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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cheyne-Stokes respiration is known to be associated with severe left heart failure. Because of severe desaturation, sleep fragmentation, arousals, and an increase in sympathetic activity, Cheyne-Stokes respiration may lead to a further impairment of cardiac function and to a worsening of quality of life. Although the pathology of Cheyne-Stokes respiration is not fully understood, enhanced chemoreceptor sensitivity, prolonged circulation time, as well as decreased pulmonary gas stores and increased ventilatory drive may be contributing factors. Therapeutic options include the improvement of cardiac failure; medical treatment, such as using theophylline; continous positive airway pressure ventilation; and low-flow oxygen supply. Because of severe cardiac insufficiency, change of endothoracic pressure may worsen the hemodynamic situation in some patients. Therefore, this form of treatment has to be used carefully. Another possible treatment is a low-flow oxygen supply, which will prevent severe desaturations. This therapeutic approach might be a good alternative to noninvasive ventilation. However, it is controversial whether oxygen supply will improve quality of sleep of the patients, even in long-term treatment.
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PMID:Sleep-Breathing Disorders and Heart Failure. 1186 27

Patients suffering from severe heart failure may develop breathing pattern disorders during sleep, especially in the form of Cheyne-Stokes respiration. Results may be severe disturbances in sleep architecture and worsening of hemodynamics and of prognosis of these patients. Causes of the periodic breathing disorders are probably hypocapnia, hypersensitivity of respiratory control centers, hypoxemia, and prolonged blood circulation time. This study examined the influence of different concentrations of continously administered oxygen during the nighttime on breathing pattern disorders, oxygen saturation, and sleep architecture in 65 patients with severe heart failure (NYHA III-IV). Fifty-two of 65 patients showed an improvement of sleep architecture. Total sleeping time increased significantly (p < 0.01). Fragmentations of sleep by arousals decreased ( p < 0.01); time of random eye movement (REM) sleep and non-REM sleep III and IV increased significantly.
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PMID:Influence of Low-Flow Oxygen Supply on Sleep Architecture in Patients with Severe Heart Failure (NYHA III-IV) and Cheyne-Stokes Respiration. 1186 28

Nasal continuous positive airway pressure therapy has recently been studied as a nonpharmacologic adjunct to congestive heart failure therapy. In patients with congestive heart failure, it was reported that continuous positive airway pressure therapy for the condition Cheyne-Stokes respiration with central sleep apnea led to long-term improvements in cardiac function and alleviation of heart failure symptoms. Cheyne-Stokes respiration with central sleep apnea is a frequent breathing disorder well described in patients with congestive heart failure, and is an associated risk factor for increased cardiovascular morbidity and mortality. These apneas cause an increase in sympathetic nervous system activity, which would maintain afterload at a high level or tend to increase it with time, leading to further compromise of ejection fraction. Continuous positive airway pressure appears to benefit the failing heart by increasing intrathoracic pressure, which is believed to cause an increase in cardiac output by decreasing the pressure gradient across the heart wall and allowing the left-ventricular end diastolic volume to decrease, thereby reducing the afterload. This beneficial "resting" of the heart has been documented to increase left-ventricular ejection fraction, increase cardiac index, improve inspiratory muscle strength, lower blood pressure and heart rate, decrease plasma and overnight urinary levels of norepinephrine, lower levels of atrial natriuretic peptide and endothelin-1, and increase heart rate variability. Other benefits include improvement in New York Heart Association functional class status and improvement in dyspnea.
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PMID:Congestive heart failure and continuous positive airway pressure therapy: support of a new modality for improving the prognosis and survival of patients with advanced congestive heart failure. 1197 41

Chronic cardiac failure is often associated with sleep respiratory disorders. These abnormalities are often unrecognised and represent a marker of the severity of cardiac failure and carry a poor prognosis. The mechanism of apnoea is either central, resulting in periodic nocturnal Cheyne-Stokes respiration, or peripheral by obstruction of the upper respiratory tract. Both mechanisms may be observed in the same patient. Oxygen desaturation, fragmentation of sleep and inspiratory depression lead to sympathetic activation and an increase in let ventricular afterload which can aggravate the cardiac failure. Treatment by continuous positive pressure with a nasal mask can help some patients. It is therefore important to diagnoses these nocturnal disorders using simplified polysomnographic recordings.
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PMID:[Heart failure and respiratory sleep disorders]. 1205 69

