Three-dimensional measurement of LV and RV dimensions using prospective self-gating for simultaneous compensation of cardiac and respiratory motion

Purpose

To compare three-dimensional (3D) balanced steady-state free precession (SSFP), prospective self-gating technique [1] without ECG triggering and breath-holding for the assessment of left ventricular (LV) and right ventricular (RV) function in the heart in comparison to standard 2D, multiple breath-hold SSFP cine imaging.

Methods

Data were acquired in 15 subjects (10 volunteers, 5 patients) using a 1.5 T system with a five element cardiac array coil. In each subject a standard multi-slice, multi-breathhold 2D cine SSFP sequence was performed with complete ventricular coverage. Additionally, a three-dimensional cine sequence with prospective self-gating [1] with complete ventricular coverage was acquired during free breathing. LV and RV end-systolic volume (ESV) and end-diastolic volume (EDV) and LV mass were calculated for each method. With both imaging techniques, a patient-based analysis of image quality was performed with grading on a four-point scale, referring to the visibility of the endocardial border (excellent (4), good (3), moderate (2) and nondiagnostic (1)).

Results

Good agreement between LVEDV, LVESV, LV mass, LVEF, RVEDV, RVESV, and RVEF calculated for the standard 2D and the 3D prospective self-gating method (concordance coefficients 0.99, 0.99, 0.99, 0.90, 0.95, 0.95 and 0.91, respectively). The mean bias (95% confidence interval (CI) for each parameter was; LVEDV: -0.3% (-5.2 to 4.6), LVESV: 0.3% (-5.4 to 6.0), LV mass: -0.8% (-8.3 to 6.8), LVEF: -0.2% (-2.7 to 2.4), RVEDV: 4.5% (-9.6 to 18.6), RVESV: 3.8% (-11.2 to 18.7), RVEF: 1.0% (-4.7 to 6.7). The overall image quality score for prospective self-gating (2.7 ± 0.8) was lower when compared to standard SSFP (3.9 ± 0.4; p < 0.01). Figure 1 shows representative images from one patient.

Figure 1

End-diastolic (ED) frame of the left and right ventricle (mid-ventricular slice in short-axis orientation); left: multi-breath-hold, standard SSFP, right: free breathing prospective self-gating.

Discussion

Three-dimensional, free-breathing, prospective self-gating MRI enabled accurate assessment of LV and RV quantitative parameters when compared to standard multi-slice, multi-breathhold SSFP cine imaging. Image quality with prospective self-gating was rated lower relative to the reference ECG triggered, multiple breathhold scans due to lower image contrast between blood and myocardium and residual motion artefacts.