Abstract 18799: Correlation of 2D Strain for Intraoperative Assessment of Right Ventricular Mechanics with Admittance Catheters in Juvenile Pigs
Background: Surgical manipulations such as opening the chest and volume loading have the potential to alter ventricular function. There is paucity of data on the effects of such manipulations on right ventricular (RV) function. We measured tricuspid annular plane excursion (TAPSE) and RV strain by two-dimensional echo (2DE) speckle tracking to assess systolic and diastolic RV function in juvenile pigs under conditions that simulate the intraoperative environment. These were compared to simultaneously obtained parameters of RV function using admittance catheters.
Methods: Epicardial 2DE was performed (Philips iE33) in 6 juvenile pigs (19-23kg). TAPSE and systolic and diastolic 2D RV longitudinal strain (LS) and strain rate (LSR) (TomTec Image Arena, TomTec, Germany) were measured offline. RV systolic and diastolic pressure/volume data was acquired simultaneously using admittance catheters (Scisense Inc, Canada) under conditions including closed chest, open chest and volume loading. Comparisons were made using Pearson’s correlation coefficient; heart rate and end-diastolic pressure (EDp) were stratified into tertiles to evaluate for threshold effects.
Results: We obtained 15 sets of paired data (Table). There was a high correlation between RVLS and EDp; this increased at lower EDp, at higher heart rates and with chest open vs. closed. There was high correlation between RVLS and TAPSE; this correlation was higher at higher heart rates, with the chest open and after a fluid bolus. Systolic LSR, diastolic SR and diastolic LSR did not correlate with catheter-derived measures of RV function.
Conclusions: 2D RV strain correlates well with RVEDp in conditions that simulate the intraoperative environment. We speculate that the increased correlations after sternotomy may be related to alterations in RV compliance, possibly related to the removal of pericardial restraint. The effect of altered loading conditions on echo-cath correlations bears further study.
Author Disclosures: S.R. Ramlogan: None. R.A. Hopkins: None. S.F. Kaine: None. E. Buse: None. S.P. Goudar: None. H. Dai: None. G.S. Shirali: None.
- © 2014 by American Heart Association, Inc.