title: Simultaneous evaluation of myocardial blood flow, cardiac function and lung water content using [15O]H2O and positron emission tomography.
abstract: OBJECTIVE
  This study sought to evaluate an imaging approach using [15O]H2O and positron emission tomography (PET) for simultaneous assessment of myocardial perfusion, cardiac function and lung water content as a potential indicator of pulmonary oedema.
  
  
  METHODS
  Twenty-six subjects divided into two groups (group I, 13 patients with idiopathic dilated cardiomyopathy; group II, 13 healthy volunteers) underwent dynamic PET scanning after intravenous infusion of approximately 995 MBq [15O]H2O. In both groups, echocardiograms were performed after the PET studies. From the dynamic [15O]H2O data, lung water content (LWC) at equilibrium, myocardial blood flow (MBF), cardiac output (CO), stroke volume (SV) and stroke volume indexes (SVI) using the indicator dilution principle were determined.
  
  
  RESULTS
  LWC was 18% (p = 0.038) higher in patients than in controls. Global MBF did not differ significantly between the groups, but regional MBF values were significantly lower (p < 0.05) in the anterior and septal walls in the patient group. The results of the Passing-Bablok regression indicated the absence of a systematic difference between the two techniques. Bland-Altman analysis performed for each group (patients vs healthy controls) showed a non-significant bias (p > 0.1) of -0.02 +/- 0.82 vs -0.05 +/- 0.54 l/min (CO), -1.44 +/- 14.31 vs 1.70 +/- 10.56 ml/beat (SV) and 0.47 +/- 6.21 vs 0.30 +/- 5.02 ml/beat/m2 (SVI). The 95% limits of agreement were -1.62 to 1.59 vs -1.11 to 1.01 l/min (CO), -26.61 to 29.49 vs -22.39 to 18.99 ml/beat (SV) and -11.69 to 12.88 vs -9.53 to 10.14 ml/beat/m2 (SVI). Right ventricular CO was increased by 33% (p = 0.014) in the patient group as compared with normal controls.
  
  
  CONCLUSIONS
  Our results demonstrate that additional analysis of cardiac function and lung water content are feasible from the dynamic cardiac [15O]H2O PET studies acquired for myocardial perfusion. The parameters appear to work as expected. Further studies are warranted to elucidate the clinical value of these new parameters.
authors.affiliation: Turku PET Centre, Turku University Central Hospital, P.O. Box 52, 20521, Turku, Finland.
authors.forename: Alexandru
authors.initials: A
authors.lastname: Naum
authors.forename: Helena
authors.initials: H
authors.lastname: Tuunanen
authors.forename: Erik
authors.initials: E
authors.lastname: Engblom
authors.forename: Vesa
authors.initials: V
authors.lastname: Oikonen
authors.forename: Hannu
authors.initials: H
authors.lastname: Sipilä
authors.forename: Patricia
authors.initials: P
authors.lastname: Iozzo
authors.forename: Pirjo
authors.initials: P
authors.lastname: Nuutila
authors.forename: Juhani
authors.initials: J
authors.lastname: Knuuti
mesh_terms: D001834:Body Water / Q000378:metabolism*; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000378:metabolism*; D003326:Coronary Circulation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008168:Lung / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010104:Oxygen Radioisotopes; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D014867:Water
chemical_list: D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals; D014867:Water