title: Predictors of reduced coronary flow reserve in heart transplant recipients without angiographically significant coronary artery disease.
abstract: BACKGROUND
  Determination of coronary flow reserve (CFR) is increasingly used to assess the functional significance of cardiac allograft vasculopathy. Although the relation between CFR and angiographically defined vasculopathy has been studied extensively, little is known about other factors determining CFR in heart transplant recipients without significant lesions by coronary angiography.
  
  
  METHODS
  Sixty consecutive patients were studied 0.5 to 148 months after heart transplantation with intracoronary Doppler and intravascular ultrasound. An endothelium-independent CFR< or =2.5 was defined as abnormal. Stepwise logistic regression analysis was used to identify factors (demographic data of donor and recipient, lipid profile, epicardial vessel morphology by intravascular ultrasound, left ventricular hypertrophy, acute rejection episodes, and hemodynamics) potentially associated with a reduced CFR.
  
  
  RESULTS
  Only the presence of left ventricular hypertrophy (48% vs. 14%, P=0.007 and P=0.023, bivariate and multivariate analysis, respectively) and higher donor ages (41+/-12 vs. 29+/-11 years, P=0.002 and P=0.013, bivariate and multivariate analysis, respectively) showed an independent association with an abnormal flow reserve. CFR in patients with left ventricular hypertrophy was reduced due to higher baseline flow velocities (27+/-11 vs. 20+/-6 cm/sec, P=0.004). Furthermore, resting flow velocity increased as a function of donor age (r=0.264, P=0.047), while hyperemic flow velocity was not different. Other patient characteristics and hemodynamics did not affect CFR.
  
  
  CONCLUSIONS
  The presence of left ventricular hypertrophy and higher donor ages independently contribute to a reduced CFR in patients after heart transplantation. This reduction in CFR is due to elevated baseline flow velocities rather than to a change in hyperemic flow velocities. These findings should be taken into account for the interpretation of reduced CFR values obtained by intracoronary Doppler in heart transplant recipients without angiographically overt coronary lesions.
authors.affiliation: Department of Internal Medicine, Klinikum Innenstadt, University of Munich, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Klauss
authors.forename: C H
authors.initials: CH
authors.lastname: Spes
authors.forename: J
authors.initials: J
authors.lastname: Rieber
authors.forename: U
authors.initials: U
authors.lastname: Siebert
authors.forename: F
authors.initials: F
authors.lastname: Werner
authors.forename: H U
authors.initials: HU
authors.lastname: Stempfle
authors.forename: P
authors.initials: P
authors.lastname: Uberfuhr
authors.forename: K
authors.initials: K
authors.lastname: Theisen
authors.forename: C E
authors.initials: CE
authors.lastname: Angermann
authors.forename: B
authors.initials: B
authors.lastname: Reichart
authors.forename: H
authors.initials: H
authors.lastname: Mudra
mesh_terms: D000328:Adult; D000367:Age Factors; D001794:Blood Pressure; D002784:Cholesterol / Q000097:blood; D003326:Coronary Circulation / Q000502:physiology*; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D016027:Heart Transplantation / Q000502:physiology*; D006439:Hemodynamics; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications; D011859:Radiography; D012044:Regression Analysis; D018570:Risk Assessment; D014019:Tissue Donors; D014280:Triglycerides / Q000097:blood; D014463:Ultrasonography
chemical_list: D014280:Triglycerides; D002784:Cholesterol