon the level of exercise performed.

BACKGROUND: The kinetics of oxygen and carbon dioxide at the onset of and recovery from exercise are slowed in patients with chronic heart failure (CHF). The aim of the present study was to establish whether the kinetics of O2 are influenced by the work rate. METHODS: Thirteen CHF patients and 12 control subjects underwent bicycle-based peak exercise testing with metabolic gas exchange analysis. Each subject then exercised at 15%, 25% and 50% of the maximal workload achieved until reaching steady state. Time constants for onset (T(onset)) and offset (T(offset)) for O2 uptake and CO2 output were correlated to the workload and the percentage of peak V(O2) performed during the steady state tests. RESULTS: Patients had lower peak oxygen uptake (pV(O2)) and the relation between ventilation and carbon dioxide output was steeper in patients than controls. T(offset) for both oxygen (O2) and carbon dioxide (CO(2)) from peak exercise was significantly greater in the patients than the controls and correlated with peak V(O2) (r=0.56, p<0.005 and r=0.58, p<0.005). T(onset) and T(offset) for O2 were increased in patients for each of the steady state tests and peak V(O2) correlated with T for recovery of O2 (r=0.44; p<0.05 from 15%, r=0.35; p= or <0.05 from 25%, and r=0.54; p<0.01 from 50%). There was a correlation between the T(onset) (r=0.42; p<0.0005 for O2 and r=0.23; p<0.05 for CO2) and T(offset) (r=0.49; p<0.0001 for O2 and r=0.42; p<0.0005 for CO2) and oxygen uptake as a percentage of peak exercise. CONCLUSIONS: This study demonstrates that the time constants of onset and offset for oxygen are dependent upon the degree of exertion performed relative to the individual's peak capacity.

Blood Gas Analysis↗

PubMed2005

The effect of micronutrient supplementation on quality-of-life and left ventricular function in elderly patients with chronic heart failure.

AIMS: Chronic heart failure (CHF) is a common and leading cause of death in industrialized countries. The potential benefits of micronutrient supplementation in CHF are extensive. Therefore, we examined the influence of long-term multiple micronutrient supplementation on left ventricular (LV) function, levels of pro-inflammatory cytokines, and quality-of-life (QoL) in elderly patients with CHF. METHODS AND RESULTS: Thirty CHF patients [age 75.4 (0.7), mean (SEM), LV ejection fraction (LVEF) < or =35%] were randomized to receive capsules containing a combination of high-dose micronutrients (calcium, magnesium, zinc, copper, selenium, vitamin A, thiamine, riboflavin, vitamin B(6), folate, vitamin B(12), vitamin C, vitamin E, vitamin D, and Coenzyme Q10) or placebo for 9 months in a double-blind fashion. All subjects were on stable optimal medical therapy for at least 3 months before enrolment. At randomization and at study end, tumour necrosis factor-alpha and its soluble receptors TNFR-1 and TNFR-2 were measured and six-minute walk test and QoL were assessed. Cardiac magnetic resonance scanning was performed to evaluate cardiac dimensions and LVEF. Two patients died during follow-up. The remaining patients (14 randomized to placebo and 14 to micronutrients) were well matched for LV function, symptoms, and exercise capacity. At the end of the follow-up period, LV volumes were reduced in the intervention group with no change in the placebo group [-13.1 (17.1)% vs. +3.8 (10.0)%; P<0.05]. LVEF increased by 5.3+/-1.4% in the intervention group and was unchanged in the placebo group (P<0.05). Patients taking micronutrients also had a significant improvement in QoL score between enrolment and study end [+9.5 (1.6)%; P<0.05], whereas those taking placebo had a slight deterioration [-1.1 (0.8)%; P=0.12]. Six-minute walk test and inflammatory cytokine levels remained unchanged in both groups. CONCLUSION: Long-term multiple micronutrient supplementation can improve LV volumes and LVEF and QoL scores in elderly patients with heart failure due to LV systolic dysfunction.

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PubMed2005

The effect of ventricular pacing on measurements of left ventricular function: a comparison between echocardiographic methods and with radionuclide ventriculography.

