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Increased ventricular premature contraction frequency during rem sleep in patients with coronary artery disease and obstructive sleep apnea.

Watanabe MA, Bhalodia R, Lundequam EJ, Domitrovich PP, Steinmeyer BC, Stein PK, Freedland KE, Duntley SP, Carney RM - Indian Pacing Electrophysiol J (2008)

Bottom Line: VPC frequency was affected significantly by sleep stage (Wake, S2 and REM, F=5.8, p<.005) and by AHI (F=8.7, p<.005).Oxygen desaturation duration per apnea episode correlated positively with AHI (r(2)=.71, p<.0001), and was longer in REM than in non-REM (p<.0001).The heart rate turbulence parameter TS correlated negatively with oxygen desaturation duration in REM (r(2)=.06, p=.014).

View Article: PubMed Central - PubMed

Affiliation: Internal Medicine Department, St. Louis University, USA. watanabe@slu.edu

ABSTRACT

Background: Patients with obstructive sleep apnea are reported to have a peak of sudden cardiac death at night, in contrast to patients without apnea whose peak is in the morning. We hypothesized that ventricular premature contraction (VPC) frequency would correlate with measures of apnea and sympathetic activity.

Methods: Electrocardiograms from a sleep study of 125 patients with coronary artery disease were evaluated. Patients were categorized by apnea-hypopnea index (AHI) into Moderate (AHI <15) or Severe (AHI>15) apnea groups. Sleep stages studied were Wake, S1, S2, S34, and rapid eye movement (REM). Parameters of a potent autonomically-based risk predictor for sudden cardiac death called heart rate turbulence were calculated.

Results: There were 74 Moderate and 51 Severe obstructive sleep apnea patients. VPC frequency was affected significantly by sleep stage (Wake, S2 and REM, F=5.8, p<.005) and by AHI (F=8.7, p<.005). In Severe apnea patients, VPC frequency was higher in REM than in Wake (p=.011). In contrast, patients with Moderate apnea had fewer VPCs and exhibited no sleep stage dependence (p=.19). Oxygen desaturation duration per apnea episode correlated positively with AHI (r(2)=.71, p<.0001), and was longer in REM than in non-REM (p<.0001). The heart rate turbulence parameter TS correlated negatively with oxygen desaturation duration in REM (r(2)=.06, p=.014).

Conclusions: Higher VPC frequency coupled with higher sympathetic activity caused by longer apnea episodes in REM sleep may be one reason for increased nocturnal death in apneic patients.

No MeSH data available.


Related in: MedlinePlus

Correlation between oxygen desaturation duration/ apnea event and AHI. Duration of oxygen desaturation >2% (sec) from baseline per apnea event was more closely correlated with AHI and shorter in duration in non-REM sleep compared to REM sleep. Each patient is represented by one AHI value and two oxygen desaturation duration values, one for REM (filled circle) and one for non-REM (empty circle) sleep.
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Figure 3: Correlation between oxygen desaturation duration/ apnea event and AHI. Duration of oxygen desaturation >2% (sec) from baseline per apnea event was more closely correlated with AHI and shorter in duration in non-REM sleep compared to REM sleep. Each patient is represented by one AHI value and two oxygen desaturation duration values, one for REM (filled circle) and one for non-REM (empty circle) sleep.

Mentions: Although TS and TO values did not correlate with AHI (apnea frequency), they did correlate with measures of apnea duration. Oxygen desaturation duration (DesatDurn) per apnea event was plotted against AHI value for REM and non-REM (S1, S2, and S34) sleep (Figure 3). We observed that: (1) DesatDurn correlated significantly and positively with AHI (r2=.71, p <.0001 for REM; r2=.87, p<.0001 for non-REM). (2) On average, DesatDurn was longer in REM sleep (p<.0001). (3) DesatDurn was less well correlated with AHI in REM sleep. With respect to heart rate turbulence, TS values became more abnormal (decreased) (p=.014) as REM DesatDurn increased (Figure 4). There was no correlation between non-REM DesatDurn and either TS or TO (both p>.3). VPC frequency correlated with REM DesatDurn (p < .0001). Both TS and TO became more abnormal as relative DesatDurn increased (TS p<.01; TO p=.002), where relative DesatDurn was defined as REM DesatDurn - non-REM DesatDurn. Relative DesatDurn quantified the magnitude of DesatDurn in REM relative to that expected for a given AHI. Non-REM DesatDurn was convenient as a surrogate measure of AHI in having the same units as REM DesatDurn.


