[Feasibility of Single-Breath-Hold Compressed Sensing Real-Time Cine Imaging for Assessment of Ventricular Function and Left Ventricular Strain in Cardiac Magnetic Resonance].

Objective: To explore the feasibility of single-breath-hold compressed sensing real-time cine imaging (CS-cine) in the assessment of ventricular function and left ventricular (LV) strain. Methods: A total of 70 subjects were enrolled prospectively, and all subjects underwent cardiac magnetic resonance imaging (cardiac MRI) using both the standard steady-state free procession cine (sta-cine) acquisition and a prototype CS-cine sequence. For both CS-cine and sta-cine imaging, continuous short-axis cine images were acquired from the base to the apex to cover the entire left ventricle, and long-axis cine images including two-, three-, and four-chamber views were also acquired. The scanning range, number of slices, slice thickness and intervals were kept identical for the two cine images of the same participant. Subjective evaluation of the image quality was performed on all cine images. For both sequences, the conventional function parameters of the left and the right ventricles and LV strain values were assessed with post-processing software analysis. The cine image quality, conventional ventricular function parameters, and LV strain values were compared between the two cine groups and the differences were examined. Inter- and intraobserver agreements for CS-cine images were measured using intraclass correlation coefficient ( ICC). Bland-Altman analysis was performed to assess reproducibility between the two cine methods. Results: The median scanning time of CS-cine was 21 s versus 272 s for sta-cine ( P<0.001). The median image quality scores of two groups were significantly different, 4 points for sta-cine and 2 points for CS-cine ( P<0.001). Bi-ventricular end-diastolic volumes (EDV), stroke volume (SV) and ejection fraction (EF) were significantly smaller in CS-cine ( P<0.001). Nevertheless, no significant differences between the two groups in bi-ventricular ESV or LV mass were observed ( P>0.05). LV strain parameters, including the peak radial strain, peak circumferential strain and peak longitudinal strain derived from LV mid-ventricular slice, were significantly different in the two sequences ( P<0.001). Moreover, CS-cine-derived functional parameters and strain measurements have a good correlation with those of sta-cine (for RV function parameters, and left ventricular PLS, PCS values, more than 95% points fell within the limits of agreement [ LoA]; meanwhile, more than 91% points fell within the LoA for other parameters) and inter- and intraobserver agreements were strong ( ICC=0.88 to 0.99) for CS-cine. Conclusion: CS-cine can well realize the rapid acquisition of cine images for quantitative analysis of cardiac function, and the conventional ventricular function parameters and LV globalized strain values obtained from CS-cine imaging have good reproducibility.

Assessing right ventricular function in patients with hypertrophic cardiomyopathy with cardiac MRI: correlation with the New York Heart Function Assessment (NYHA) classification.

PURPOSE: To determine whether 3.0-T magnetic resonance imaging (MRI) could assess right ventricular (RV) function in patients with hypertrophic cardiomyopathy (HCM), and if this assessment is correlated with the New York Heart Function Assessment (NYHA) classification. MATERIALS AND METHODS: Forty-six patients with HCM and 23 normal individuals were recruited. Left and right ventricular function parameters including end-diastolic and end-systolic volumes (EDV, ESV), stroke volume (SV) and ejection fraction (EF) and dimensions were measured and compared using 3.0-T MRI. RV function parameters between HCM patients and controls were compared using independent sample t tests. A one way ANOVA test with Bonferroni correction was used to determine significant differences among different NYHA groups. Receiver operating characteristic analyses calculated the sensitivity and specificity of RV dysfunction on MRI for the prediction of HCM severity. RESULTS: Statistical analysis revealed significant differences of left ventricular (LV) and RV volumetric values and masses between the HCM patients and controls (all p<0.05). Within the HCM group, the simultaneously decreased maximum RVEDD correlated well with the LVEDD (r = 0.53; p<0.001). The function and dimension parameters among Class I to III were not determined to be significantly different (all p>0.05). However, significant differences between the Class IV and I-III groups (all P<0.0167) indicated that the diastolic and systolic function in both the RV and LV were impaired in Class IV patients. ROC analyses identified the EDV, ESV and EDD of both the LV and RV with a high sensitivity cutoff value to predict the HCM patients with severe heart failure (Class IV) with high sensitivity and specificity. CONCLUSIONS: RV involvements were comparable to those of LV global function impairments in patients with HCM. The presence of RV dysfunction and decreased dimension on the MRI helped to predict the severe symptomatic HCM with high sensitivity and specificity.

The regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy patients with or without left ventricular outflow tract obstruction: assessment with first-pass perfusion imaging using 3.0-T cardiac magnetic resonance.

PURPOSE: To assess regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy (HCM) patients with or without left ventricular outflow tract obstruction using 3.0-T cardiac magnetic resonance (CMR) first-pass perfusion imaging. MATERIALS AND METHODS: Forty-two HCM patients, including 25 HCM patients with left ventricular outflow tract obstruction (HOCM), 17 HCM patients without left ventricular outflow tract obstruction (NOHCM), and 14 healthy subjects underwent CMR. The left ventricular (LV) function, left ventricular end-diastolic wall thickness (EDTH), and diameter of left ventricular outflow tract (LVOT) were measured and calculated. Based on the signal-time curve of the first-pass myocardium perfusion imaging, perfusion parameters including upslope, time to peak, and peak intensity, were assessed and compared by using one-way analysis of variance and independent t tests. RESULTS: On the first-pass perfusion imaging, lower upslope and peak intensity and longer time to peak were found in HCM patients compared with normal subjects (all p<0.05). In contrast to the NOHCM group, the average time to peak of the HOCM group was increased (13.30 ± 4.82 s vs 16.28 ± 4.90 s, p<0.05), but first-pass perfusion upslope was reduced (4.96 ± 2.55 vs 2.58 ± 0.77, p<0.05). According to the bull's-eye model, the HOCM group's average thickness of basal segments was thicker than the NOHCM group, especially the anteroseptal, inferolateral, and anterior wall values, with a corresponding lower first-pass perfusion upslope than the NOHCM group (all p<0.05). A significant correlation was observed between first-pass perfusion upslope and LV EDTH (r=-0.551, p<0.001) and LVOT diameter (r=0.472, p<0.001). CONCLUSIONS: The regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy (HCM) patients with or without left ventricular outflow tract obstruction can be detected with first-pass perfusion CMR imaging.