AIMS: Different methods exist for measuring left ventricular function echocardiographically; each may be error prone due to the abnormal pattern of ventricular activation during pacing. METHODS AND RESULTS: Echocardiography was undertaken on 307 patients with permanent pacemakers; a subset of 57 underwent radionuclide ventriculography. Intrinsic and paced beats were analysed for left ventricular function by: Simpson's bi-plane, Teicholz M-mode, wall-motion scoring and 'eyeball' assessment. Agreement between techniques and with radionuclide ventriculography were compared according to intrinsic or paced beats. Echocardiographic measures of ejection fraction give mean values 5% higher than radionuclide ventriculography (Simpson's 30+/-9%, vs. Teicholz 30+/-13% vs. radionuclide ventriculography 25+/-9%, p=0.03). Agreement between Simpson's, Teicholz and radionuclide ventriculography by Bland-Altman analysis showed poor agreement (Simpson's vs. Teicholz range (4xSD)=57%, Simpson's vs. radionuclide ventriculography=36%, Teicholz vs. radionuclide ventriculography=46%, p=0.02), the level of agreement deteriorates with ventricular pacing (Simpson's vs. Teicholz range=61%, Simpson's vs. radionuclide ventriculography=34%, Teicholz vs. radionuclide ventriculography=47%, p=0.02). The correlation between wall motion analysis and radionuclide ventriculography is moderately poor (all subjects r=0.58, ventricular pacing r=0.52, not pacing r=0.66). CONCLUSION: Echocardiography and radionuclide ventriculography are the only non-invasive techniques to assess left ventricular function in the paced population. Results are poorly interchangeable and the accuracy of any comparison dependent on the underlying rhythm.

Echocardiography↗

PubMed2005

Longitudinal myocardial dysfunction in healthy older subjects as a manifestation of cardiac ageing.

BACKGROUND: Abnormalities of longitudinal left ventricular (LV) contraction and relaxation may be early markers of cardiac disease. This study was designed to assess the relationship between long-axis LV function and age in healthy subjects. METHODS: 118 healthy individuals aged 57 +/-19 years (range 20-90 years) with no evidence of cardiovascular disease under-went echocardiography with Doppler examination of transmitral flow. To assess longitudinal LV function, systolic (S(m)), early diastolic (E(m)) and late diastolic (A(m)) mitral annular velocities were measured using colour-coded tissue Doppler imaging. RESULTS: The left atrium was enlarged (P<0.001) in subjects >/=60 years of age compared to those <60 years, but there were no differences in LV volumetric indices and ejection fraction. Peak E velocity was lower (P<0.001) and peak A velocity of transmitral flow was higher in older subjects (P<0.001) with a higher E/A ratio (P<0.001) and longer isovolumic relaxation time (P= 0.001) indicative of impaired ventricular relaxation. S m and E m mitral annular velocities decreased (P<0.001) and A m velocity increased (P=0.002) in the older group. E m velocity and E m /A m ratio showed a strong negative correlation with age (r= -0.80, P<0.001 and r=-0.78, P<0.001, respectively). CONCLUSIONS: Global LV systolic function is preserved but the velocity of long-axis systolic shortening is depressed in older individuals, indicating selective impairment of the longitudinal component of systolic contraction. The decline in the velocity of early diastolic long-axis LV lengthening and the changes in the pattern of transmitral flow suggest impaired ventricular relaxation. These measures of cardiac function may be a useful index of normal cardiac ageing.

Adult↗

PubMed2005

Deployment of left ventricular lead from the ipsilateral side of central vein obstruction.

Cardiac resynchronisation therapy improves symptoms and reduces mortality in patients with chronic heart failure. In patients with previously implanted devices, particularly automatic defibrillators, central venous stenoses provide a challenge to upgrading to resynchronisation devices. We present a patient with central venous obstruction secondary to previously implanted defibrillator leads, in whom we achieved coronary sinus pacing through the ipsilateral internal jugular vein.

Aged↗

PubMed2005

Beta-blockers and inspiratory pulmonary function in chronic heart failure.

