title: Endocardial border delineation capability of a novel multimodal polymer-shelled contrast agent.
abstract: BACKGROUND
  A novel polymer-shelled contrast agent (CA) with multimodal and target-specific potential was developed recently. To determine its ultrasonic diagnostic features, we evaluated the endocardial border delineation as visualized in a porcine model and the concomitant effect on physiological variables.
  
  
  METHODS
  Three doses of the novel polymer-shelled CA (1.5 ml, 3 ml, and 5 ml [5 × 10(8) microbubbles (MBs)/ml]) and the commercially available CA SonoVue (1.5 ml [2-5 × 10(8) MBs/ml]) were used. Visual evaluations of ultrasound images of the left ventricle were independently performed by three observers who graded each segment in a 6-segment model as either 0 = not visible, 1 = weakly visible, or 2 = visible. Moreover, the duration of clinically useful contrast enhancement and the left ventricular opacification were determined. During anesthesia, oxygen saturation, heart rate, and arterial pressure were sampled every minute and the effect of injection of CA on these physiological variables was evaluated.
  
  
  RESULTS
  The highest dose of the polymer-shelled CA gave results comparable to SonoVue. Thus, no significant difference in the overall segment score distribution (2-47-95 vs. 1-39-104), time for clinically sufficient contrast enhancement (20-40 s for both) and left ventricular overall opacification was found. In contrast, when comparing the endocardial border delineation capacity for different regions SonoVue showed significantly higher segment scores for base and mid, except for the mid region when injecting 1.5 ml of the polymer-shelled CA. Neither high nor low doses of the polymer-shelled CA significantly affected the investigated physiological variables.
  
  
  CONCLUSIONS
  This study demonstrated that the novel polymer-shelled CA can be used in contrast-enhanced diagnostic imaging without influence on major physiological variables.
authors.affiliation: Department of Medical Engineering, School of Technology and Health, KTH Royal Institute of Technology, Alfred Nobels Allé 10, 141 52 Huddinge, Sweden. malinl@sth.kth.se.
authors.forename: Malin K
authors.initials: MK
authors.lastname: Larsson
authors.forename: Matilda
authors.initials: M
authors.lastname: Larsson
authors.forename: Greg
authors.initials: G
authors.lastname: Nowak
authors.forename: Gaio
authors.initials: G
authors.lastname: Paradossi
authors.forename: Lars-Åke
authors.initials: LÅ
authors.lastname: Brodin
authors.forename: Birgitta Janerot
authors.initials: BJ
authors.lastname: Sjöberg
authors.forename: Kenneth
authors.initials: K
authors.lastname: Caidahl
authors.forename: Anna
authors.initials: A
authors.lastname: Bjällmark
mesh_terms: D000818:Animals; D003287:Contrast Media; D004452:Echocardiography / Q000379:methods*; D004699:Endocardium / Q000000981:diagnostic imaging*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D045423:Microbubbles; D023421:Models, Animal; D011142:Polyvinyl Alcohol; D034421:Sus scrofa
chemical_list: D003287:Contrast Media; D011142:Polyvinyl Alcohol