Bi-level positive airway pressure ventilation for treating heart failure with central sleep apnea that is unresponsive to continuous positive airway pressure.

BACKGROUND: Cheyne-Stokes respiration with central sleep apnea (CSR-CSA) is associated with a poor prognosis in patients with heart failure (HF). However, some patients do not respond to continuous positive airway pressure (CPAP), so other therapeutic modalities should be considered, such as bi-level positive airway pressure (PAP), which also assists respiration and might be effective for such patients. METHODS AND RESULTS: The 20 patients with HF because of left ventricular systolic dysfunction were assessed: 8 had ischemic etiology, and all had severe CSA according to the apnea - hypopnea index (AHI) determined by polysomnography. All diagnosed patients underwent repeat polysomnography using CPAP. The AHI improved significantly in 11 (AHI <15), but only slightly in 9, in whom the AHI remained high (>or=15). Bi-level PAP titration significantly improved the AHI in the latter group. Those who were unresponsive to CPAP had significantly lower PaCO(2), higher plasma brain natriuretic peptide (BNP), longer mean duration of CSR and fewer obstructive episodes than CPAP responders. After 6 months of positive airway support with either CPAP (n=9) or bi-level PAP (n=7), BNP levels significantly decreased and left ventricular ejection fraction significantly increased. CONCLUSIONS: Bi-level PAP could be an effective alternative for patients with HF and pure CSR-CSA who are unresponsive to CPAP.     

Primary pulmonary hypertension with central sleep apnea: sudden death after bilevel positive airway pressure therapy

An obese 23-year-old man with sleep-disordered breathing and primary pulmonary hypertension (PPH) had been administered oral beraprost sodium, anticoagulant warfarin, and home oxygen therapy, at another hospital as treatment for the PPH, but he had not experienced any symptomatic improvement. The patient had a body mass index of 32.4kg/m2, and complained of fatigue, shortness of breath on exertion, excessive daytime sleepiness, and snoring. Arterial blood gas analysis showed a PaO2 and a PaCO2 of 70.9 and 31.2mmHg, respectively. A polysomnographic study revealed central sleep apnea with an apnea-hypopnea index (AHI) of 29.7episodes/h. The patient showed improvement of daytime sleepiness after starting nocturnal nasal bilevel positive airway pressure (BiPAP) therapy for the central sleep apnea, but his pulmonary hypertension, measured in the daytime, worsened. The patient died suddenly while walking to the bathroom in the morning 1 month after initiation of BiPAP therapy. It is necessary to consider the possibility of sudden death when nasal BiPAP therapy is given to a PPH patient with central sleep apnea.     

Effect of nasal continuous positive airway pressure on sleep apnea in congestive heart failure

We studied five patients with chronic stable congestive heart failure (CHF), all of whom demonstrated recurrent apneas in association with Cheyne-Stokes respiration (CSR) during sleep. All five patients had symptoms consistent with a sleep apnea syndrome. Nasal continuous positive airway pressure (NCPAP) was administered at 8 to 12.5 cm H2O to all patients during sleep. The number of apneas fell from (mean +/- SE) 60 +/- 12/h of sleep on the control night to 9 +/- 7/h of sleep (p less than 0.01) on the NCPAP night, whereas mean nocturnal SaO2 rose from 88 +/- 2% on the control night to 92 +/- 2% (p less than 0.025) while on NCPAP. This was associated with resolution of symptoms of sleep apnea. In addition, resting left ventricular ejection fraction (LVEF) as measured by radionuclide angiography (RNA) rose from 31 +/- 8% while off NCPAP to 38 +/- 10% (p less than 0.05) while on NCPAP. Furthermore, all five patients experienced marked improvement in symptoms of heart failure from functional classes III and IV (New York Heart Association Classification) prior to NCPAP therapy to class II after NCPAP therapy was instituted. We conclude that, in certain patients, CSR during sleep associated with chronic CHF constitutes a sleep apnea syndrome, which can be alleviated by NCPAP. In addition, NCPAP therapy may lead to a reduction in cardiac dyspnea and improvement in left ventricular function.     