BACKGROUND: Chronic heart failure (CHF) patients complain of breathlessness and fatigue. Respiratory muscle function is impaired in CHF patients and may contribute to their symptoms. Beta-blockers cause fatigue but have become part of the standard management of CHF. We explored the relation between respiratory muscle power in CHF and the effects of long-term beta-blockade. METHODS AND RESULTS: A total of 52 CHF patients and 25 control subjects underwent echocardiography, peak exercise testing with metabolic gas exchange analysis, and measurement of forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak inspiratory flow (PIF), and forced inspiratory volume in 1 second (FIV1). Of the patients, 35 started beta-blocker therapy and were tested again at 1 year. Patients had lower peak oxygen consumption (pV(O2) (19.3 [4.5] versus 37.3 [8.4] mL/kg/min, P < .0001), exercise time (414 [134] versus 817 [193] seconds, P < .0001), and anaerobic threshold (13.8 [3.8] versus 27.2 [8.2] mL/kg/min, P < .0001). Patients also had a steeper relationship between ventilation (V(E)) and carbon dioxide (CO2 ) (V(E)/V(CO2)) (40.0 [6.8] versus 26.4 [2.0], P < .0001); lower FEV1, FVC, and FIV1 (89 [15] versus 111 [24]% expected, P < .0001, 80 [20] versus 94 [21]% expected, P < .001 and 2.5 [1.6] versus 3.0 (0.9) L, P < .02); and there was a correlation between pV(O2) and FIV1 (r = 0.24, P < .05) for the patients. The slope relating symptoms of breathlessness (Borg score) to ventilation (Borg/V(E) slope) also correlated with FIV1 (r = 0.36, P < .02). Beta-blocker therapy improved echocardiographic variables, but not pV(O2). There was no change in PIF or FIV1. There was a significant reduction in FEV 1 after beta-blocker treatment (P < .01). CONCLUSION: Inspiratory flows are impaired in patients with chronic heart failure and correlate with the degree of functional impairment. This may be due to a combination of respiratory muscle weakness and reduced lung compliance. The reduction in inspiratory capacity is not influenced by long-term beta-blockade.

Adrenergic beta-Antagonists↗

PubMed2005

The effects of long-term beta-blockade on the ventilatory responses to exercise in chronic heart failure.

AIMS: Chronic heart failure (CHF) patients complain of breathlessness and fatigue. Beta-blockers improve symptoms, echocardiograpahic variables and prognosis in CHF, but their effect on exercise capacity remains unclear. The aim of this study was to describe the effects of long-term beta-blocker therapy on metabolic gas exchange variables and ventilation during exercise in CHF patients. METHODS: 42 patients with symptomatic heart failure due to left ventricular systolic dysfunction (ejection fraction 33.2 (8.2)) on loop diuretics and angiotensin-converting enzyme inhibitors or angiotensin II antagonists, underwent exercise testing with metabolic gas exchange. They were then initiated onto and uptitrated to the maximum tolerated dose of beta-blockers. After 1 year of follow-up, patients were invited back for repeat testing. RESULTS: 35 patients attended for repeat exercise testing. Four patients had died, and three had not tolerated beta-blockade. After 1 year, exercise time was increased (487 (221) vs. 500 (217), p<0.05), and peak oxygen consumption and V(E)/V(CO(2)) slope were unchanged (20.9 (5.0) vs. 20.0 (5.4), p=0.15 and 36.7 (8.3) vs. 37.3 (7.8), p=0.70). Peak ventilation, (61.5 (12.9) vs. 57.1 (13.4), p<0.05), peak carbon dioxide production (1629 (404) vs. 1496 (375), p<0.02) and hence respiratory exchange ratio (1.02 (0.08) vs. 0.98 (0.06) p<0.02) and p<0.05) were reduced. Submaximal oxygen consumption and carbon dioxide production were lower at matched workloads. The slope relating symptoms to ventilation (Borg/V(E) slope) was less steep following beta-blockade (0.18 (0.09) vs. 0.15 (0.06), p<0.05). CONCLUSION: Long term beta-blocker therapy increases exercise time but not peak oxygen consumption, and reduces peak carbon dioxide production. CHF patients are less symptomatic for a given ventilation during exercise following beta-blocker treatment.