Increased ventricular premature contraction frequency during rem sleep in patients with coronary artery disease and obstructive sleep apnea.

Watanabe MA, Bhalodia R, Lundequam EJ, Domitrovich PP, Steinmeyer BC, Stein PK, Freedland KE, Duntley SP, Carney RM - Indian Pacing Electrophysiol J (2008)

Correlation between oxygen desaturation duration/ apnea event and AHI. Duration of oxygen desaturation >2% (sec) from baseline per apnea event was more closely correlated with AHI and shorter in duration in non-REM sleep compared to REM sleep. Each patient is represented by one AHI value and two oxygen desaturation duration values, one for REM (filled circle) and one for non-REM (empty circle) sleep.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2572026&req=5

Figure 3: Correlation between oxygen desaturation duration/ apnea event and AHI. Duration of oxygen desaturation >2% (sec) from baseline per apnea event was more closely correlated with AHI and shorter in duration in non-REM sleep compared to REM sleep. Each patient is represented by one AHI value and two oxygen desaturation duration values, one for REM (filled circle) and one for non-REM (empty circle) sleep.
Mentions: Although TS and TO values did not correlate with AHI (apnea frequency), they did correlate with measures of apnea duration. Oxygen desaturation duration (DesatDurn) per apnea event was plotted against AHI value for REM and non-REM (S1, S2, and S34) sleep (Figure 3). We observed that: (1) DesatDurn correlated significantly and positively with AHI (r2=.71, p <.0001 for REM; r2=.87, p<.0001 for non-REM). (2) On average, DesatDurn was longer in REM sleep (p<.0001). (3) DesatDurn was less well correlated with AHI in REM sleep. With respect to heart rate turbulence, TS values became more abnormal (decreased) (p=.014) as REM DesatDurn increased (Figure 4). There was no correlation between non-REM DesatDurn and either TS or TO (both p>.3). VPC frequency correlated with REM DesatDurn (p < .0001). Both TS and TO became more abnormal as relative DesatDurn increased (TS p<.01; TO p=.002), where relative DesatDurn was defined as REM DesatDurn - non-REM DesatDurn. Relative DesatDurn quantified the magnitude of DesatDurn in REM relative to that expected for a given AHI. Non-REM DesatDurn was convenient as a surrogate measure of AHI in having the same units as REM DesatDurn.

Bottom Line: VPC frequency was affected significantly by sleep stage (Wake, S2 and REM, F=5.8, p<.005) and by AHI (F=8.7, p<.005).Oxygen desaturation duration per apnea episode correlated positively with AHI (r(2)=.71, p<.0001), and was longer in REM than in non-REM (p<.0001).The heart rate turbulence parameter TS correlated negatively with oxygen desaturation duration in REM (r(2)=.06, p=.014).

View Article: PubMed Central - PubMed

Affiliation: Internal Medicine Department, St. Louis University, USA. watanabe@slu.edu

ABSTRACT

Background: Patients with obstructive sleep apnea are reported to have a peak of sudden cardiac death at night, in contrast to patients without apnea whose peak is in the morning. We hypothesized that ventricular premature contraction (VPC) frequency would correlate with measures of apnea and sympathetic activity.

Methods: Electrocardiograms from a sleep study of 125 patients with coronary artery disease were evaluated. Patients were categorized by apnea-hypopnea index (AHI) into Moderate (AHI <15) or Severe (AHI>15) apnea groups. Sleep stages studied were Wake, S1, S2, S34, and rapid eye movement (REM). Parameters of a potent autonomically-based risk predictor for sudden cardiac death called heart rate turbulence were calculated.

Results: There were 74 Moderate and 51 Severe obstructive sleep apnea patients. VPC frequency was affected significantly by sleep stage (Wake, S2 and REM, F=5.8, p<.005) and by AHI (F=8.7, p<.005). In Severe apnea patients, VPC frequency was higher in REM than in Wake (p=.011). In contrast, patients with Moderate apnea had fewer VPCs and exhibited no sleep stage dependence (p=.19). Oxygen desaturation duration per apnea episode correlated positively with AHI (r(2)=.71, p<.0001), and was longer in REM than in non-REM (p<.0001). The heart rate turbulence parameter TS correlated negatively with oxygen desaturation duration in REM (r(2)=.06, p=.014).

Conclusions: Higher VPC frequency coupled with higher sympathetic activity caused by longer apnea episodes in REM sleep may be one reason for increased nocturnal death in apneic patients.

No MeSH data available.


Related in: MedlinePlus