title: Cardiac workload in patients with sleep-disordered breathing early after acute myocardial infarction.
abstract: BACKGROUND
  Sleep-disordered breathing (SDB) may promote an increase in cardiac workload early after acute myocardial infarction (AMI). We tested the hypothesis that in the early phase after AMI, SDB is associated with increased 24-h arterial BP, heart rate (HR), and, thus, cardiac workload.
  
  
  METHODS
  In this prospective study, 55 consecutive patients with AMI and subsequent percutaneous coronary intervention (78% men; mean age, 54 ± 10 y; mean BMI, 28.3 ± 3.6 kg/m²; mean left ventricular ejection fraction [LVEF], 47% ± 8%) underwent polysomnography and 24-h ambulatory BP and heart rate monitoring within 5 days after MI. Cardiac workload was calculated as systolic BP multiplied by HR. The presence of SDB was defined as ≥ 10 apneas and hypopneas per hour of sleep.
  
  
  RESULTS
  Fifty-five percent of the patients had SDB, of which 40% was predominantly central in nature. Patients with SDB had higher 24-h HR and systolic and diastolic BP compared with those without SDB (115 vs 108 mm Hg, P = .029; 71 vs 67 mm Hg, P = .034; 69 vs 64 beats/min, P = .050, respectively). Use of antihypertensive medication and β-receptor blockers was similar in both groups. In a multivariate linear regression analysis, SDB was significantly associated with an increased 24-h cardiac workload (β-coefficient, 0.364; 95% CI, 0.071-0.657; P = .016), independently of age, sex, BMI, LVEF, and antihypertensive medication.
  
  
  CONCLUSIONS
  Patients with AMI and SDB have significantly increased 24-h BP, HR, and cardiac workload. Treatment of SDB may be a valuable nonpharmacologic approach to lower cardiac workload in these patients.
authors.affiliation: Department of Pneumology, Donaustauf Hospital, Donaustauf, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Hetzenecker
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Buchner
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Greimel
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Satzl
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Luchner
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Kurt
authors.initials: K
authors.lastname: Debl
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Husser
authors.affiliation: Department of Radiology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Okka W
authors.initials: OW
authors.lastname: Hamer
authors.affiliation: Department of Radiology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fellner
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Günter A J
authors.initials: GAJ
authors.lastname: Riegger
authors.affiliation: Department of Pneumology, Donaustauf Hospital, Donaustauf, Germany; Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Pfeifer
authors.affiliation: Department of Internal Medicine II, Cardiology and Pneumology, University Hospital Regensburg, Regensburg, Germany. Electronic address: michael.arzt@klinik.uni-regensburg.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Arzt
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology*; D015897:Comorbidity; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology* / Q000503:physiopathology* / Q000628:therapy; D062645:Percutaneous Coronary Intervention; D011446:Prospective Studies; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000453:epidemiology* / Q000503:physiopathology*