Adrenergic beta-Antagonists↗

PubMed2005

Chronic heart failure and multiple micronutrient supplementation: realistic hope or idealistic conjecture?

Recent studies have demonstrated the inefficacy of nutritional supplements containing various combinations of vitamins and minerals for otherwise healthy elderly people and patients with ischemic heart disease. However, patients with chronic heart failure (CHF) have, up until recently, been excluded from such studies. CHF has a high mortality and morbidity and patients are often elderly with poor general nutrition and high levels of micronutrient deficiency. It is in this population that nutritional supplementation has the most potential benefit. Evidence is accumulating that a strategy of long-term highdose multiple micronutrient supplementation might improve symptoms and cardiac function in elderly patients with CHF. In this article, we review the effects of individual micronutrients and how they might impact on CHF, and present recent data that dietary supplementation might offer an addition to standard therapy for CHF.

Dietary Supplements↗

PubMed2004

Application of tissue Doppler imaging in cardiology.

Tissue Doppler imaging (TDI) is a new echocardiographic technique employing the Doppler principle to measure the velocity of myocardial segments and other cardiac structures. It is well suited for the measurement of long-axis ventricular function. Impairment of longitudinal myocardial fiber motion is a sensitive marker of early myocardial dysfunction and ischaemia, and TDI might therefore become an important tool in routine echocardiography. The technique allows truly quantitative measurement of regional myocardial function both at rest and during stress echocardiography. TDI has great potential in the diagnosis of diastolic left ventricular dysfunction, overcoming the load-dependence of conventional Doppler techniques. Right ventricular function, intracardiac and pulmonary artery pressures, transplant rejection and intraventricular dyssynchrony can also be assessed. This article reviews the current and evolving applications of TDI in cardiology.

Animals↗

PubMed2004

Are hematinic deficiencies the cause of anemia in chronic heart failure?

BACKGROUND: Anemia in chronic heart failure (CHF) is common, varying in prevalence between 14.4% and 55%, and is more frequent in patients with more severe heart failure. Patients with CHF who have anemia have a poorer quality of life, higher hospital admission rates, and reduced exercise tolerance. We explored the relation between hematinic levels and hemoglobin (Hb) levels and exercise tolerance in a group of patients with CHF. METHODS: We analyzed data from 173 patients with left ventricular systolic dysfunction (LVSD), 123 patients with symptoms of heart failure, but preserved left ventricular (LV) systolic function ("diastolic dysfunction"), and 58 control subjects of similar age. Each underwent echocardiography, a 6-minute walk test, and blood tests for renal function and Hb and hematinic levels (vitamin B12, iron, and folate). We classified patients as having no anemia (Hb level >12.5 g/dL), mild anemia (Hb level from 11.5-12.5 g/dL), or moderate anemia (Hb level <11.5 g/dL). RESULTS: Of patients with LVSD, 16% had moderate anemia and 19% had mild anemia. Of patients with preserved LV function, 16% had moderate anemia and 17% had mild anemia. Four control subjects had a Hb level <12.5 g/dL. Of all patients, 6% were vitamin B12 deficient, 13% were iron deficient, and 8% were folate deficient. There was no difference between patients with LVSD and the diastolic dysfunction group. In patients with LVSDS, the average Hb level was lower in New York Heart Association class III than classes II and I. The distance walked in 6 minutes correlated with Hb level in both groups of patients with CHF (r = 0.29; P <.0001). Patients with anemia achieved a lower pVO2 (15.0 [2.3] vs 19.5 [4.4], P <.05). Peak oxygen consumption correlated with Hb level (r = 0.21, P <.05) in the patients, but not in the control subjects. In patients with anemia, the mean creatinine level was higher than in patients with a Hb level >12.5 g/dL, but there was no clear relationship with simple regression. Hematocrit level and mean corpuscular volume were not different in the patients with diastolic dysfunction, patients with LV dysfunction, or the control subjects. Hematocrit levels were not influenced by diuretic dose. Patients with anemia were not more likely to be hematinic deficient than patients without anemia. CONCLUSIONS: Patients with symptoms and signs of CHF have a high prevalence of anemia (34%) whether they have LV dysfunction or diastolic dysfunction, but few patients have hematinic deficiency. Hemoglobin levels correlate with subjective and objective measures of severity and renal function.