BiPAP呼吸机治疗充血性心力衰竭临床观察

目的：观察双水平正压通气（BiPAP）呼吸机治疗充血性心力衰竭（CHF）的临床疗效。方法：60例CHF患者被随机分为：BiPAP治疗组（30例），在常规药物治疗的基础上，每天应用BiPAP呼吸机无创通气5～10h，全部用鼻罩；常规治疗组（对照组，30例），常规药物治疗。疗程均为7d。观察两组治疗前后临床疗效、B型利钠肽（BNP）、血气分析、生活质量评分的变化。结果：显效率：BiPAP组73．33％，对照组46．67％，两组有显著差异（P〈0．05）。两组心功能、BNP、血气分析、生活质量评分，治疗后与治疗前相比均有显著差异（P〈0．05～〈0．01），治疗后BiPAP组与对照组间比较有显著差异（P〈0．05～〈0．01）。结论：BiPAP呼吸机不仅能改善CHF患者的通气功能，也能改善CHF患者的心功能，提高患者生活质量。     

Controlled trial of continuous positive airway pressure in obstructive sleep apnea and heart failure

Obstructive sleep apnea (OSA) is highly prevalent among patients with congestive heart failure (CHF) and may contribute to progression of cardiac dysfunction via hypoxia, elevated sympathetic nervous system activity, and systemic hypertension. Our aim was to assess the long-term effect of OSA treatment with nocturnal continuous positive airway pressure (CPAP) on systolic heart function, sympathetic activity, blood pressure, and quality of life in patients with CHF. Fifty-five patients with CHF and OSA were randomized to 3 months of CPAP or control groups. End points were changes in left ventricular ejection fraction, overnight urinary norepinephrine excretion, blood pressure, and quality of life. Nineteen patients in the CPAP group and 21 control subjects completed the study. Compared with the control group, CPAP treatment was associated with significant improvements in left ventricular ejection fraction (delta 1.5 +/- 1.4% vs. 5.0 +/- 1.0%, respectively, p = 0.04), reductions in overnight urinary norepinephrine excretion (delta 1.6 +/- 3.7 vs. -9.9 +/- 3.6 nmol/mmol creatinine, p = 0.036), and improvements in quality of life. There were no significant changes in systemic blood pressure. In conclusion, treatment of OSA among patients with CHF leads to improvement in cardiac function, sympathetic activity, and quality of life.     

Efficacy of nasal bi-level positive airway pressure in congestive heart failure patients with cheyne-stokes respiration and central sleep apnea.

BACKGROUND: Cheyne - Stokes respiration with central sleep apnea (CSR-CSA) contributes to the poor prognosis in patients with congestive heart failure (CHF). Bi-level positive airway pressure (bi-level PAP) may be an effective alternative for treating CSR-CSA and CHF. METHODS AND RESULTS: Fourteen patients with CSR-CSA were divided into 2 groups, a control group that included 7 patients who decided to receive only conventional medications and a group of 7 patients that received bi-level PAP. Left ventricular ejection fraction (LVEF), mitral regurgitation (MR) area, plasma brain natriuretic peptide (BNP) concentration and the New York Heart Association (NYHA) functional class were evaluated initially (baseline) and 3 months later. In the control group, there were no significant changes in cardiac function during the study period. In contrast, in the group that received bi-level PAP, there were significant improvements in LVEF (from 36.3+/-2.9% to 46.0+/-4.0%, p = 0.02), MR area (from 30.4+/-7.6% to 20.0+/-5.1%, p = 0.02), BNP (from 993.6+/-332.0 pg/ml to 474.0+/-257.6 pg/ml, p = 0.02) and NYHA functional class (from 3.1+/-0.1 to 2.1+/-0.1, p = 0.03). CONCLUSION: Treatment with bi-level PAP improved cardiac functions in CHF patients with CSR-CSA.     

Prognosis of patients with heart failure and obstructive sleep apnea treated with continuous positive airway pressure

BACKGROUND: Therapy with continuous positive airway pressure (CPAP) provides several benefits for patients with heart failure (HF) complicated by obstructive sleep apnea (OSA). However, the effect on the prognosis of such patients remains unknown. Aims: To determine whether CPAP therapy and compliance affects the prognosis of HF patients with OSA. METHODS: We classified 88 patients with HF and moderate-to-severe OSA into a CPAP-treated group (n = 65) and an untreated group (n = 23), and then those treated with CPAP were further subclassified according to CPAP therapy compliance. The frequency of death and hospitalization was analyzed using multivariate analysis. RESULTS: During a mean (+/- SD) period of 25.3 +/- 15.3 months, 44.3% of the patients died or were hospitalized. Multivariate analysis showed that the risk for death and hospitalization was increased in the untreated group (hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.07 to 3.68; p = 0.030) and in less compliant CPAP-treated patients (HR, 4.02; 95% CI, 1.33 to 12.2; p = 0.014). CONCLUSION: Therapy with CPAP significantly reduced the risk of death and hospitalization among patients with HF and OSA. However, reduced compliance with CPAP therapy was significantly associated with an increased risk of death and hospitalization.     

Improvement of cheyne-stokes respiration, central sleep apnea and congestive heart failure by noninvasive bilevel positive pressure and medical treatment.

A 57-year-old man was admitted with dyspnea. Clinical evaluation revealed atrial fibrillation and congestive heart failure (CHF). Standard medical therapy of CHF failed to completely improve the dyspnea and polysomnography revealed Cheyne-Stokes respiration with central sleep apnea (CSR-CSA). He was equipped with noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pressure (BiPAP). The combined therapy of medical treatment of the CHF and administration of NPPV with BiPAP reduced the CSR-CSA. This regimen resulted in marked improvement of cardiac function, evaluated by echocardiography, and reduction of plasma concentration of brain natriuretic peptide. After the patient recovered from CHF and was discharged from hospital, he continued to use NPPV with BiPAP at home. In patients with CHF, it is important to be aware of sleep-related breathing disorders because treatment will not only improve the hypoxemia, but also the cardiac dysfunction.     

Hemodynamic effects of bilevel nasal positive airway pressure ventilation in patients with heart failure

AIMS: Benefits of nasal continuous positive airway pressure (CPAP) in patients presenting with chronic heart failure (CHF) are controversial. The purpose of this study was to compare the hemodynamic effects of CPAP and bilevel positive airway pressure (BiPAP) in patients with or without CHF. METHODS AND RESULTS: Twenty patients with CHF and 7 with normal left ventricular function underwent cardiac catheterization. Measurements were made before and after three 20-min periods of BiPAP: expiratory positive airway pressure (EPAP) = 8 cm H2O and inspiratory positive airway pressure (IPAP) = 12 cm H2O, EPAP = 10 cm H2O and IPAP = 15 cm H2O, and CPAP = EPAP = IPAP = 10 cm H2O administered in random order. Positive pressure ventilation decreased cardiac output (CO) and stroke volume. No change was observed in either pulmonary or systemic arterial pressure. There was no difference in the hemodynamic effects of the three ventilation settings. Only mean pulmonary wedge pressure (MPWP) and heart rate were lower with CPAP than with BiPAP. CO decreased only in patients with low MPWP (相似文献   

Sustained effect of continuous positive airway pressure on baroreflex sensitivity in congestive heart failure patients with obstructive sleep apnea

