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Shahrokh Javaheri - One of the best experts on this subject based on the ideXlab platform.

  • update on apneas of heart failure with reduced ejection fraction emphasis on the physiology of treatment part 2 central sleep apnea
    Chest, 2020
    Co-Authors: Shahrokh Javaheri, Lee K Brown, Rami Khayat
    Abstract:

    Central sleep apnea/Hunter-Cheyne-Stokes Breathing (CSA/HCSB) is prevalent in patients with heart failure with reduced ejection fraction (HFrEF). The acute pathobiologic consequences of CSA/HSCB eventually lead to sustained sympathetic overactivity, repeated hospitalization, and premature mortality. A few randomized controlled trials (RCTs) have shown statistically significant and clinically important reduction in sympathetic activity when CSA/HCSB is attenuated by oxygen or PAP therapy. Yet, the two largest PAP RCTs in patients with HFrEF, one with CPAP and the other with adaptive servoventilation (ASV), were negative with respect to their primary outcomes, and both were associated with excess mortality. However, both trials suffered from significant deficiencies, casting doubt on their results. A second RCT evaluating an ASV device with an advanced algorithm is ongoing. A new modality of therapy, unilateral phrenic nerve stimulation, has undergone an RCT that demonstrated an improvement in CSA that was associated with a reduction in arousals, improvement in sleepiness, and improvement in quality of life. However, a long-term mortality trial has not been performed with this modality. Most recently, the National Institutes of Health has funded a long-term, phase 3 RCT of low-flow oxygen vs sham for the treatment of CSA/HCSB in HFrEF. The composite primary outcome includes all-cause mortality and hospitalization for worsening HF. In this article, we focus on various therapeutic options for the treatment of CSA/HCSB and, when appropriate, emphasize the importance of identifying CSA/HCSB phenotypes to tailor treatment.

  • positive airway pressure therapy for hyperventilatory central sleep apnea idiopathic heart failure cerebrovascular disease and high altitude
    Sleep Medicine Clinics, 2017
    Co-Authors: Shahrokh Javaheri, Lee K Brown
    Abstract:

    Central sleep apnea (CSA) and Hunter-Cheyne-Stokes Breathing (HCSB) are caused by failure of the pontomedullary pacemaker generating Breathing rhythm. CSA/HCSB may complicate several disorders causing recurrent arousals and desaturations. Common causes of CSA in adults are congestive heart failure, stroke, and chronic use of opioids; opioids have hypoventilatory effects. Diagnosis and treatment of hyperventilatory CSA may improve quality of life, and, when associated with heart failure or cerebrovascular disease, reduce morbidity and perhaps mortality.

  • acetazolamide attenuates hunter Cheyne Stokes Breathing but augments the hypercapnic ventilatory response in patients with heart failure
    Annals of the American Thoracic Society, 2014
    Co-Authors: Shahrokh Javaheri, Scott A Sands, Bradley A Edwards
    Abstract:

    Rationale: Acetazolamide has been used to attenuate Hunter-Cheyne-Stokes Breathing with central sleep apnea (CSA) associated with heart failure. However, the mechanisms underlying this improvement remain to be fully elucidated.Objectives: We hypothesized that acetazolamide stabilizes CSA by attenuating the ventilatory sensitivity to CO2, which is increased in patients with heart failure and is thought to be the major mechanism mediating CSA.Methods: Six consecutive male patients with stable systolic heart failure and CSA (apnea-hypopnea index [AHI] ≥ 15 episodes/h) were randomized to a double-blind crossover protocol with acetazolamide or placebo received 1 hour before bedtime for six nights with 2 weeks of wash-out. Under both conditions, we measured the hypercapnic ventilatory response (HCVR), arterial blood Pco2, steady-state metabolic CO2 production, overnight attended polysomnography, and also assessed cardiac and pulmonary function.Measurements and Main Results: Compared with placebo, acetazolamide ...

