title: Coronary flow velocity pattern and coronary flow reserve by contrast-enhanced transthoracic echocardiography predict long-term outcome in heart transplantation.
abstract: BACKGROUND
  We assessed coronary flow velocity pattern and coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) as markers of major adverse cardiac events (MACE) related to cardiac allograft vasculopathy (CAV) after heart transplantation (HT).
  
  
  RESULTS
  Deceleration time of diastolic flow velocity (DDT) and CFR were measured in the left anterior descending coronary artery (LAD) by CE-TTE in 66 consecutive HT patients (follow-up 19+/-5 months). CFR was calculated as the ratio of hyperemic to basal diastolic flow velocity. Angiographies were analyzed by a qualitative grading system; CAV was defined as changes grade II or higher. MACE were cardiac death, stent implantation, and heart failure. Patients with MACE had higher CAV incidence (P=0.004) and grade (P=0.008), shorter DDT (P=0.006), and lower CFR (P=0.008). A receiver-operating characteristic-derived DDT cutpoint < or = 840 ms (area under the curve 0.793; P=0.01) was 75% specific and 86% sensitive for predicting MACE, with positive predictive value (PPV) and negative predictive value (NPV) of 33% and 97%, respectively (P=0.002). A CFR cutpoint of < or =2.6 (area under the curve 0.746; P=0.01) was 62% specific and 91% sensitive for predicting MACE (PPV =32%, NPV =97%) (P=0.001). Patients with CFR < or = 2.6 and patients with DDT < or = 840 ms had a lower survival free from MACE (P=0.006 and P=0.009, respectively). By Cox regression, only a lower CFR predicted the risk of MACE (relative risk 3.1; 95% CI, 1.26 to 7.9; P=0.01).
  
  
  CONCLUSIONS
  In HT patients, shorter DDT and lower CFR by CE-TTE are reliable markers for CAV-related MACE. CFR is the main independent predictor of MACE.
authors.affiliation: Department of Cardiology , University of Padova, Padova, Italy. francescotona@hotmail.com
authors.forename: Francesco
authors.initials: F
authors.lastname: Tona
authors.forename: Alida L P
authors.initials: AL
authors.lastname: Caforio
authors.forename: Roberta
authors.initials: R
authors.lastname: Montisci
authors.forename: Antonio
authors.initials: A
authors.lastname: Gambino
authors.forename: Annalisa
authors.initials: A
authors.lastname: Angelini
authors.forename: Massimo
authors.initials: M
authors.lastname: Ruscazio
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Toscano
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Feltrin
authors.forename: Angelo
authors.initials: A
authors.lastname: Ramondo
authors.forename: Gino
authors.initials: G
authors.lastname: Gerosa
authors.forename: Sabino
authors.initials: S
authors.lastname: Iliceto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data; D019540:Area Under Curve; D001783:Blood Flow Velocity; D006328:Cardiac Catheterization; D003287:Contrast Media; D017023:Coronary Angiography; D003326:Coronary Circulation; D003971:Diastole; D018572:Disease-Free Survival; D004452:Echocardiography; D018618:Echocardiography, Doppler, Color; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000453:epidemiology; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D012680:Sensitivity and Specificity; D015607:Stents / Q000706:statistics & numerical data; D014184:Transplantation, Homologous; D016896:Treatment Outcome; D014657:Vasculitis / Q000000981:diagnostic imaging* / Q000453:epidemiology
chemical_list: D003287:Contrast Media