This study aimed to determine the prevalence of central sleep apnea (CSA) in children with heart failure secondary to dilated cardiomyopathy (DCM) and examine its clinical relevance. Of 37 children who underwent overnight polysomnography, 7 (19%) had a CSA as defined by an apnea-hypopnea index over 1. Those with CSA tended to be younger. While CSA occurs at lower rates in children with heart failure compared to adults, this first prospective study establishes CSA can affect some pediatric patients with DCM. Larger studies are needed to better understand CSA in this population.

1. Journal Club
Kaifi Siddiqui
Moderator :Dr Archana Kashyap

2. Title
Prospective Evaluation of Sleep Apnea as
Manifestation of Heart Failure in Children
• Susanna L. den Boer1, Koen F. M. Joosten2, Sandra van den Berg2Ad P. C. M. Backx3 Ronald B.
Tanke4 Gideon J. du Marchie Sarvaas5 Willem A. Helbing1 Lukas A. J. Rammeloo6 Arend D. J.
ten Harkel7 Gabrie¨lle G. van Iperen8 Michiel Dalinghaus
Pediatr Cardiol 51( 2017) 503-508.

3. Introduction
Central sleep apnea
• A heterogeneous group of sleep-related breathing disorder in
which respiratory effort is diminished or absent in an
intermittent or cyclical fashion during sleep.
• During polysomnography (PSG), a central apneic event is
defined as cessation of airflow for 10 sec or more without an
identifiable respiratory effort

4. Introduction
• In adults with heart failure, central sleep apnea (CSA) is highly
prevalent.
• Cheyne–Stokes respiration is a form of CSA , used as a
synonym for CSA.
• CSB-CSA has been reported in 25-40% of patients with heart
failure.
• The occurrence of CSA in adults with heart failure is
associated with the severity of heart failure and with higher
mortality rates.
• In children no study has been published that has investigated
whether CSA occurs in children with heart failure
• Dilated cardiomyopathy (DCM) is a severe cardiac disorder
resulting in heart failure.

5. Aims &Objective
• To determine the prevalence of Central sleep
apnea in children
• To determine the clinical relevance of CSA in
children with heart failure secondary to DCM.

6. Methods
• Study design:
Prospective Observational study
• Study Place:
Department of Pediatrics, Division of Pediatric
Cardiology,Sophia Children’s Hospital, Erasmus Medical Center,
The Netherlands
• Study duration:
October 2012 and October 2015

7. Methods
• Inclusion criteria
• Children (<18 year) with Dilated cardiomyopathy( left
ventricle end-diastolic dimension >95th percentile for body
surface area and a shortening fraction (SF) ≤25 %)
• All parents & patients > 12 years who gave written informed
consent.
• Exclusion criteria
• Patients with DCM secondary to neuromuscular diseases

8. Methods contd.
• An overnight polysomnography was done.
• A detailed clinical evaluation, echocardiography, NT-pro BNP
measurement.
• Clinical assessment using the New York University Pediatric
Heart Failure Index was done within 3 months of
polysomnography.
• Medication use and demographic data were recorded.
• Follow-up data were collected through January 2017.

9. Methods contd.
• Sleep Study
• Patients underwent overnight polysomnography at Home/ hospital.
• The Embletta*Portable Diagnostic System was used at home and
analyzed using Somnologica for Embletta Software 3.3 ENU
(Medcare Flage, Reykjavik, Iceland).
• In hospital, measurements were done using BrainRT Shell + (OSG
BVBA, Rumst, Belgium)
• Caregivers were instructed to apply all sensors and to start the
measurement at bedtime till next morning.
• Recordings of both devices were analyzed using the same methods
*Embletta is a multichannel test that continuously measures respiration by a pressure transducer
attached to a nasal cannula , breathing effort through respiratory elastic belts at abdominal and chest
level, and oxygen saturation (SaO2) and heart rate using an infant or pediatric oxygen sensor on a
fingertip.

