title: The practical value of technetium-99m-MIBI SPET to differentiate between ischemic and non-ischemic heart failure presenting with exertional dyspnea.
abstract: OBJECTIVE
  We aimed to differentiate ischemic heart failure (HF) from non-ischemic HF in patients presenting with non-acute onset exertional dyspnea using technetium-99m methoxyisobutylisonitrile gated single photon emission tomography ((99m)Tc-MIBI gSPET) imaging.
  
  
  METHODS
  One hundred and seventy nine consecutive patients with exertional dyspnea without concomitant chest pain referred to (99m)Tc-MIBI gSPET imaging were included in this study. All patients had a newly diagnosed HF with reduced ejection fraction (HFrEF). Imaging findings were compared between ischemic HF and non-ischemic HF groups.
  
  
  RESULTS
  Of the 179 patients, 127 had ischemic HF and 52 had non-ischemic HF. There was no difference between ischemic and non-ischemic groups in terms of age, gender, body mass index, any smoking history, diabetes mellitus, history of hypertension and hyperlipidemia. Global dysfunction of left ventricle was more common in non-ischemic HF group than ischemic HF group (82.7% vs 41.7% respectively, P<0.001). Presence of severe (3+/4+) ischemia and large perfusion defect were higher in ischemic HF group compared to non-ischemic HF group (45.7% vs 15.4%, P<0.001 and 23.6% vs 3.8%, P=0.003, respectively). Summed stress score (SSS), summed rest score and summed difference score were higher in ischemic HF group compared to non-ischemic HF group (P<0.001, P<0.001, and P=0.021, respectively). In multivariate analysis, absence of global dysfunction (P<0.001, OR=10.338, 95%CI: 3.937-27.405) and SSS (P<0.001, OR=1.208, 95%CI: 1.090-1.339) were the independent predictors of ischemic HF. Absence of global dysfunction had 58.3% sensitivity and 86.7% specificity for diagnosis of ischemic HF at gSPET imaging in patients presenting with newly diagnosed HF and exertional dyspnea without concomitant chest pain (AUC=0.705, 95%CI: 0.632-0.771, P<0.001), whereas SSS>8 had 65.4% sensitivity and 75.0% specificity (AUC=0.732, 95%CI: 0.661-0.795, P<0.001).
  
  
  CONCLUSIONS
  Absence of global dysfunction and SSS on SPET imaging were the independent predictors of ischemic etiology of HF presenting with dyspnea without concomitant chest pain. These findings had a low sensitivity, but acceptable specificity.
authors.affiliation: Department of Cardiology, Heart Center, Cumhuriyet University, PC 58140, Sivas, Turkey. obeton@cumhuriyet.edu.tr.
authors.forename: Osman
authors.initials: O
authors.lastname: Beton
authors.forename: Ozge
authors.initials: O
authors.lastname: Kurmus
authors.forename: Lale Dinc
authors.initials: LD
authors.lastname: Asarcikli
authors.forename: Buket
authors.initials: B
authors.lastname: Alibazoglu
authors.forename: Haluk
authors.initials: H
authors.lastname: Alibazoglu
authors.forename: Mehmet Birhan
authors.initials: MB
authors.lastname: Yilmaz
mesh_terms: D002637:Chest Pain / Q000150:complications; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000150:complications*; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications*; D005082:Physical Exertion; D012189:Retrospective Studies; D013318:Stroke Volume; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D017256:Technetium Tc 99m Sestamibi