  • central sleep apnea right ventricular dysfunction and low diastolic blood pressure are predictors of mortality in systolic heart failure
    Journal of the American College of Cardiology, 2007
    Co-Authors: Shahrokh Javaheri, Rakesh Shukla, Haoyue Zeigler, Laura F Wexler
    Abstract:

    Objectives The purpose of this study was to determine whether central sleep apnea (CSA) contributes to mortality in patients with heart failure (HF). Background Cheyne-Stokes Breathing with CSA commonly occurs in patients with systolic HF. Consequences of CSA, including altered blood gases and neurohormonal activation, could result in further left ventricular dysfunction. Therefore, we hypothesized that CSA might contribute to mortality of patients with HF. Methods We followed 88 patients with systolic HF (left ventricular ejection fraction ≤45%) with (n = 56) or without (n = 32) CSA. The median follow-up was 51 months. Results The mean (±SD) of apnea-hypopnea index was significantly higher in patients with CSA (34 ± 25/h) than those without CSA (2 ± 1/h). Most of these events were central apneas. In Cox multiple regression analysis, 3 of 24 confounding variables independently correlated with survival. The median survival of patients with CSA was 45 months compared with 90 months of those without CSA (hazard ratio = 2.14, p = 0.02). The other 2 variables that correlated with poor survival were severity of right ventricular systolic dysfunction and low diastolic blood pressure. Conclusions In patients with systolic HF, CSA, severe right ventricular systolic dysfunction, and low diastolic blood pressure might have an adverse effect on survival.

Vincent Jobin - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of upper airway patency during Cheyne Stokes Breathing in heart failure patients
    European Respiratory Journal, 2012
    Co-Authors: Douglas T. Bradley, Vincent Jobin, Jordi Rigau, Josee Beauregard, Ramon Farre, Josep Monserrat, John R. Kimoff
    Abstract:

    Little is known about the changes in upper airway calibre in Cheyne-Stokes respiration (CSR) during sleep in patients with congestive heart failure. This study aimed to test the hypothesis that upper airway closure occurs during central CSR events, by assessing upper airway calibre during sleep using the forced oscillation technique (FOT). Nine males with compensated heart failure (left ventricular ejection fraction mean ± sem 27.9 ± 5.1%) and predominant central CSR (apnoea/hypopnoea index 43.9 ± 4.2 events · h(-1)) were studied during overnight polysomnography, which included pneumotachography, inductance plethysmography or oesophageal pressure and FOT-derived impedance signal (|Z|). Baseline |Z| values during stable Breathing in stage 2 sleep were 11.0 ± 1.3 cmH(2)O · s · L(-1). Mean |Z| increased to 31.9 ± 6.7 cmH(2)O · s · L(-1) during obstructive apnoeas (7% of events, n = 46). Increases in |Z| consistent with upper airway narrowing (more than two-fold baseline) were common during central apnoeas (50 ± 12% of events) occurring in the middle or end of apnoeas and occurred during some central hypopnoeas (16 ± 10% of events), typically in the expiratory phase. These findings indicate that in heart failure patients, reductions in upper airway calibre are common during CSR apnoeas, and may also occur during central hypopnoeas.

Rami Khayat - One of the best experts on this subject based on the ideXlab platform.

  • update on apneas of heart failure with reduced ejection fraction emphasis on the physiology of treatment part 2 central sleep apnea
    Chest, 2020
    Co-Authors: Shahrokh Javaheri, Lee K Brown, Rami Khayat
    Abstract:

    Central sleep apnea/Hunter-Cheyne-Stokes Breathing (CSA/HCSB) is prevalent in patients with heart failure with reduced ejection fraction (HFrEF). The acute pathobiologic consequences of CSA/HSCB eventually lead to sustained sympathetic overactivity, repeated hospitalization, and premature mortality. A few randomized controlled trials (RCTs) have shown statistically significant and clinically important reduction in sympathetic activity when CSA/HCSB is attenuated by oxygen or PAP therapy. Yet, the two largest PAP RCTs in patients with HFrEF, one with CPAP and the other with adaptive servoventilation (ASV), were negative with respect to their primary outcomes, and both were associated with excess mortality. However, both trials suffered from significant deficiencies, casting doubt on their results. A second RCT evaluating an ASV device with an advanced algorithm is ongoing. A new modality of therapy, unilateral phrenic nerve stimulation, has undergone an RCT that demonstrated an improvement in CSA that was associated with a reduction in arousals, improvement in sleepiness, and improvement in quality of life. However, a long-term mortality trial has not been performed with this modality. Most recently, the National Institutes of Health has funded a long-term, phase 3 RCT of low-flow oxygen vs sham for the treatment of CSA/HCSB in HFrEF. The composite primary outcome includes all-cause mortality and hospitalization for worsening HF. In this article, we focus on various therapeutic options for the treatment of CSA/HCSB and, when appropriate, emphasize the importance of identifying CSA/HCSB phenotypes to tailor treatment.

