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A Portable Device as Sleep-Screening Tool in the Identification of Obstructive Sleep Apnea in Chronic Heart Failure: Which Value Should We Consider as Cutoff?
ARTICLE IN PRESS Journal of Cardiac Failure Vol. ■■ No. ■■ 2015
Letter to the Editor A Portable Device as Sleep-Screening Tool in the Identification of Obstructive Sleep Apnea in Chronic Heart Failure: Which Value Should We Consider as Cutoff? • To the Editor: Early diagnosis of sleep-disordered breathing (SDB), such as obstructive sleep apnea (OSA) and central sleep apnea (CSA) is a key determinant to avoid long-term worsening in chronic heart failure (CHF).1,2 However, in today’s clinical practice, diagnosis of SDB requires polysomnography (PSG), which is rather complex and not widely applicable. During the past decade, use of home portable monitoring devices has been added as a novel option for diagnosis of SDB, but its role remains controversial.3 We read with great interest the article by Grietje de Vries et al entitled “Validity and Predictive Value of a Portable Two-Channel Sleep-Screening Tool in the Identification of Sleep Apnea in Patients With Heart Failure.”4 In that study, the authors analyzed recordings of home-based PSG versus a screening 2-channel device, Apnealink (AL), in selected patients with stable CHF. The authors clearly illustrated that AL was able to detect patients with and without sleep apnea with great accuracy. Therefore, it may qualify as a valid and very predictive screening tool for specialists in identifying those patients at risk of having sleep apnea and heart failure. In addition, there was solid agreement between AL and PSG. Limitations are related to the choice of an optimal cutoff value of the apnea-hypopnea index (AHI) at ≥15/h to establish an appropriate sensitivity and specificity. Their main recommendation was that the screening tool could be useful in excluding the presence of sleep apnea in CHF patients. Therefore, only high-risk patients for OSA should be addressed to perform PSG, thus reducing the need of an expensive and time-consuming investigation for all the other subjects. These results are very innovative; however, we would like to point out some comments on the study that should be considered.
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in patients with heart failure. In line with this, AL provides information about airflow via nasal pressure alone, but essential data related to sleep stage and respiratory effort were not collected. This information is important to make decisions on therapeutic strategies. From a practical point of view, the device is also less sensitive for OSA at the lowest levels of the AHI (5–14 events/ h). This means that in a subject with high pretest probability for OSA, a negative AL study should raise suspicion of a false negative. The authors focused their study on stable CHF, but they did not investigate patients at an early stage of SDB (AHI < 15/h). Current guidelines do not recommend home sleep monitoring for the aforementioned subjects. Furthermore, patients with SDB have been shown to suffer from both OSA and CSA events, which might change treatment.
For all the reasons listed above, we conclude that full PSG in a sleep laboratory should also be considered in those patients in which AL testing is equivocal or technically limited.7 Disclosures None. Pierluigi Carratù, MD, PhD1 Silvano Dragonieri, MD, PhD1 Onofrio Resta, MD1 Antonio M. Esquinas, MD, PhD, FCCP International Fellow AARC2 1 Institute of Respiratory Diseases, University of Medicine, Bari, Italy 2 Intensive Care and Noninvasive Ventilatory Unit Hospital Morales Meseguer, Murcia, Spain References 1. Kasai T. Sleep apnea and heart failure. J Cardiol 2012;60:78–85. Review. 2. Damy T, Margarit L, Noroc A, Bodez D, Guendouz S, Boyer L, et al. Prognostic impact of sleep-disordered breathing and its treatment with nocturnal ventilation for chronic heart failure. Eur J Heart Fail 2012;14:1009–19. 3. Lux L, Boehlecke B, Lohr KN. Effectiveness of portable monitoring devices for diagnosing obstructive sleep apnea: update of a systematic review [internetInternet]. Rockville, Maryland: Agency for Healthcare Research and Quality; 2004. Available at: http://www.ncbi.nlm.nih .gov/books/NBK299250/. 4. de Vries GE, van der Wal HH, Kerstjens HA, van Deursen VM, Stegenga B, van Veldhuisen DJ, et al. Validity and predictive value of a portable two-channel sleep-screening tool in the identification of sleep apnea in patients with heart failure. J Card Fail 2015;21:848–55.
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In the population selected by the authors, are there any correlations among OSA-CHF and other findings, such as coronary artery involvement, daytime sleepiness, and electrocardiography abnormalities?5 • When diagnosing SDB, AL does not discriminate obstructive from central events.6 Furthermore, AL does not record an electroencephelogram, which could be useful Authors have no conflict of interest to disclose.
1
ARTICLE IN PRESS 2 Journal of Cardiac Failure Vol. ■■ No. ■■ ■■ 2015 5. Javadi HR, Jalilolghadr S, Yazdi Z, Rezaie Majd Z. Correlation between obstructive sleep apnea syndrome and cardiac disease severity. Cardiovasc Psychiatry Neurol. 2014;2014:631380. 6. Oldenburg O. Cheyne-stokes respiration in chronic heart failure. Treatment with adaptive servoventilation therapy. Circ J 2012;76:2305–17. Review.
