Insight Into the Interventricular Communication and Surrounding Structures in the Double Outlet Right Ventricle by Real-time Transthoracic Three-dimensional Echocardiography

  • Akio Inage, University of Alberta and Stollery Children`s Hospital, Canada
  • Ken Takahashi, Stollery Children's Hospital, University of Alberta, Canada
  • Ivan Rebeyka, Stollery Children's Hospital, University of Alberta, Canada
  • David Ross, Stollery Children's Hospital, University of Alberta, Canada
  • Jeffrey Smallhorn, Stollery Children's Hospital, University of Alberta, Canada

    • Objective: To assess the incremental value of real-time transthoracic three-dimensional echocardiography (RT3DE), over standard two-dimensional echocardiography (2DE) in the double outlet right ventricle (DORV).
    Background: The interventricular communication (IC) size which is crucial to the management of DORV is different from the “hole” closed by the surgeon (“surgical hole”).
    Methods: We measured end diastolic (ED) and end systolic (ES) area of the IC and “surgical hole” by RT3DE and 2DE for 21 patients with a median age of 0.4 years (0 day - 8 years). As well, we determined the relationship of the tricuspid valve (TV) to the IC.
    Results: We could not obtain an orthogonal image to measure “surgical hole” by 2DE in 8 cases. The mean ED and ES IC area/body surface area (BSA) (n=21) was 7.5 +/- 5.2 and 4.8 +/- 4.2 cm2/m2 by RT3DE and 3.2 +/- 1.8 and 1.7 +/- 1.1 cm2/m2 by 2DE respectively. The mean ED and ES “surgical hole” area/BSA (n=13) was 12.5 +/- 4.3 and 8.1 +/- 3.6 cm2/m2 by RT3DE and 5.7 +/- 2.4 and 3.5 +/- 1.8 cm2/m2 by 2DE respectively. 2DE tended to underestimate the IC and “surgical hole” size than RT3DE (P value ranges: 0.003 to 0.0003). The precise relationship of TV attachments in the vicinity of the IC were readily determined by RT3DE, but not by 2DE.
    Conclusion: RT3DE provides useful and additive information, and offers simulated intraoperative visualization of true interventricular communication and the “surgical hole” in DORV as well as the surrounding structures.