Occult @entity25 XXXX in stable @entity712 .

@entity1 @entity712 @entity387 @entity1353 @entity7672 @entity204 @entity943 @entity25 @entity1002 @entity386
OBJECTIVE: To determine the prevalence and effect of @entity25 @entity1353 in ambulatory @entity1 with stable, optimally treated @entity712 . DESIGN: A prospective, longitudinal study. SETTING: Referral sleep laboratory of a Department of Veterans Affairs medical center. @entity1 : 42 of the 48 eligible @entity1 with stable @entity712 and @entity1002 (left ventricular ejection fraction < or = 45%). MEASUREMENTS: After an adaptation night, polysomnography and Holter monitoring were done in the sleep laboratory. Arterial blood gases and pH were measured, and cardiac radionuclide ventriculography and pulmonary, renal, and thyroid function tests were done. RESULTS: @entity1 were divided into two groups. Group I (n = 23) had an hourly rate of @entity386 and @entity387 ( @entity386 - @entity387 index) of 20 episodes per hour or less; group II (n = 19 [45%; CI, 30% to 60%]) had an index of more than 20 episodes per hour. In group II, the index varied from 26.5 to 82.2 episodes per hour (mean +/- SD, 44 +/- 13 episodes per hour; CI, 38 to 51 episodes per hour). Group II had significantly more arousals (24 +/- 12 compared with 3 +/- 3 in group I) that were directly attributable to episodes of @entity386 and @entity387 , longer periods of time with an arterial @entity7672 saturation of less than 90% (23% +/- 24% of total sleep time compared with 2% +/- 4%), lower arterial oxyhemoglobin saturation during sleep (74% +/- 13% compared with 87% +/- 4%), lower left ventricular ejection fraction (22% +/- 9% compared with 30% +/- 10%), and a significantly increased number of episodes of nocturnal @entity943 . Multiple regression analyses showed that @entity1002 was an independent risk factor for @entity387 in @entity1 with @entity712 . CONCLUSIONS: The prevalence of severe occult @entity25 @entity1353 is high in ambulatory @entity1 with stable, optimally treated chronic @entity712 . The @entity1353 episodes are associated with severe nocturnal arterial blood oxyhemoglobin desaturation and excessive arousals. Severe untreated @entity25 @entity1353 may adversely affect left ventricular function, resulting in a vicious cycle that could contribute to @entity204 in @entity1 with @entity712 . Prospective, longitudinal studies on survival are needed.