Patients with chronic congestive cardiac failure (CCF) frequently suffer from central sleep apnoea syndrome (CSAS). Continuous positive airway pressure (CPAP) has been suggested as a treatment. The authors hypothesised that bilevel ventilation might be easier to initiate and superior to CPAP at correcting the sleep-related abnormality of breathing in patients with CCF. After excluding those with a history suggestive of obstructive sleep apnoea, 35 patients with CCF (left ventricular ejection fraction <35%) were screened with overnight oximetry and the diagnosis of CSAS was established with polysomnography in 18. Two 14-day cycles of CPAP (0.85 kPa (8.5 mbar)) or bilevel ventilation (0.85/0.3 kPa (8.5/3 mbar)) in random order, were compared in a crossover study. Sixteen patients (13 males), mean age 62.0+/-7.4 yrs completed the study. The pretreatment apnoea/hypopnoea index of 26.7+/-10.7 was significantly reduced by CPAP and bilevel ventilation to 7.7+/-5.6 and 6.5+/-6.6, respectively. The arousal index fell from 31.1+/-10.0 per hour of sleep to 15.7+/-5.4 and 16.4+/-6.9, respectively. Significant and equal improvements with CPAP and bilevel ventilation were found for sleep quality, daytime fatigue, circulation time and New York Heart Association class. The authors conclude that continuous positive airway pressure and bilevel ventilation equally and effectively improve Cheyne-Stokes respiration in patients with congestive cardiac failure.
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PMID:Assisted ventilation for heart failure patients with Cheyne-Stokes respiration. 1241 86

Recent epidemiologic studies indicate that approximately 40 to 50% of stable patients with congestive heart failure (CHF) suffer from either obstructive sleep apnea (SA) or Cheyne-Stokes respiration with central SA. In either type of sleep apnea, several mechanisms contribute to significant mechanical and adrenergic stresses upon the failing myocardium. These include hypoxemia, reductions in intrathoracic pressure, rises in systemic arterial pressure, increases in left ventricular afterload, and arousals from sleep worsening the sleep architecture. Consequently, sympathetic activation and parasympathetic withdrawal are the hallmark of sleep-related sleeping disorders that contribute to the progression of heart failure and may adversely affect its prognosis. On the other hand, recent studies indicate that successful treatment of either type of SA with continuous positive airway pressure in patients with CHF results in objective and subjective improvement in the severity of heart failure increases in left ventricular ejection fraction, and reductions in sympathetic nervous system activity. Therefore, the early diagnosis and specific treatment of either obstructive or central SA in patients with CHF is highly warranted.
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PMID:Cardiovascular implications of sleep apnea in patients with congestive heart failure. 1244 40

Obstructive sleep apnoeas are common among stroke patients and, as different from central apnoeas, they do not decline during stroke rehabilitation. Cerebral and cardiovascular changes display a different pattern during central and obstructive sleep apnoeas. The cerebral blood flow velocity according to transcranial Doppler increases during an obstructive apnoea and decreases after apnoea termination concomitant with changes in arterial pressure. The changes in cerebral circulation during obstructive apnoeas could be an immediate effect of rapid changes in blood pressure because cerebral autoregulation is overridden. Low cerebral blood flow, low arterial pressure and hypoxemia after apnoea termination may predispose to nocturnal cerebral ischaemia. The opposite pattern is seen during a central apnoea, with a decrease in cerebral blood flow velocity during apnoea and an increase after apnoea termination. Changes during obstructive apnoeas are probably hazardous, with adverse cardiovascular effects including stroke. This may not be the case during central apnoeas, as Cheyne-Stokes respiration with central apnoeas is a result of an underlying disorder such as heart failure and stroke and is not a disease entity in itself. It is suggested that obstructive sleep apnoea is a risk factor for stroke as it is common among stroke victims and cerebral hypoperfusion occurs after an obstructive apnoea. The treatment of sleep apnoea should also be taken into account among stroke patients. Large cohort studies, treatment studies and further studies of possible mechanisms for apnoea-induced stroke are, however, essential in order to evaluate whether obstructive sleep apnoea is an independent risk factor for stroke.
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PMID:Cerebral haemodynamics in obstructive sleep apnoea and Cheyne-Stokes respiration. 1250 76