Steven Mcgee - One of the best experts on this subject based on the ideXlab platform.

  • Cheyne Stokes Breathing and reduced ejection fraction
    The American Journal of Medicine, 2013
    Co-Authors: Steven Mcgee
    Abstract:

    Abstract Background The accuracy of Cheyne-Stokes Breathing as a sign of left ventricular dysfunction and its overall prognostic significance are unknown. Methods Between 2001 and 2006, the author examined 386 inpatients at a Department of Veterans Affairs Medical Center and compared the finding of Cheyne-Stokes Breathing and its cycle length with the patients' echocardiographic ejection fraction (EF) and 5-year survival. Results A total of 45 of 386 patients (11.7%) had Cheyne-Stokes Breathing. Two variables were independently associated with Cheyne-Stokes Breathing: reduced EF ( P 001) and age>80 years ( P=. 006). The presence of Cheyne-Stokes Breathing increased the probability of a markedly reduced EF (ie, EF r =0.23, P=. 14). The 5-year survival of patients with Cheyne-Stokes Breathing (37.2%) was similar to that of patients without the finding (42.9%, P=. 18, log-rank test). Conclusions In hospitalized patients, Cheyne-Stokes Breathing increases the probability of left ventricular dysfunction. It is present in 1 of 3 patients with markedly reduced EF. When detected during physical examination, Cheyne-Stokes Breathing does not indicate worse prognosis.

John R. Kimoff - One of the best experts on this subject based on the ideXlab platform.

  • EVALUATION OF UPPER AIRWAY PATENCY DURING Cheyne- Stokes Breathing IN HEART FAILURE PATIENTS.
    2016
    Co-Authors: Monserrat M. D, Douglas T. Bradley, John R. Kimoff
    Abstract:

    Little is known about changes in upper airway caliber in Cheyne-Stokes Respiration (CSR) during sleep in patients with congestive heart failure. This study aimed to test the hypothesis that upper airway closure occurs during central CSR events, by assessing upper airway caliber during sleep using the forced oscillation technique (FOT). Nine males with compensated heart failure (mean left ventricular ejection fraction 27.9 5.1 (SEM) %) and predominant central CSR (apnea-hypopnea index = 43.9 4.2 events/h) were studied during overnight polysomnography, which included pneumotachography, inductance plethysmography or esophageal pressure, and a FOT-derived impedance signal (Z). Baseline Z values during stable Breathing in stage 2 sleep were 11.0 ± 1.3 cm H2O*s/L. Mean Z increased to 31.9 ± 6.7 cm H2O*s/L during obstructive apneas (7 % of events, n=46). Increases in Z consistent with upper airway narrowing (> 2-fold baseline) were common during central apneas (50 ± 12 % of events) occurring in the middle or end of apneas and occurred during some (16 ± 10 % of events) central hypopneas, typically in the expiratory phase

  • evaluation of upper airway patency during Cheyne Stokes Breathing in heart failure patients
    European Respiratory Journal, 2012
    Co-Authors: Douglas T. Bradley, Vincent Jobin, Jordi Rigau, Josee Beauregard, Ramon Farre, Josep Monserrat, John R. Kimoff
    Abstract:

    Little is known about the changes in upper airway calibre in Cheyne-Stokes respiration (CSR) during sleep in patients with congestive heart failure. This study aimed to test the hypothesis that upper airway closure occurs during central CSR events, by assessing upper airway calibre during sleep using the forced oscillation technique (FOT). Nine males with compensated heart failure (left ventricular ejection fraction mean ± sem 27.9 ± 5.1%) and predominant central CSR (apnoea/hypopnoea index 43.9 ± 4.2 events · h(-1)) were studied during overnight polysomnography, which included pneumotachography, inductance plethysmography or oesophageal pressure and FOT-derived impedance signal (|Z|). Baseline |Z| values during stable Breathing in stage 2 sleep were 11.0 ± 1.3 cmH(2)O · s · L(-1). Mean |Z| increased to 31.9 ± 6.7 cmH(2)O · s · L(-1) during obstructive apnoeas (7% of events, n = 46). Increases in |Z| consistent with upper airway narrowing (more than two-fold baseline) were common during central apnoeas (50 ± 12% of events) occurring in the middle or end of apnoeas and occurred during some central hypopnoeas (16 ± 10% of events), typically in the expiratory phase. These findings indicate that in heart failure patients, reductions in upper airway calibre are common during CSR apnoeas, and may also occur during central hypopnoeas.