title: Low-dose dobutamine radionuclide ventriculography for prediction of myocardial viability: quantitative analysis of regional left ventricular function.
abstract: BACKGROUND
  It is important to distinguish viable myocardium from necrotic tissue in order to decide upon therapy in patients with ischemic heart disease.
  
  
  OBJECTIVE
  We verified the hypothesis that quantitative analysis of regional left ventricular function using low-dose dobutamine radionuclide ventriculography (RNV) can sensitively predict myocardial viability and compared its usefulness with thallium-201 (201Tl) single-photon emission computed tomography (201Tl-SPECT).
  
  
  METHODS
  Radionuclide ventriculography at rest and during low-dose dobutamine infusion (5 micrograms/kg/min), 201Tl-SPECT, and coronary angiography were performed in 51 subjects with severe ischemia-related stenosis of coronary arteries and 3 subjects without coronary artery disease. 201Tl uptake was assessed as normal (control), low perfusion (LP), or defect. We compared the response of regional function to dobutamine with the regional 201Tl uptake. The accuracy of both methods for identifying viable myocardium was investigated in 17 patients who underwent successful coronary revascularization, with a resulting improvement in wall motion.
  
  
  RESULTS
  The increase in regional ejection fraction (delta r-EF) in response to dobutamine was significantly greater in the control (12 +/- 6%) and LP (16 +/- 11%) regions than in the defect (5 +/- 10%) regions. The increase in one-third regional ejection fraction (delta r-1/3EF) was also significantly higher in the control (14 +/- 7%) and LP (10 +/- 8%) regions than in the defect regions (5 +/- 6%). We defined myocardial viability as a delta r-EF > 5% or a delta r-1/3EF > 2%. The sensitivity and specificity of the delta r-EF for identification of myocardial viability were 91.4 and 55.5%, respectively. The sensitivity and specificity of the delta r-1/3EF were 91.4 and 66.6%, respectively; the corresponding values for 201Tl SPECT were 74.2 and 77.8%.
  
  
  CONCLUSIONS
  Low-dose dobutamine RNV with quantitative analysis of regional left ventricular function was more sensitive for identification of viable myocardium than 201Tl-SPECT.
authors.affiliation: Department of Internal Medicine, University of Tsukuba, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Takeyasu
authors.forename: S
authors.initials: S
authors.lastname: Watanabe
authors.forename: R
authors.initials: R
authors.lastname: Ajisaka
authors.forename: K
authors.initials: K
authors.lastname: Eda
authors.forename: M
authors.initials: M
authors.lastname: Toyama
authors.forename: K
authors.initials: K
authors.lastname: Sakamoto
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Yamanouchi
authors.forename: T
authors.initials: T
authors.lastname: Masuoka
authors.forename: T
authors.initials: T
authors.lastname: Takeda
authors.forename: Y
authors.initials: Y
authors.lastname: Itai
authors.forename: Y
authors.initials: Y
authors.lastname: Sugishita
authors.forename: I
authors.initials: I
authors.lastname: Yamaguchi
mesh_terms: D000368:Aged; D002316:Cardiotonic Agents / Q000008:administration & dosage*; D004280:Dobutamine / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015635:Radionuclide Ventriculography; D012680:Sensitivity and Specificity; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D016277:Ventricular Function, Left
chemical_list: D002316:Cardiotonic Agents; D013794:Thallium Radioisotopes; D004280:Dobutamine