BACKGROUND: Patients with either heart failure or obstructive sleep apnea have a reduced baroreflex sensitivity for heart rate, a sign of poor prognosis. We previously demonstrated that nocturnal application of continuous positive airway pressure to heart failure patients with obstructive sleep apnea increased baroreflex sensitivity acutely, but it is not known whether these effects persist into wakefulness. OBJECTIVE: To determine whether treating obstructive sleep apnea in heart failure patients with continuous positive airway pressure improves baroreflex sensitivity during wakefulness. METHODS: Spontaneous baroreflex sensitivity was assessed during wakefulness in 33 heart failure patients (left ventricular ejection fraction < or = 45%) with obstructive sleep apnea (apnea-hypopnea index > or = 20). Subsequently, baroreflex sensitivity was reassessed 1 month after patients were randomly allocated to nocturnal continuous positive airway pressure treatment or no treatment (control). RESULTS: Compared with the 14 control patients, the 19 continuous positive airway pressure-treated patients experienced a greater increase in baroreflex sensitivity [median, (25%, 75%)] [from 5.4 (2.2, 8.3) to 7.9 (4.4, 9.4) ms/mmHg; P = 0.01] and left ventricular ejection fraction (P < 0.001). In addition, daytime systolic blood pressure and heart rate decreased more in the continuous positive airway pressure group (from 122 +/- 15 to 113 +/- 12 mmHg; P = 0.02, and from 66 +/- 8 to 62 +/- 8 bpm; P < 0.001, respectively) than in the control group. CONCLUSION: Treatment of coexisting obstructive sleep apnea by continuous positive airway pressure in heart failure patients improves baroreflex sensitivity during wakefulness in addition to improving left ventricular ejection fraction and lowering blood pressure and heart rate. These data indicate that the improved autonomic regulation of heart rate in heart failure patients treated for obstructive sleep apnea during sleep persists into wakefulness.     

Continuous positive airway pressure improves nocturnal baroreflex sensitivity of patients with heart failure and obstructive sleep apnea

OBJECTIVES: To determine the acute effects of continuous positive airway pressure (CPAP) on baroreceptor reflex sensitivity (BRS) for heart rate during sleep in congestive heart failure (CHF) patients with obstructive sleep apnea (OSA). DESIGN AND METHODS: In eight CHF patients with OSA not previously treated with CPAP, spontaneous BRS was assessed during overnight polysomnography prior to the onset of sleep, and during stage 2 non-rapid eye movement sleep (NREM) before, during and after application of CPAP. RESULTS: CPAP alleviated OSA and acutely increased the slope of BRS (median, 25%,75%) [from 3.9 (3.5, 4.8) to 6.2 (4.6, 26.2) ms/mmHg, P<0.05]. Increases in the slope of BRS persisted following withdrawal of CPAP [4.9 (4.3, 6.9) ms/mmHg, P<0.05]. CPAP also lowered heart rate (from 81.3 +/- 4.9 to 76.0 +/- 5.7 bpm, P< 0.05), an effect which persisted after its withdrawal (76.7 +/- 5.7 bpm, P < 0.05). Systolic blood pressure at the midpoint of the pressure range of BRS sequences fell while on CPAP (from 139 +/- 8 to 120 +/- 7 mmHg, P < 0.05), and remained lower following CPAP withdrawal (124 +/- 9 mmHg, P < 0.05). CONCLUSIONS: In CHF patients with OSA, CPAP increases acutely BRS during sleep, lowers heart rate and resets the operating point for BRS to a lower blood pressure. These effects of CPAP persist after its withdrawal, suggesting that nocturnal CPAP therapy may cause sustained improvement in the neural control of heart rate.     

Continuous positive airway pressure in heart failure patients with obstructive sleep apnoea

Background: The aim of the study was to study the effect of 6 months of continuous positive airway pressure (CPAP) in community heart failure (HF) patients with obstructive sleep apnoea (OSA). Methods: Clinically stable outpatients with HF and OSA (left ventricular ejection fraction (LVEF) <45%, apnoea/hypopnoea index >15/h, n = 19) treated with CPAP and a control group (LVEF <45%, apnoea/hypopnoea index <10/h, n = 7) were compared at baseline and at 6 months by Minnesota heart failure score, Epworth sleepiness score, shuttle walk distance, brain natriuretic peptide, urinary catecholamines and echocardiographic indices using paired t‐test, McNemar’s tests and effect sizes. Results: In HF patients with OSA, CPAP improved LVEF (35.9 ± 6.1% to 40.6 ± 8.0%, P = 0.015), decreased LV end‐systolic volume (152 ± 74 to 135 ± 62 cm³, P = 0.03), systolic blood pressure (P = 0.04) and sleepiness (Epworth sleepiness score 8.8 ± 4.8 to 6.3 ± 3.2, P = 0.01), whereas walk distance, catecholamines, brain natriuretic peptide levels and symptoms were unchanged. These outcomes did not change in the HF control group. Conclusion: In community HF patients with OSA, CPAP therapy over 6 months improved LVEF, systolic blood pressure and sleepiness, but not sympathetic activation, brain natriuretic peptide or exercise levels. Acceptance was relatively low, potentially limiting therapeutic effectiveness.     

