Screening of Sleep Apnea by Holter Electrocardiography: Validation of Heart Rate Variability Analysis Algorithm
Condition: Sleep Apnea Syndromes
MeSH terms: Apnea; Sleep Apnea Syndromes; Syndrome
Study type: Interventional

Summary: 
      Obstructive sleep apnea syndrome (OSAS) is a growing health concern affecting up to 60 % of
      population with cardiovascular disease. Despite the high cardiovascular morbidity and
      mortality associated with this syndrome, the substantial inconvenience and cost of
      polysomnography recordings may delay routine evaluation. Polysomnography (PSG) is the gold
      standard for diagnosis. However, this is a costly and time-consuming examination.
      Sympathoadrenergic balance obtained from the routine Holter monitoring suggesting the
      presence of OSAS, can enable patients to be guided and their PSGs to be primarily
      held.Abnormalities in nocturnal cyclical heart rate (HR) variations have previously been
      described in sleep-related breathing disorders. Compared with PSG, holter electrocardiogram
      has the advantages of pervasion, lower cost, no need for overnight hospitalization, greater
      similarity to normal conditions, and good compliance. The observation of changes in heart
      rate associated with apneic events has a potential to be used as an alternative technique for
      identification of subjects with OSAS. In regard to the feasibility of screening OSAS by HRV
      analysis by holter electrocardiogram monitoring, it has already been reported that a 24-h
      electrocardiographic monitoring might be useful to diagnose OSAS. It became a more feasible
      technique to use following the development of a convenient recorder for OSAS screening by
      analyzing changes in heart rate.
    

Detailed description: 
      To find out whether a new algorithm of HRV analysis from holter ECG monitoring can be used as
      a screening test for the diagnosis of patients with moderate-to-severe risk of obstructive
      sleep apnea syndrome (OSAS) with an acceptable accuracy.For this, overnight sleep pattern
      will be investigated in at least 107 individuals by polysomnography and 24-h ambulatory
      electrocardiography. Heart rate variability sleep apnea risk score (HRV-SARS) will be
      calculated using HRV analyses.

      The patients were recruited from individuals referred to our university hospital's sleep
      center for a polysomnography recording because of clinically suspected OSAS (with at least
      one of the following obstructive sleep apnea symptoms: witnessed apnea, snoring and/or
      daytime sleepiness) from May to July 2022. Prospectively 107 patients enrolled in the study
      according to inclusion and exclusion criteria. Exclusion criteria were permanent or
      paroxysmal atrial fibrillation, permanent pacemaker, history of other sleep disorders, severe
      cardiopulmonary disease, severe diabetes mellitus, autonomic dysfunction or major physical or
      mental ailments. All patients underwent both a full polysomnography recording and ECG Holter
      monitoring.

      This new algorithm of HRV analysis from holter ECG monitoring may represent an accurate and
      inexpensive screening tool in clinically suspected OSAS patients and may help focus resources
      on those at the highest risk.
    

Intervention name(s): Holter ECG Monitoring
Intervention type(s): Device
Intervention description(s): Holter electrocardiogram monitoring will be carried out for 24 h simultaneously with the PSG monitoring using a 2- lead ambulatory electrocardiograph (Fysiologic; kind courtesy: MedTech Company, Amsterdam, Holland). We will calculate the time-domain, frequency-domain and non-linear indices by HRV. Several parameters describing the differences between RR intervals will be calculated: the square root of the mean of the sum of the squares of differences between adjacent normal RR intervals (r-MSSD), SD of NN intervals (SDNN), SD of the averages of NN intervals in all 5-minute segments of the recording (SDANN), and mean of the SD of all NN intervals for all consecutive 5-minute segments of the recording (SDNN index). All variables will be calculated for the 24-hour, daytime (2:00 to 9:00 PM), and nighttime (midnight to 7 AM) periods, and the differences between daytime and nighttime values (D[D/N]) will be computed.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Heart rate variability, Holter ECG monitoring