10. Methods contd
• Scoring Respiratory Events
• One observer, blinded to the clinical details of patients, scored
the sleep studies.
• Scoring done as per American Academy of Sleep Medicine
(AASM) criteria.
• Apneawas defined as dropin peak signal excursions of ≥90 %.
• Central apnea scored if inspiratory effort was absent
throughout the entire duration of the event and one of the
following criteria :
• (1) the event lasted ≥20 s
• (2) the event lasted for at least 2 breaths and oxygen
desaturation of ≥3 %..

11. Methods contd.
• A central apnea following a sigh was scored only if it caused a
desaturation ≥3 %.
• Hypopnea - reduction of ≥30 % of the pre-events baseline
flow, lasted for at least 2 breaths and with desaturation of ≥3
%.
• The apnea–hypopnea index (AHI)- number of central apneas
and hypopneas per hour of sleep.
• An AHI of ≥1 abnormal.
• Periodic breathing was scored if ≥3 episodes of central apnea
lasted >3sec. separated by no more than 20s of normal
breathing

12. Statistical Analysis
• Continuous variables displayed as median (IQR);
low sample size
• Categorical variables - numbers and percentages.
• Difference between the median of two
independent groups –Mann Whitney test.
• Relationships between two non-normally
distributed continuous variables - Spearman’s
correlation.
• Statistical significance was defined as p<0.05.

13. Results
• 58 of 79 eligible agreed for polysomnography.
• Of 58, eight patients were not measured, as they died or had heart
transplantation shortly after inclusion
• In 13 patients the measurement failed, due to a lack of patient
cooperation , so 37 measurements were available.
• Median age was 11.1 years. The median time since diagnosis of
DCM was 3.6 years.
• Almost all patients (97 %) took ACE inhibitors, 81 % took b-blockers
and 70 % took diuretics as medical treatment for heart failure
• The median LVEDD z-score was +4.7 and SF 19.4 %.

14. Results contd.
• Sleep Study
• 33 patients (89 %) were measured at home with the
ambulatory device, four patients were measured in hospital.
• The median recording time was 513 min.
• Of 37 patients, seven (19 %) had AHI ≥1 (range 1.2–4.5).
• These children were significantly younger than children with
AHI <1 (median age 2.9 vs. 12.3 year, p = 0.01).
• Three patients were younger than 1 yr of age; all had an
abnormal AHI ≥1)

16. Discussion
• In 19 % of the children, we detected CSA, defined as AHI >1.
• No relation between the occurrence of CSA and the severity
of heart failure in children was found.
• The prevalence of CSA in children with heart failure was lower
than in adults with heart failure.
• An increased number of central sleep apneas and hypopneas
in seven children (19 %).
• CSA in children was defined as AHI ≥1/h, while in adults CSA
is defined as mild if AHI ≥5, moderate AHI 15–29 ,severe if
AHI ≥30.
• Compared to adults the severity of CSA in children was
relatively mild.

17. Limitations of the study
1. Substantial number of pts not measured due to technical &
practical problems.
2. Negative consent for polysomnography.
3. Eight children could not undergo a polysomnography
because of death or heart transplantation
4. In adults the prevalence increases with decreasing LV
function, CSA may be missed as severely ill subgroup not
studied.
5. Three patients with AHI >1 were < 1 yr. In infants,
CSA may be bec. of immature breathing, than of heart failure,
prevalence may be overestimated .

18. What this study proposes
• First prospective study to investigate the prevalence of
central sleep apnea in children with heart failure
• To have future research with increased no of eligible patients
by enrolling in hospital on all newly diagnosed patients
a. 80 % of the patients with DCM need hospital admission at
diagnosis
b. In-hospital measurements reduce the technical failure.
c. DCM symptoms may be worse during first admission, may
lead to a higher detection rate of CSA.

19. Related studies
• Congestive Heart Failure and Central Sleep Apnea
Scott A. Sands, PhD and Robert L. Owens, MD
• Mechanisms and Clinical Consequences of Untreated Central Sleep Apnea
in Heart Failure
• Maria Rosa Costanzo, MD,* Rami Khayat, MD,† Piotr Ponikowski, MD,‡§ Ralph Augostini,
MD,∥Christoph Stellbrink, MD,¶ Marcus Mianulli, BS,# and William T. Abraham, MD∥

20. Thank you