The effects of continuous positive airway pressure on myocardial energetics in patients with heart failure and obstructive sleep apnea.

OBJECTIVES: We sought to examine the short-term and longer term (6-week) effects of continuous positive airway pressure (CPAP) on myocardial energetics. BACKGROUND: Obstructive sleep apnea (OSA) and heart failure (HF) are both states of increased afterload and metabolic demand. Treatment with CPAP may initially reduce stroke volume but subsequently improves left ventricular function. However, it is not clear whether CPAP therapy favorably affects myocardial energetics and hence improves cardiac efficiency. METHODS: Twelve patients with HF were divided into two groups: 7 patients with OSA were treated with CPAP (group I), and 5 patients without OSA served as a control group (group II). Oxidative metabolism was measured using the mono-exponential fit of the myocardial [(11)C] acetate positron emission tomography time-activity curve (k-mono). Myocardial efficiency was derived using the work metabolic index (WMI = [heart rate x stroke volume index x systolic blood pressure]/k-mono) measured at baseline, during short-term CPAP, and after 6 +/- 3 weeks of CPAP. RESULTS: In group I, short-term CPAP tended to reduce SVI (p = 0.063) and reduced oxidative metabolism (p = 0.031). Work metabolic index did not change. However, longer term CPAP improved left ventricular ejection fraction (38.4 +/- 3.3% to 43.4 +/- 4.8%, p = 0.031), tended to reduce oxidative metabolism (0.047 +/- 0.012 to 0.040 +/- 0.008 min(-1), p = 0.078), and improved WMI (7.13 +/- 2.82 x 10(6) to 8.17 +/- 3.06 x 10(6) mm Hg.ml/m(2), p = 0.031). In group II (control), these parameters did not change. CONCLUSIONS: In this cohort of patients with HF and OSA, short-term CPAP decreased oxidative metabolism and tended to decrease SVI, but did not alter cardiac efficiency. Longer term CPAP improved cardiac efficiency, indicating an energy-sparing effect. These effects may contribute to the benefits of CPAP therapy.     

Effect of continuous positive airway pressure vs placebo continuous positive airway pressure on sleep quality in obstructive sleep apnea

STUDY OBJECTIVES: Continuous positive airway pressure (CPAP) therapy has become the treatment of choice for obstructive sleep apnea (OSA). However, the efficacy of CPAP therapy has not been evaluated against a suitable control. We investigated the effectiveness of CPAP therapy in improving sleep quality in patients with OSA. We hypothesized that CPAP improves sleep quality. PATIENTS: Forty-eight CPAP-naive OSA patients were evaluated. None were receiving antihypertensive medications, and none had major medical illnesses. DESIGN: Patients were randomized to receive either CPAP or placebo CPAP (CPAP at an ineffective pressure) for 7 days in a double-blind fashion. Forty-one patients completed the protocol. Sleep quality variables, arousals, sleep arterial oxygen saturation (SaO(2)), and respiratory disturbance index (RDI) were assessed at baseline, after 1 day of treatment, and after 7 days of treatment. Repeated measures analysis of variance was used to evaluate the effects of treatment, time, and the interaction of the two. RESULTS: As expected, CPAP lowered RDI and number of arousals, and increased SaO(2) over time (p = 0.001). Contrary to expectations, both CPAP and placebo CPAP had comparable effects on sleep quality as assessed by sleep architecture, sleep efficiency, total sleep time, and wake after sleep onset time. CONCLUSIONS: This study confirms the effectiveness of CPAP in lowering the number of arousals and the RDI, and in raising SaO(2). However, our data suggest that short-term CPAP is no different than placebo in improving sleep architecture. Further evaluation of the effectiveness of CPAP using a suitable placebo CPAP in prospective randomized studies is needed