title: Coronary dilatation after heart transplantation.
abstract: BACKGROUND
  The angiographic incidence of coronary dilatation (CD) in the nontransplant population is approximately 0.2% to 5%. The endothelial-dependent and -independent causes for CD are postulated. So far, the incidence and prognosis of CD after heart transplantation is unknown.
  
  
  METHODS
  We retrospectively analyzed the annual coronary angiographies of 688 heart transplant recipients regarding the incidence of CD (defined as ≥1.5-fold localized increased vessel diameter or diffuse dilatation involving more than 50% of the coronary artery). A subgroup analysis of coronary epicardial (quantitative angiography) and microvascular (doppler flow measurement) vasomotor function in response to acetylcholine (endothelial dependent) and adenosine (endothelial independent) as well as intravascular ultrasound was performed in 177 patients.
  
  
  RESULTS
  CD was detectable in 26 patients (3.8%) and was associated with stenosing coronary artery disease in 27% of the patients. Segments with CD tended to have less intimal hyperplasia compared with nondilated segments. A diffuse dilatation (type I-II) was present in 63% of the recipients. The right coronary artery was always involved. The patients with CD (5 of 177) showed a 31% reduced flow velocity in the dilated coronaries compared with the nondilated coronary arteries (P=0.03). Microvascular endothelial-independent function was impaired in CD by -29% (coronary flow reserve mean 1.9 vs. 2.7; P=0.04), whereas endothelial-dependent response was unchanged. Epicardial endothelial-dependent and -independent responses were not different between the groups. Incidence of CD was not associated with limited survival.
  
  
  CONCLUSIONS
  The incidence of CD in the nontransplant population is similar to that in the transplanted population. However, the latter shows a more diffuse extent. Heart transplantation patients with CD had microvascular endothelial-independent functional limitations and flow deceleration, whereas survival was not affected.
authors.affiliation: Medizinische Klinik und Poliklinik 1, Campus Großhadern, Ludwig- Maximilians Universität, Munich, Germany. tsnickel@web.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Nickel
authors.forename: Amir
authors.initials: A
authors.lastname: Bigdeli
authors.forename: Franz
authors.initials: F
authors.lastname: von Ziegler
authors.forename: Ute
authors.initials: U
authors.lastname: Wilbert-Lampen
authors.forename: Korbinian
authors.initials: K
authors.lastname: Lackermair
authors.forename: Sophia
authors.initials: S
authors.lastname: Horster
authors.forename: Eva
authors.initials: E
authors.lastname: Hoster
authors.forename: Peter
authors.initials: P
authors.lastname: Uberfuhr
authors.forename: Wolfgang
authors.initials: W
authors.lastname: von Scheidt
authors.forename: Michael
authors.initials: M
authors.lastname: Weis
authors.forename: Ingo
authors.initials: I
authors.lastname: Kaczmarek
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000241:Adenosine / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography; D017023:Coronary Angiography / Q000379:methods; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000503:physiopathology*; D004108:Dilatation, Pathologic / Q000209:etiology*; D042783:Endothelial Cells / Q000166:cytology; D005260:Female; D016027:Heart Transplantation / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology; D011379:Prognosis; D012189:Retrospective Studies
chemical_list: D000241:Adenosine; D000109:Acetylcholine