Embed Size (px)
Citation preview
Using Holter ECG and Heart Rate Variability to Detect
Sleep-Disordered Breathing
Phyllis K Stein, Ph.D. Heart Rate Variability Laboratory
Washington University School of Medicine
St. Louis, MO
Background
When patients with sleep-disordered breathing have an event, there is an autonomic arousal associated with a brief awakening, they then resume normal breathing, and fall back asleep.
This repeated awakening is associated with a repeated increase in heart rate which return to baseline when the patient falls back asleep.
Sleep Apnea Clarified
1. Sequence of unedited beat-to-beat R-R (or preferable edited N-N) intervals.
2. Convert R-R intervals to instantaneous HR (60,000/R-R interval in ms).
3. Plot tachogram of HR vs. time on 6 parallel 10-min plots (one hr/page).
Heart-Rate-Based Graphical Method for Detecting Sleep-Disordered Breathing
• x-axis = time in minutes (0-10 minutes)
• y-axis for each 10-min plot is H (0-100 bpm in 5 cm)
• “x-axis” is mean HR for that 10-min segment
Tachogram Axes
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
Tim e (M in.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
00:09:00
00:19:00
00:29:00
00:39:00
00:49:00
00:59:00
0-100 bpm
“x-axis”
Sleep Onset in a Patient Without OSAHS
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
Tim e (M in.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
00:09:00
00:19:00
00:29:00
00:39:00
00:49:00
00:59:00
To bed
Onset of OSAHS
00 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
HR1 Time (Min.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
01:59:00
02:09:00
02:19:00
02:29:00
02:39:00
02:49:00
Patient falls asleep
• Data based on R-R intervals using simple
QRS detection algorithm and not edited.• 35 tachograms blindly scored for OSA, no
OSA and indeterminate. # each category known.
• Graphical method, 1 pair wrong, severe sleep-disordered breathing but hypopneas not OSA.
Tachograms From the Computers In Cardiology Sleep Apnea Contest
CVHR Subject 2
Brady-tachy pattern not seen
CVHR Subject 5
Tachycardia during OSA
CVHR Subject 7
CVHR Subject 8
CVHR and Normal Sleep or Quiet Rest Subject 9
Probable change in position resulting in OSA
CVHR Subject 13
CVHR Subject 16 (Hypopneas)
CVHR Subject 19
CVHR Subject 20
CVHR Subject 21
CVHR Subject 23
Apnea Appears to be Positional in Subject 23
Change in position terminates apnea
CVHR Subject 25
CVHR Subject 26
CVHR Subject 27
CVHR Subject 28
CVHR Subject 30
Probable change in position-apnea more severe earlier
Severe Sleep Apnea Subject 31
Magnitude of RSA declines during some but not all events
Severe Sleep Apnea Subject 32
Probable change in position or sleep stage. RSA is reduced.
Tachogram Evaluation
• Identify epochs of CVHR (cyclic variation of heart rate)
• Quantify CVHR by by total number of minutes (to nearest 30s) with CVHR.
• If CVHR is predominant, no need to quantify.
CVHR Definition
• At least 3 consecutive cycles of rising and falling heart rate.
• A visible rise in heart rate (5 bpm).
• A return to baseline.
• Each cycle 10 s duration.
• At least 20s but less than 2 min between cycles.
• 20% of time in CVHR of any type
• High amplitude regular CVHR pathomnemonic for OSA
• Lower amplitude or irregular CVHR may be associated with apneas, hypopneas, periodic limb movements or arousals for no apparent reason.
CVHR Criteria for Significantly Abnormal Sleep
Results of Sleep Lab Validation of CVHR Tachogram Method
• 100% detection of significantly abnormal sleep.
• High amplitude regular CVHR always sleep apnea.
• Lower amplitude or irregular CVHR could be apneas or hypopneas or leg movements, a mixture or arousals for no apparent reason.
• Non-diagnostic for flat tachograms (extremely low HRV) or atrial fibrillation.
Heart Rate Patterns on Tachograms Can Detect More
Than Just Sleep Apnea
HR Patterns During Central Apneas
6000 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
H R 2 Tim e (M in.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
22:00:00
22:10:00
22:20:00
22:30:00
22:40:00
22:50:00
HR Patterns During Severe De-Saturation
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
H R 2 Tim e (M in .)
0 0 .5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
21:59:00
22:09:00
22:19:00
22:29:00
22:39:00
22:49:00
O2 Sat = 65%
Irregular Low Amplitude CVHR
Low Amplitude CVHR Possibly Associated with Mixed Events
HR Patterns Associated with Periodic Limb Movements
12000 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
HR 3 Tim e (M in.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
01:28:00
01:38:00
01:48:00
01:58:00
02:08:00
02:18:00
Cheyne-Stokes Breathing
Cheyne-Stokes Breathing
Blown Up Section of Prior Tachogram Showing RSA During Cheyne-Stokes
Respiration
Power Spectral Analysis of Heart Rate Variability
to Detect Sleep-Disordered Breathing
• HRV power spectral plot quantifies the underlying periodicities in heart rate.
• CVHR is a periodic change in heart rate which should be reflected in the HRV power spectrum
Normal-Appearing Nighttime Power Spectral Plot
HF Peak Due to RSA
Onset of OSAHS
00 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
HR1 Time (Min.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
01:59:00
02:09:00
02:19:00
02:29:00
02:39:00
02:49:00
Patient falls asleep
Power Spectral Plot for Previous TachogramShowing OSAHS Pattern
VLF Peak Associated with Sleep Apnea
HF Peak Due to RSA
0.8 Hz0
HR Patterns During Central Apneas
6000 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
H R 2 Tim e (M in.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
22:00:00
22:10:00
22:20:00
22:30:00
22:40:00
22:50:00
0.8 Hz0
Power Spectral Plot for Previous Tachogram
Showing HRV Pattern for Central Apneas
VLF Peak Associated with Central Apneas
Little or no HF power
HR Patterns During Severe De-Saturation
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
H R 2 Tim e (M in .)
0 0 .5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
21:59:00
22:09:00
22:19:00
22:29:00
22:39:00
22:49:00
O2 Sat =65%
Irregular Low Amplitude CVHR
Power Spectral Plot for Previous Tachogram
Diffuse HF Peak Reflecting IrregularRespiration or Heart Rate Pattern
VLF Peak Associated with OSAHS
0.8 Hz0
Cheyne-Stokes Breathing
2-Min Averaged HRV Pattern for Cheyne-Stokes Respiration
Hard to see CSR peak
Hourly HRV Power Spectral Plots for Cheyne-Stokes Breathing
HR Patterns Associated with PLMs
12000 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
HR3 Tim e (M in.)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10
01:28:00
01:38:00
01:48:00
01:58:00
02:08:00
02:18:00
Power Spectral Plot for Previous Tachogram
Showing Periodic Limb Movements
VLF Peak Due to PLMS (0.04 Hz)
HF Peak Due to RSA
0 0.8 Hz
Conclusions1. Sleep apnea and other sleep-disturbing
syndromes can easily be identified from heart rate tachograms generated from routine Holter recordings
2. Visual examination of HRV patterns generated from hourly power spectral plots often available on commercial Holter scanners may help identify patients with CVHR.
3. Method is not valid for patients with significant autonomic dysfunction resulting in flat tachograms or in patients with atrial fibrillation