7. Aurora RN, Swartz R, Punjabi NM. Misclassification of OSA severity with automated scoring of home sleep recordings. Chest 2015;147:719–27. http://dx.doi.org/10.1016/j.cardfail.2015.10.014
Letter to the Editor A Portable Device as Sleep-Screening Tool in the Identification of Obstructive Sleep Apnea in Chronic Heart Failure: Which Value Should We Consider as Cutoff? • To the Editor: Early diagnosis of sleep-disordered breathing (SDB), such as obstructive sleep apnea (OSA) and central sleep apnea (CSA) is a key determinant to avoid long-term worsening in chronic heart failure (CHF).1,2 However, in today’s clinical practice, diagnosis of SDB requires polysomnography (PSG), which is rather complex and not widely applicable. During the past decade, use of home portable monitoring devices has been added as a novel option for diagnosis of SDB, but its role remains controversial.3 We read with great interest the article by Grietje de Vries et al entitled “Validity and Predictive Value of a Portable Two-Channel Sleep-Screening Tool in the Identification of Sleep Apnea in Patients With Heart Failure.”4 In that study, the authors analyzed recordings of home-based PSG versus a screening 2-channel device, Apnealink (AL), in selected patients with stable CHF. The authors clearly illustrated that AL was able to detect patients with and without sleep apnea with great accuracy. Therefore, it may qualify as a valid and very predictive screening tool for specialists in identifying those patients at risk of having sleep apnea and heart failure. In addition, there was solid agreement between AL and PSG. Limitations are related to the choice of an optimal cutoff value of the apnea-hypopnea index (AHI) at ≥15/h to establish an appropriate sensitivity and specificity. Their main recommendation was that the screening tool could be useful in excluding the presence of sleep apnea in CHF patients. Therefore, only high-risk patients for OSA should be addressed to perform PSG, thus reducing the need of an expensive and time-consuming investigation for all the other subjects. These results are very innovative; however, we would like to point out some comments on the study that should be considered.
•
in patients with heart failure. In line with this, AL provides information about airflow via nasal pressure alone, but essential data related to sleep stage and respiratory effort were not collected. This information is important to make decisions on therapeutic strategies. From a practical point of view, the device is also less sensitive for OSA at the lowest levels of the AHI (5–14 events/ h). This means that in a subject with high pretest probability for OSA, a negative AL study should raise suspicion of a false negative. The authors focused their study on stable CHF, but they did not investigate patients at an early stage of SDB (AHI < 15/h). Current guidelines do not recommend home sleep monitoring for the aforementioned subjects. Furthermore, patients with SDB have been shown to suffer from both OSA and CSA events, which might change treatment.
For all the reasons listed above, we conclude that full PSG in a sleep laboratory should also be considered in those patients in which AL testing is equivocal or technically limited.7 Disclosures None. Pierluigi Carratù, MD, PhD1 Silvano Dragonieri, MD, PhD1 Onofrio Resta, MD1 Antonio M. Esquinas, MD, PhD, FCCP International Fellow AARC2 1 Institute of Respiratory Diseases, University of Medicine, Bari, Italy 2 Intensive Care and Noninvasive Ventilatory Unit Hospital Morales Meseguer, Murcia, Spain References 1. Kasai T. Sleep apnea and heart failure. J Cardiol 2012;60:78–85. Review. 2. Damy T, Margarit L, Noroc A, Bodez D, Guendouz S, Boyer L, et al. Prognostic impact of sleep-disordered breathing and its treatment with nocturnal ventilation for chronic heart failure. Eur J Heart Fail 2012;14:1009–19. 3. Lux L, Boehlecke B, Lohr KN. Effectiveness of portable monitoring devices for diagnosing obstructive sleep apnea: update of a systematic review [internetInternet]. Rockville, Maryland: Agency for Healthcare Research and Quality; 2004. Available at: http://www.ncbi.nlm.nih .gov/books/NBK299250/. 4. de Vries GE, van der Wal HH, Kerstjens HA, van Deursen VM, Stegenga B, van Veldhuisen DJ, et al. Validity and predictive value of a portable two-channel sleep-screening tool in the identification of sleep apnea in patients with heart failure. J Card Fail 2015;21:848–55.
•
In the population selected by the authors, are there any correlations among OSA-CHF and other findings, such as coronary artery involvement, daytime sleepiness, and electrocardiography abnormalities?5 • When diagnosing SDB, AL does not discriminate obstructive from central events.6 Furthermore, AL does not record an electroencephelogram, which could be useful Authors have no conflict of interest to disclose.
1
ARTICLE IN PRESS 2 Journal of Cardiac Failure Vol. ■■ No. ■■ ■■ 2015 5. Javadi HR, Jalilolghadr S, Yazdi Z, Rezaie Majd Z. Correlation between obstructive sleep apnea syndrome and cardiac disease severity. Cardiovasc Psychiatry Neurol. 2014;2014:631380. 6. Oldenburg O. Cheyne-stokes respiration in chronic heart failure. Treatment with adaptive servoventilation therapy. Circ J 2012;76:2305–17. Review.
7. Aurora RN, Swartz R, Punjabi NM. Misclassification of OSA severity with automated scoring of home sleep recordings. Chest 2015;147:719–27. http://dx.doi.org/10.1016/j.cardfail.2015.10.014