Abstract 13079: Evaluation of Ventricular Volume and Mass using 4D echocardiography on a Fetal-Sized Heart: An in vivo study
Background: Ventricular volume and mass are often used to aid diagnosis and assessment of cardiac disorders as well as evaluation of the treatment of defects. This study evaluated the feasibility and accuracy of non-gated full volume 4D echocardiography in determining ventricular volume and mass using an in vivo fetal heart model.
Methods: Five open chest instrumented rabbits were studied. Four sonomicrometry (sono) crystals were implanted on the left ventricular (LV) surface of the heart to acquire volume (A). Full volume 4D image loops were acquired at each state with an X6-1 matrix probe on a Phillips IU22 ultrasound system. After acquiring baseline image data, each rabbit was subjected to saline bolus at two different volumes (2ml/kg; 4ml/kg); inferior vena cava (IVC) and ascending aorta (AAO) ligations were performed to simulate rapid changes in ventricular volume. Echo and sono data were acquired for each experimental state, allowing time for the heart to completely recover, and real baseline images to be recorded between states. At the conclusion of the study, the rabbits were sacrificed and heart mass determined by displacement in a graduated cylinder. Echo-based imaging data were analyzed by QLabTM Advanced General Imaging 3D Quantification (GI-3DQ) program (B). Sonomicrometry data were analyzed by SonoVIEW.
Results: At each study state, sono-derived LV and right ventricular (RV) volume values were smaller than echo-derived volumes, but all showed strong linear correlations (all R2> 0.85). Highest volume values were observed at 4ml/kg saline bolus and in the AAO ligation state; whereas IVC ligation showed lowest volume values (C). Mass was accurately determined at each state with a high coefficient of determination (LV mass: R2=0.98; RV mass: R2=0.91) (D, E).
Conclusions: With its high temporal and spatial resolution, non-gated 4D imaging with QLabTM GI-3DQ software demonstrates the ability to reliably quantify ventricular volumes and mass for small hearts.
- © 2013 by American Heart Association, Inc.