title: Coronary endothelial dysfunction after heart transplantation predicts allograft vasculopathy and cardiac death.
abstract: BACKGROUND
  Coronary endothelial dysfunction may be an early marker for cardiac allograft vasculopathy (CAV) in orthotopic heart transplant recipients. Using serial studies with intravascular ultrasound and Doppler flow-wire measurements, we have previously demonstrated that annual decrements in coronary endothelial function are associated with progressive intimal thickening. The present study tested whether endothelial dysfunction predicts subsequent clinical events, including cardiac death and CAV development.
  
  
  RESULTS
  Seventy-three patients were studied yearly beginning at transplantation until a prespecified end point was reached. End points were angiographic evidence of CAV (>50% stenosis) or cardiac death (graft failure or sudden death). At each study, coronary endothelial function was measured with intracoronary infusions of adenosine (32-microgram bolus), acetylcholine (54 microgram over 2 minutes), and nitroglycerin (200 microgram) into the left anterior descending coronary artery; intravascular ultrasound images and Doppler velocities were recorded simultaneously. Of the 73 patients studied, 14 reached an end point during the study (6 CAV and 8 deaths, including 4 with known CAV, 1 graft failure, and 3 sudden). On the last study performed, the group with an end point had decreased epicardial (constriction of 11.1+/-2.9% versus dilation of 1.7+/-2.2%, P=0.01) and microvascular (flow increase of 75+/-20% versus 149+/-16%, P=0.03) endothelium-dependent responses to acetylcholine compared with the patients who did not reach an end point. Responses to adenosine and nitroglycerin did not differ significantly.
  
  
  CONCLUSIONS
  Endothelial dysfunction, as detected by abnormal responses to acetylcholine, preceded the development of clinical end points. These data implicate endothelial dysfunction in the development of clinically significant vasculopathy and suggest that serial studies of endothelial function have clinical utility.
authors.affiliation: Section of Cardiology, Rush-Presbyterian-St Luke's Medical Center, Chicago, Illinois, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Hollenberg
authors.forename: L W
authors.initials: LW
authors.lastname: Klein
authors.forename: J E
authors.initials: JE
authors.lastname: Parrillo
authors.forename: M
authors.initials: M
authors.lastname: Scherer
authors.forename: D
authors.initials: D
authors.lastname: Burns
authors.forename: P
authors.initials: P
authors.lastname: Tamburro
authors.forename: M
authors.initials: M
authors.lastname: Oberoi
authors.forename: M R
authors.initials: MR
authors.lastname: Johnson
authors.forename: M R
authors.initials: MR
authors.lastname: Costanzo
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000241:Adenosine / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D002648:Child; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000503:physiopathology* / Q000601:surgery; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology; D003643:Death; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006084:Graft Rejection / Q000503:physiopathology; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000494:pharmacology; D011237:Predictive Value of Tests; D011379:Prognosis; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional; D014652:Vascular Diseases / Q000503:physiopathology*; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014665:Vasodilator Agents; D005996:Nitroglycerin; D000241:Adenosine; D000109:Acetylcholine