title: Usefulness of progressive inhomogeneity of myocardial perfusion and chronotropic incompetence in detecting cardiac allograft vasculopathy: evaluation with dobutamine thallium-201 myocardial SPECT.
abstract: BACKGROUND
  The aim of the study was to investigate the value of longitudinal follow-up of dobutamine thallium-201 single photon emission tomography ((201)Tl SPECT) in the development of significant cardiac allograft vasculopathy (CAV) after orthotopic heart transplantation.
  
  
  METHODS
  We studied 38 cardiac recipients (mean age 57 +/- 12 years) who underwent at least two follow-up dobutamine (201)Tl SPECT since January 1998. All patients had normal coronary angiography and normal left ventricular function initially.
  
  
  RESULTS
  After 2.3 +/- 1.8 years, 12 patients developed significant CAV and there were 4 cardiac deaths (1 died suddenly). Of the 99 scans retrospectively analyzed, patients with significant CAV had elevated values of inhomogeneity score, lung/heart ratio (LHR) at stress and lower left ventricular ejection fraction (all p < 0.05). The higher values of inhomogeneity were significantly correlated with higher stress LHR (r = 0.301, p = 0.021), and lower ejection fraction (r = -0.379, p < 0.001). Progressive inhomogeneity was noted in all heart recipients, and more rapid, although statistically insignificant, in patients who developed significant CAV. Ten patients had inadequate chronotropic response to dobutamine infusion up to 40 mug/kg/min in the follow-up studies. The late onset of chronotropic incompetence was an independent predictor of CAV development (p = 0.03).
  
  
  CONCLUSIONS
  Progressive inhomogeneity of myocardial perfusion, higher lung uptake at stress and chronotropic incompetence assessed by dobutamine (201)Tl myocardial SPECT provide incremental diagnostic value in detecting significant CAV.
authors.affiliation: Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei.
authors.forename: Yen-Wen
authors.initials: YW
authors.lastname: Wu
authors.forename: Ruoh-Fang
authors.initials: RF
authors.lastname: Yen
authors.forename: Chii-Ming
authors.initials: CM
authors.lastname: Lee
authors.forename: Yi-Lwun
authors.initials: YL
authors.lastname: Ho
authors.forename: Shoei-Shen
authors.initials: SS
authors.lastname: Wang
authors.forename: Ron-Bin
authors.initials: RB
authors.lastname: Hsu
authors.forename: Nai-Kuan
authors.initials: NK
authors.lastname: Chou
authors.forename: Por-Jau
authors.initials: PJ
authors.lastname: Huang
mesh_terms: D000318:Adrenergic beta-Agonists; D000368:Aged; D004280:Dobutamine; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology*; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D015425:Myocardial Reperfusion; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology* / Q000401:mortality; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013318:Stroke Volume / Q000502:physiology; D016019:Survival Analysis; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D014184:Transplantation, Homologous; D016896:Treatment Outcome
chemical_list: D000318:Adrenergic beta-Agonists; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes; D004280:Dobutamine