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PubMed2004

The reversibility of increased airways resistance in chronic heart failure measured by impulse oscillometry.

BACKGROUND: Patients with chronic heart failure complain of breathlessness and fatigue on exercise. Airways resistance is increased and lung compliance is reduced in chronic heart failure patients. The aim of this study was to determine whether the pulmonary abnormalities are reversible and whether any improvements lead to changes to exercise capacity or symptoms. METHODS: Twelve patients with stable chronic heart failure and 10 matched controls underwent repeated assessment of airways resistance using impulse oscillometry and peak exercise testing with metabolic gas exchange after receiving nebulized saline as placebo or combined salbutamol and ipratropium bromide in a double-blind crossover randomized fashion. RESULTS: Patients had lower peak oxygen consumption and a steeper slope relating ventilation to carbon dioxide production than controls. Bronchodilators reduced peripheral airways resistance in patients (0.53 versus 0.38, P<.02) and controls (0.21 versus 0.19, P<.005) and increased measures of compliance in both groups. There was no effect on the peak oxygen consumption, exercise time, ventilation to carbon dioxide slope, or anaerobic threshold. There was an increase in peak tidal volume (VT) in both groups but this did not lead to an increase in peak ventilation. The slope relating symptoms to ventilation (ie, Borg/VE) was significantly reduced in the patients after bronchodilators (17%+/-8%, P<.05). The relationship between the improvement in VT and reduction in gradient of the Borg/VE slope was significant (r=.40, P<.05). CONCLUSIONS: Nebulized bronchodilators improve airways resistance, lung reactance, and peak tidal volume during exercise in chronic heart failure but do not increase peak exercise capacity. They do, however, reduce the symptom of breathlessness.

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PubMed2004

The effect of aspirin on the ventilatory response to exercise in chronic heart failure.

INTRODUCTION: Patients with chronic heart failure (CHF) experience breathlessness and fatigue on exercise. One of the abnormalities seen on maximal exercise testing is an increased ventilatory response to exercise (VE/VCO(2) slope). The cause of this is unknown, but is likely to be due to a combination of interacting peripheral and central factors. Recent data have demonstrated a relation between VE/VCO(2) slope and prostaglandin levels in contracting muscles. The present study examined the influence of the presence of a potent non-selective prostaglandin inhibitor, aspirin, on the ventilatory response to exercise in a group of patients with CHF. METHODS: We investigated the ventilatory response to exercise of 120 consecutive patients in sinus rhythm attending a specialist heart failure clinic. We excluded those taking clopidogrel (six patients) and those on both warfarin and aspirin or taking other non-steroidal anti-inflammatory agents (five patients). The other 109 patients were grouped according to whether they were taking aspirin (n=52 (48%)) or not (n=57 (52%)). Each patient underwent echocardiography to assess left ventricular function, and exercise testing with metabolic gas exchange to derive peak oxygen consumption (pVO(2)) and the VE/VCO(2) slope. RESULTS: The groups were similar in terms of age, (67 (13) vs. 66 (12) years; P=0.34) drug use, heart failure aetiology, left ventricular function (ejection fraction; 33.3 (9.4) vs. 31.8 (9.9)%; P=0.05)) and exercise tolerance (pVO(2); 20.4 (5.3) vs. 19.9 (6.0); P=0.68, and VE/VCO(2) slope; 35.4 (6.2) vs. 35.7 (9.3); P=0.73). There was no difference in the ventilatory response to exercise or the symptoms of breathlessness between the two groups. CONCLUSIONS: Aspirin does not appear to affect exercise performance in CHF.

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