Heart, Lung and Circulation

Evaluation of Right Ventricular Volume and Systolic Function – A Comparison of 2 and 3-Dimensional Echocardiography with Cardiac Magnetic Resonance

      Background: Cardiac magnetic resonance (CMR) is the gold standard for non-invasive assessment of right ventricular (RV) size and function, but is limited by its availability. Real time 3D echocardiography (RT3DE) is an emerging technology. We compared 2D and 3D echo with CMR for RV assessment in a prospective cohort.
      Method: Over a six month period, patients referred for CMR also underwent echocardiography on the same day. RV volumes and ejection fraction (EF) were measured on both RT3DE and CMR. On 2D echo, we measured RV area, fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE), peak tricuspid annular systolic velocity (RV S′) and peak tricuspid regurgitation velocity.
      Results: Thirty patients were recruited (mean age 40; 67% male). Three-dimensional image analysis was performed on 22 cases as image quality was suboptimal in eight. RT3DE analysis of RV end diastolic and end systolic volumes (RVEDV and RVESV) correlated well with CMR (RVEDV r = 0.83, p < 0.001; RVESV r = 0.87, p < 0.001). Correlation between RT3DE and CMR measurement of RVEF was weaker (r = 0.60, p= 0.003). Two-dimensional measurements were suitable for analysis in all 30 patients. There was strong correlation between 2D RV area and CMR RV volume (RVEDV r= 0.90, p < 0.001; RVESV r = 0.94, p < 0.001), and weaker correlation between CMR RVEF and both RVFAC (r= 0.56, p < 0.001) and TAPSE (r= 0.48, p= 0.01).
      Conclusion: RT3DE is comparable to CMR for assessment of RV volume and EF. Two-dimensional measurement of RV area correlates with CMR RV volume, which may be helpful in patients with poor RT3DE image quality.