In patients with congestive heart failure, Cheyne-Stokes respiration is accompanied by oscillations in blood pressure and heart rate at a very low frequency. It is not known whether these cardiovascular oscillations are primarily related to oscillations in ventilation or oxyhemoglobin saturation. We hypothesized that abolition of the ventilatory oscillations of Cheyne-Stokes respiration by CO2 inhalation would eliminate accompanying oscillations in blood pressure and heart rate but that elimination of hypoxic dips by supplemental O2 would not. We studied 10 subjects with heart failure and Cheyne-Stokes respiration during sleep using frequency spectral analysis. During Cheyne-Stokes respiration, heart rate and blood pressure oscillated in association with respiratory oscillations at very low frequency. Inhalation of CO2 abolished Cheyne-Stokes respiration and associated oscillations in both blood pressure and heart rate. In contrast, inhalation of O2 sufficient to eliminate hypoxic dips had no significant effect on Cheyne-Stokes respiration, blood pressure (n = 6), or heart rate (n = 5). We conclude that ventilatory oscillations during Cheyne-Stokes respiration rather than oscillations in oxygenation per se powerfully induce heart rate and blood pressure oscillations. Cheyne-Stokes respiration is therefore one of the mechanisms that contributes to the very low-frequency oscillations in heart rate and blood pressure observed in patients with heart failure.
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PMID:Influence of Cheyne-Stokes respiration on cardiovascular oscillations in heart failure. 1262 47

Cheyne-Stokes respiration, a breathing pattern found in patients with heart failure, is characterized by periodic changes in ventilation. This pattern of breathing is also associated with oscillations in the arousal state, blood oxygen level, carbon dioxide blood level, and the blood pressure. Although originally described as an irregular breathing pattern or an unstable breathing pattern, Cheyne-Stokes respiration may be quite stable for prolonged periods of time. This breathing pattern may represent a clinical disorder in which disease results in a low-frequency oscillation of the system. Treatment that either reduces or abolishes the oscillation results in clinical improvement because of reduced oscillation of the systems whose function is linked to the changes in ventilation.
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PMID:Cheyne-Stokes respiration: Stability of interacting systems in heart failure. 1277 24

Heart failure is associated with Cheyne-Stokes breathing, which fragments patients' sleep. Correction of respiratory disturbance may reduce sleep fragmentation and excessive daytime sleepiness. This randomized prospective parallel trial assesses whether nocturnal-assist servoventilation improves daytime sleepiness compared with the control. A total of 30 subjects (29 male) with Cheyne-Stokes breathing (mean apnea-hypopnea index 19.8 [SD 2.6] and stable symptomatic chronic heart failure (New York Heart Association Class II-IV) were treated with 1 month's therapeutic (n = 15) or subtherapeutic adaptive servoventilation. Daytime sleepiness (Osler test) was measured before and after the trial with change in measured sleepiness the primary endpoint. Secondary endpoints included brain natriuretic peptide levels and catecholamine excretion. Active treatment reduced excessive daytime sleepiness; the mean Osler change was +7.9 minutes (SEM 2.9), when compared with the control, the change was -1.0 minutes (SEM, 1.7), and the difference was 8.9 minutes (95% confidence interval, 1.9-15.9 minutes; p = 0.014, unpaired t test). Significant falls occurred in plasma brain natriuretic peptide and urinary metadrenaline excretion. We conclude that adaptive servoventilation produces an improvement in excessive daytime sleepiness in patients with Cheyne-Stokes breathing and chronic heart failure. This study suggests improvements in neurohormonal activation with this treatment.
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PMID:A randomized controlled trial of adaptive ventilation for Cheyne-Stokes breathing in heart failure. 1292 10


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