Clinical Feasibility Study Of Real-time Cardiac Magnetic Resonance Cine Imaging With Compressed Sensing Combined With Motion Correctio

Objectives:To prospectively evaluate the feasibility and biventricular assessment accuracy of a free-breathing cardiac cine imaging technique(RTCSCineMoCo)combined with highly accelerated real-time acquisition,compressed sensing(CS)reconstruction,and retrospective fully automated non-rigid motion correction.Methods:We evaluated 80 patients scheduled for clinical cardiac magnetic resonance imaging.Cardiac cine images of the same long-axis and short-axis stacks were acquired using three techniques(1.SegBH:standard segmented cine with retrospective ECG gating and breath-hold;2.RTCSCineMoCo;3.RTCSCine:single-shot cardiac cine with compressed sensing real-time imaging)at 3.0 T.Image quality was evaluated using a qualitative 5-point Likert scale and the European CMR registry standardized criteria,and edge sharpness was measured.Quantitative parameters including left(LV)and right ventricle(RV)ejection fractions(EF),end-diastolic volumes(EDV),end-systolic volumes(ESV),stroke volumes(SV),and LV mass(LVM)were measured and compared.Results:RTCSCineMoCo and SegBH had equivalent image quality scores(4.4±0.7 vs 4.2±0.8,P=0.066),while RTCSCine had a significantly lower image quality score than SegBH(4.0±0.8 vs 4.2±0.8,P=0.031).In a quantitative analysis,RTCSCineMoCo and SegBH yielded similar measurements for all parameters(all P>0.05),while the majority of RTCSCine parameters were significantly different compared with SegBH,except for LVEDV.Conclusion:RTCSCineMoCo is a promising method for robust free-breathing cardiac cine imaging,achieving better image quality and more precise quantitative analysis results for both ventricles compared with RTCSCine.Background:To evaluate the feasibility and accuracy of free-breathing cardiac cine MR imaging(RTCSCineMoCo)combined with highly accelerated real-time acquisition,compressed sensing(CS)reconstruction,and fully automated non-rigid motion correction for left ventricular(LV)strain analysis.Traditional 2D segmented cine imaging with retrospective ECG gating and breath-hold(SegBH)was used as the reference standard and compared with free-breathing single-shot cardiac cine with compressed sensing real-time imaging(RTCSCine).Methods:A total of 67 patients scheduled for clinical cardiac MR imaging were included.Cine images were acquired using three techniques(1.SegBH,2.RTCSCineMoCo,3.RTCSCine)consecutively at 3.0 T.LV functional parameters,including ejection fraction(EF),end-diastolic volume(EDV),end-systolic volume(ESV),stroke volumes(SV),and LV mass(LVM)were measured and compared.Strain parameters including global radial(GRS),circumferential(GCS),and longitudinal(GLS)strain as well as corresponding time to peak strain(TPS)were computed by MR feature tracking and compared.Subgroup analyses were performed according to heart rate(HR),and LVEF.Results:All quantitative parameters of LV function and strain measured by RTCSCineMoCo(r≥0.766)and RTCSCine(r≥0.712)showed strong correlations with SegBH(all P<0.001).LV functional parameters were not statistically different between RTCSCineMoCo and SegBH(all P>0.05),but an overestimation of LVESV and underestimation of LVEF and LVM were observed using RTCSCine(all P<0.001).GRS,GCS,and GLS by RTCSCineMoCo and RTCSCine were significantly different than those by SegBH(all P<0.05).All TPS values by RTCSCineMoCo showed no significant differences(all P>0.05)compared with SegBH,but TPS in longitudinal directions(TPSL)by RTCSCine was significantly different(P=0.011).There were no significant differences for GRS or GCS between RTCSCineMoCo and SegBH in patients with HR<70 bpm or LVEF<50%.GRS by RTCSCineMoCo showed similar results compared to SegBH in patients with pulmonary hypertension.Conclusions:RTCSCineMoCo is a promising method for robust FB cardiac cine imaging,achieving more precise quantitative analytic results for LV function compared with RTCSCine.RTCSCineMoCo mildly underestimated GRS,GCS,and GLS,but showed smaller bias compared to RTCSCine in LV strain analysis.Objective:To evaluate the feasibility and accuracy of free-breathing cardiac cine MR imaging(RTCSCineMoCo)combined with compressed sensing,highly accelerated realtime acquisition,and retrospective fully automated non-rigid motion correction for right ventricular(RV)function and strain analysis in patients with pulmonary hypertension(PH).Methods:Suspected or confirmed PH patients clinically scheduled for CMR assessment were enrolled in Department of Radiology of Peking Union Medical College Hospital of Chinese Academy of Medical Sciences from January 2020 to April 2021.All enrolled patients received the standard 2D segmented acquisition with retrospective ECG gating and breath-hold(SegBH)and RTCSCineMoCo.Image quality was evaluated using a qualitative 5-point Likert scale and the European CMR registry standardized criteria,and edge sharpness was measured.RV function and strain were measured and compared.Results:Forty patients were enrolled in this study.The mean scan times of SegBH and RTCSCineMoCo were 143±42 s and 115±24 s,respectively(P<0.05).The general subjective image quality scores of RTCSCineMoCo and SegBH were 4.4±0.7 and 4.1±0.8,respectively(P<0.05),and the standardized criteria image quality scores of RTCSCineMoCo and SegBH based on the European CMR registry standardized criteria were 0.125±0.404 and 0.425±0.844,respectively(P<0.05).There was no significant difference by edge sharpness measurement between SegBH and RTCSCineMoCo(0.064±0.133 vs 0.065±0.139,P>0.05).There were no significant differences in the assessment of RV functional parameters between SegBH and RTCSCineMoCo,including RV ejection fraction(EF),end-diastolic volumes(EDV),end-systolic volumes(ESV),stroke volumes(SV),and RV mass(RVM),additionally,all RV functional parameters showed strong correlations(r=0.966-0.992)between the two cine techniques.RV myocardial strain including global longitudinal strain(GLS),global circumferential strain(GCS),and global radial strain(GRS)derived from RTCSCineMoCo were significantly lower than those by SegBH(all P<0.05).GCS and GRS showed strong correlations(r=0.895 for GCS;r=0.908 for GRS),but GLS showed a weak correlation(r=0.564)between the two cine techniques.Subgroup analysis showed that GLS,GCS,and GRS measured with RTCSCineMoCo were significantly underestimated in patients with mild PH(WHO function class I-II,Group 1)but no significant differences in patients with severe PH(WHO function class Ⅲ-Ⅳ,Group 2)when compared with those measured with SegBH.All parameters for both techniques showed good intra-observer and inter-observer agreement.Conclusions:Compared with SegBH,RTCSCineMoCo can shorten image acquisition time,obtain equivalent or even better image quality,and achieve precise quantitative analytic results for RV function in patients with PH,and obtain accurate strain evaluation in patients with severe PH.