title: Predicting the response to cardiac resynchronization therapy using 99mTc-tetrofosmin myocardial scintigraphy in patients with drug-refractory heart failure: additional value of the washout of 99mTc-tetrofosmin.
abstract: OBJECTIVE
  A lack of response to cardiac resynchronization therapy (CRT) has been reported in 20-40% of heart failure patients with left ventricular (LV) dyssynchrony who underwent treatment based on the established guidelines. The study aimed to investigate the relationship between (99m)Tc-tetrofosmin ((99m)Tc-TF) myocardial scintigraphy and the response to CRT.
  
  
  METHODS
  Twenty-one patients with drug-refractory heart failure who underwent CRT were evaluated. All patients underwent (99m)Tc-TF myocardial scintigraphy before and after CRT. Single-photon emission computed tomography images of (99m)Tc-TF were acquired at 30 min and 3 h after injection and were used to determine the total defect score (TDS) and washout score (WOS). The change in the LV volume and ejection fraction (ΔLVEF) and relative reduction in left ventricular end-systolic volume (%ΔLVESV) were calculated as an index of LV functional recovery after CRT. Response to CRT was considered to have occurred when ΔLVEF was greater than 15% or when ΔLVEF was greater than 5% and %ΔLVESV was greater than 15%.
  
  
  RESULTS
  Significant differences were observed between the patients who responded to CRT (the responder group, 13 patients) and the nonresponder group (eight patients) for both early and delayed TDS and WOS (P<0.05). Moreover, there was a good correlation between early TDS before CRT and both ΔLVEF and %ΔLVESV (P<0.01) and an excellent correlation between WOS before CRT and both ΔLVEF and %ΔLVESV (P<0.01).
  
  
  CONCLUSIONS
  Evaluating the washout of (99m)Tc-TF in addition to myocardial perfusion before CRT using (99m)Tc-TF myocardial scintigraphy might be useful in drug-refractory heart failure patients.
authors: aDepartment of Internal Medicine, Division of Cardiovascular and Respiratory Medicine, Kobe University Graduate School of Medicine bKobe University Graduate School of Health Sciences, Kobe cHyogo Brain and Heart Center, Himeji, Japan.
authors: Mayumi
authors: M
authors: Shigeru
authors: Sei
authors: S
authors: Fujiwara
authors: Sachiko
authors: S
authors: Takamine
authors: Akihiro
authors: A
authors: Yoshida
authors: Hiroya
authors: H
authors: Kawai
authors: Hideyuki
authors: H
authors: Shiotani
authors: Ken-Ichi
authors: K
authors: Hirata
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D003198:Computer Simulation; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000628:therapy*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008657:Metabolic Clearance Rate; D008955:Models, Cardiovascular; D009943:Organophosphorus Compounds / Q000493:pharmacokinetics*; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D016896:Treatment Outcome
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin