Cardiac Magnetic Resonance Imaging Parameters Research Articles

Kiosk 10R-FB-01 - Prognostic Value of Cardiac Magnetic Resonance Imaging Parameters in Patients with Primary Mitral Regurgitation Undergoing Mitral Valve Intervention

Kiosk 10R-FB-01 - Prognostic Value of Cardiac Magnetic Resonance Imaging Parameters in Patients with Primary Mitral Regurgitation Undergoing Mitral Valve Intervention

Fractal analysis: Left ventricular trabecular complexity cardiac MRI adds independent risks for heart failure with preserved ejection fraction in participants with end-stage renal disease

PurposeTo measure left ventricular (LV) trabecular complexity by fractal dimension (FD) in patients with end-stage renal disease (ESRD), and assess whether FD was an independent risk factor for heart failure with preserved ejection fraction (HFpEF), or a significant predictor for adverse outcome in this population. MethodsThe study retrospectively enrolled 104 participants with ESRD who underwent 3.0 T cardiac magnetic resonance imaging (MRI) from June 2018 to November 2020. LV trabeculation was quantified with fractal analysis of short-axis cine slices to estimate the FD. Logistic regression analyses were used to evaluate FD and cardiac MRI parameters and to find independent risk predictors. Cox proportional hazard regression was used to investigate the association between FD and MACE. ResultsLV FD was higher in in the HFpEF group than those in the non-HFpEF group, with the greatest difference near the base of the ventricle. Age, minimum left atrial volume index, and LV mean basal FD were independent predictors for HFpEF in patients with ESRD. Combining the mean basal FD with typical predictive factors resulted in a C-index (0.902 vs 0.921), which was not significantly higher. Same improvements were found for net reclassification improvement [0.642; 95% confidence interval (CI), 0.254–1.029] and integrated discrimination index (0.026; 95% CI, 0.008–0.061). Participants with a LV global FD above the cutoff value (1.278) had higher risks of MACE in ESRD patients. ConclusionsLV trabecular complexity measured by FD was an independent risk factor for HFpEF, and a significant predictor for MACE among patients with ESRD.

Cardiac magnetic resonance imaging in mortality risk stratification of patients with pulmonary hypertension

Aim. To compare cardiac magnetic resonance imaging (MRI) parameters with known prognosis determinants in patients with pulmonary hypertension (PH).Material and methods. This prospective single-center study included 60 patients with PH aged 21-72 years. Cardiac MRI, right heart catheterization, echocardiography, N-terminal pro-brain natriuretic peptide (NT-proBNP) and 6-minute walk test (6MWT) were assessed at baseline.Results. Significant correlations between invasive hemodynamic parameters, NTproBNP and cardiac MRI parameters were confirmed. There were no significant correlations between the right ventricular (RV) contractility, RV volume and 6MWT distance, the functional class of PH. Cardiac MRI values allowed us to reliably separate patients at low risk from those at intermediate and high risk according to the 2015 ESC/ERS score. According to multivariate regression analysis, the right ventricular end systolic volume index >54 ml/m2 (hazard ratio, 0,2; 95% confidence interval, 0,05-0,9; p=0,004) and class 3-4 PH (hazard ratio, 0,2; 95% confidence interval, 0,07-0,8; p=0,026) remained independent predictors of mortality.Conclusion. The use of cardiac MRI in low-risk patients can significantly improve the early detection of right ventricular myocardial dysfunction and contribute to the timely optimization of PH-specific therapy. During monitoring patients with PH, cardiac MRI has the potential to reduce the need for repeated invasive investigations.

Pulmonary transit time as a marker of diastolic dysfunction in Takotsubo syndrome

To evaluate the pulmonary transit time (PTT) and its derived parameters using cardiac magnetic resonance imaging (CMRI) as markers of diastolic dysfunction in Takotsubo syndrome (TS) and its relationship with transthoracic echocardiography and CMRI parameters. Twenty-two patients with TS, who exhibited diastolic dysfunction as assessed by transthoracic echocardiography, were enrolled retrospectively and the PTT, pulmonary transit time index (PTTI), and pulmonary blood volume index (PBVI) were evaluated using first-pass CMRI. PTT was calculated as the number of cardiac cycles required for a bolus of contrast agent to move from the right ventricle (RV) to the left ventricle (LV), whereas PTTI represents the PTT interval corrected for the heart rate. Finally, PBVI was calculated as the product of PTTI, and RV stroke volume indexed for body surface area. Normal references of PTT, PTTI, and PBVI were evaluated in a cohort of 20 age- and sex-matched healthy controls. Compared with healthy subjects, TS patients showed significantly higher PTT, PTTI, and PBVI (p=0.0001, p=0.0001, and p=0.002, respectively). Using multivariable logistic regression, PBVI provided the best differentiation between TS and controls (AUC 0.84). PBVI was significantly associated with the index of diastolic dysfunction and left atrial strain parameters. In addition, PBVI demonstrated a significant correlation with global T2 mapping (r=0,520, p=0,019). PTT and the derived parameters, as assessed using first-pass CMRI, are potential tools for assessing LV diastolic dysfunction in patients with TS.

Quantitative cardiac MRI parameters for assessment of myocarditis in children and adolescents: a systematic review and meta-analysis

To evaluate the role of quantitative cardiac magnetic resonance imaging (CMRI) parameters in myocarditis, including acute and chronic myocarditis (AM and CM), for children and adolescents. PRISMA principles were followed. PubMed, EMBASE, Web of Science, Cochrane Library, and grey literature were searched. The Newcastle-Ottawa Scale (NOS) and the Agency for Healthcare Research and Quality (AHRQ) checklist were utilised for quality assessment. Quantitative CMRI parameters were extracted and a meta-analysis was performed in comparison with healthy controls. The overall effect size was measured as the weighted mean difference (WMD). Ten quantitative CMRI parameters of seven studies were analysed. Compared with the control group, the myocarditis group reported longer native T1 relaxation time (WMD=54.00, 95% confidence interval [CI]: 33.21,74.79, p<0.001), longer T2 relaxation time (WMD=2.13, 95% CI: 0.98, 3.28, p<0.001), increased extracellular volume (ECV; WMD=3.13, 95% CI: 1.34,4.91, p=0.001), elevated early gadolinium enhancement (EGE) ratio (WMD=1.47, 95% CI: 0.65,2.28, p<0.001), and increased T2-weighted ratio (WMD=0.43, 95% CI: 0.21,0.64, p<0.001). The AM group had longer native T1 relaxation times (WMD=72.02, 95% CI: 32.78,111.27, p<0.001), increased T2-weighted ratios (WMD=0.52, 95% CI: 0.21,0.84 p=0.001), and impaired left ventricular ejection fractions (LVEF; WMD=-5.84, 95% CI: -9.69, -1.99, p=0.003). Impaired LVEF (WMD=-2.24, 95% CI: -3.32, -1.17, p<0.001) was observed in the CM group. Statistical differences can be observed in some CMRI parameters between patients with myocarditis and healthy controls; however, apart from native T1 mapping, there were no large differences in other parameters between two groups, which may reveal the limited benefit of CMRI in assessing myocarditis in children and adolescents.

Detection of haemodynamic obstruction in hypertrophic cardiomyopathy using the sub-aortic complex: a cardiac MRI and Doppler study

To investigate the "sub-aortic complex (SAC)", a new cardiac magnetic resonance imaging (CMRI)-derived parameter, for the evaluation of left ventricular (LV) outflow tract (LVOT) obstruction in patients with hypertrophic cardiomyopathy (HCM), compared with conventional CMRI parameters and Doppler echocardiography. A total of 157 consecutive patients with HCM were recruited retrospectively. The patients were divided into two groups, 87 with LVOT obstruction and 70 without obstruction. The SAC was defined as a specific anatomical SAC affecting the LVOT, which were measured on the LV three-chamber steady-state free precession (SSFP) cine image at the end-systolic phase. The relations between the existence and severity of obstruction and SAC index (SACi) were evaluated using Pearson's correlation coefficient, receiver operating characteristic (ROC) curves, and logistic regression. The SACs were significantly different between the obstructive and non-obstructive groups. The ROC curves indicated that the SACi was able to discriminate obstructive and non-obstructive patients with the best predictive accuracy (AUC=0.949, p<0.001). The SACi was an independent predictor of LVOT obstruction and there was a significant negative correlation between resting LVOT pressure gradient and SACi (r=0.72 p<0.001). In the subgroup of patients with or without severe basal septal hypertrophy, the SACi was still able to predict LVOT obstruction with excellent diagnostic accuracy (AUC=0.944 and 0.948, p<0.001, respectively). The SAC is a reliable and straightforward CMRI marker for assessing LVOT obstruction. It is more effective than CMRI two-dimensional flow in diagnosing the severity of obstruction in patients with HCM.

Pharmacoinvasive Strategy in Elderly Up to 75 Years or Non-Elderly: Analysis of Biochemical and Cardiac Magnetic Resonance Imaging Parameters.

Pharmacoinvasive strategy is an alternative when primary percutaneous coronary intervention (PCI) is not feasible. This study aimed to evaluate the effects of early pharmacoinvasive strategy on the infarct size and left ventricular ejection fraction in elderly and non-elderly patients. The role of inflammatory markers was also examined. Patients (n=223) with ST segment elevation myocardial infarction (STEMI) were prospectively included and submitted to pharmacological thrombolysis in the first six hours, and underwent coronary angiogram and PCI when necessary, in the first 24 hours. Blood samples were collected in the first day (D1) and after 30 days (D30). Cardiac magnetic resonance imaging (cMRI) was performed at D30. Significance was set at p<0.05. Elderly and non-elderly patients showed similar percentage of infarcted mass (13.7 [6.9-17.0] vs. 14.0 [7.3-26.0], respectively, p=0.13) (median [interquartile range]). However, elderly patients had better left ventricular ejection fraction (53 [45-62] vs. 49 [39-58], p=0.025). Titers of interleukin (IL)1beta, IL-4, IL-6, and IL-10 did not differ between D1 and D30, but elderly patients had higher titers for IL-18 at D1 and D30. Absolute numbers of B and T lymphocytes were similar in both groups at D1 and D30, but elderly patients had higher neutrophil/lymphocyte ratio at D30. Multivariate linear regression analysis of cMRI outcomes in the whole population showed that the independent predictors were not different between elderly and non-elderly patients. Pharmacoinvasive strategy in elderly patients was associated with small differences in inflammatory parameters, similar infarct size and better left ventricular function than non-elderly patients.

T1 mapping of the myocardium and liver in the single ventricle population.

Fontan associated liver disease (FALD) is an increasingly recognized complication of the single ventricle circulation characterized by hepatic venous congestion leading to hepatic fibrosis. Within the Fontan myocardium, fibrotic myocardial remodeling may occur and lead to ventricular dysfunction. Magnetic resonance imaging (MRI) T1 mapping can characterize both myocardial and liver properties. The aim of this study was to compare myocardial and liver T1 between single ventricle patients with and without a Fontan and biventricular controls. A retrospective study of 3 groups of patients: 16 single ventricle patients before Fontan (SVpre 2 newborns, 9 pre-Glenn, 5 pre-Fontan, 31% single right ventricle [SRV]), 16 Fontans (56% SRV) and 10 repaired d-transposition of the great arteries (TGA). Native modified Look-Locker inversion T1 times were measured in the myocardium and liver. Cardiac MRI parameters, myocardial and liver T1 values were compared in the three groups. Correlations were assessed between liver T1 and cardiac parameters. Myocardial T1 was higher in SVpre (1,056 ± 48ms) and Fontans (1,047 ± 41ms) compared to TGA (1,012 ± 48ms, P < 0.05). Increased liver T1 was found in both SVpre (683 ± 82ms) and Fontan (727 ± 49ms) patients compared to TGA patients (587 ± 58ms, P < 0.001). There was no difference between single left ventricle (SLV) versus SRV myocardial or liver T1. Liver T1 showed moderate correlations with myocardial T1 (r = 0.48, confidence interval [CI] 0.26-0.72) and ejection fraction (r = -0.36, CI -0.66-0.95) but not with other volumetric parameters. Increased liver T1 at both pre- and post-Fontan stages suggests there are intrinsic liver abnormalities early in the course of single ventricle palliation. Increased myocardial T1 and its relationship to liver T1 suggest a combination of edema from passive venous congestion and/or myocardial fibrosis occurring in this population. Liver T1 may provide an earlier marker of liver disease warranting further study.

Cardiac magnetic resonance imaging parameters show association between myocardial abnormalities and severity of chronic kidney disease.

Chronic kidney disease patients have increased risk of cardiovascular abnormalities. This study investigated the relationship between cardiovascular abnormalities and the severity of chronic kidney disease using cardiac magnetic resonance imaging. We enrolled 84 participants with various stages of chronic kidney disease (group I: stages 1-3, n = 23; group II: stages 4-5, n = 20; group III: hemodialysis patients, n = 41) and 32 healthy subjects. The demographics and biochemical parameters of the study subjects were evaluated. All subjects underwent non-contrast cardiac magnetic resonance scans. Myocardial strain, native T1, and T2 values were calculated from the scanning results. Analysis of covariance was used to compare the imaging parameters between group I-III and the controls. The left ventricular ejection fraction (49 vs. 56%, p = 0.021), global radial strain (29 vs. 37, p = 0.019) and global circumferential strain (-17.4 vs. -20.6, p < 0.001) were significantly worse in group III patients compared with the controls. Furthermore, the global longitudinal strain had a significant decline in group II and III patients compared with the controls (-13.7 and -12.9 vs. -16.2, p < 0.05). Compared with the controls, the native T1 values were significantly higher in group II and III patients (1,041 ± 7 and 1,053 ± 6 vs. 1,009 ± 6, p < 0.05), and T2 values were obviously higher in group I-III patients (49.9 ± 0.6 and 53.2 ± 0.7 and 50.1 ± 0.5 vs. 46.6 ± 0.5, p < 0.001). The advanced chronic kidney disease stage showed significant positive correlation with global radial strain (r = 0.436, p < 0.001), global circumferential strain (r = 0.386, p < 0.001), native T1 (r = 0.5, p < 0.001) and T2 (r = 0.467, p < 0.001) values. In comparison with the group II patients, hemodialysis patients showed significantly lower T2 values (53.2 ± 0.7 vs. 50.1 ± 0.5, p = 0.002), but no significant difference in T1 values (1,041 ± 7 vs. 1,053 ± 6). Our study showed that myocardial strain, native T1, and T2 values progressively got worse with advancing chronic kidney disease stage. The increased T1 values and decreased T2 values of hemodialysis patients might be due to increasing myocardial fibrosis but with reduction in oedema following effective fluid management. ChiCTR2100053561 (http://www.chictr.org.cn/edit.aspx?pid=139737&htm=4).

The Role of MR Assessments of Cardiac Morphology, Function, and Tissue Characteristics on Exercise Capacity in Well-Functioning Older Adults.

The relationship between resting cardiac indices and exercise capacity in older adults was still not well understood. New developments in cardiac magnetic resonance imaging (MRI) enable a much fuller assessment of cardiac characteristics. To assess the association between exercise capacity and specific aspects of resting cardiac structure, function, and tissue. Cross-sectional study. A total of 112 well-functioning older adults (mean age 69 years, 52 men). All participants underwent 3.0 T MRI, using scan protocols including balanced steady-state free precession cine sequence, modified look-locker inversion recovery, and T2-prepared single-shot balanced steady-state free precession. Demographic and geriatric characteristics were collected. Blood samples were assayed for lipid and glucose related biomarkers. All participants performed a symptom-limited cardiopulmonary exercise test to achieve peakVO2 . Cardiac MRI parameters were measured with semi-automatic software by S.Y., an 18-year experienced radiologist. Demographic, geriatric characteristics and MR measurements were compared among quartiles of peakVO2, with different methods according to the data type. Spearman's partial correlation and least absolute shrinkage selection operator regression were performed to select significant MR features associated with peakVO2 . Mediation effect analysis was conducted to test any indirect connection between age and peakVO2 . A two-sided P value of <0.05 was defined statistical significance. Epicardial fat volume, left atrial volume indexed to height, right ventricular end-systolic volume indexed to body surface area and global circumferential strain (GCS) were correlated with peakVO2 (regression coefficients were -0.040, -0.093, 0.127, and 0.408, respectively). Mediation analysis showed that the total effect of peakVO2 change was 43.6% from the change of age. The proportion of indirect effect from epicardial fat volume and GCS were 11.8% and 15.1% in total effect, respectively. PeakVO2 was associated with epicardial fat volume, left atrial volume, right ventricular volume and GCS of left ventricle. 4 TECHNICAL EFFICACY: Stage 5.

Impaired aortic strain and distensibility by cardiac MRI in children with chronic kidney disease

Renal disease is associated with increased arterial stiffness. The aim was to investigate the effect of renal disease on regional aortic strain and distensibility in children with chronic kidney disease (CKD) by cardiac magnetic resonance imaging (MRI). The study included 30 children with CKD on hemodialysis, and ten healthy control subjects. Using cardiac MRI, maximal and minimal aortic areas were measured in axial cine steady state free precision images at the ascending aorta, proximal descending, and aorta at diaphragm. Regional strain and distensibility were calculated using previously validated formulas. Second reader aortic areas measurements were used to assess inter-observer agreement. Ascending aorta strain was significantly reduced in patients (38.4 ± 17.4%) compared to the control group (56.1 ± 17%), p-value 0.011. Ascending Aorta distensibility was significantly reduced in patients (9.1 ± 4.4 [× 10−3 mm Hg−1]) compared to the control group (13.9 ± 4.9 [× 10−3 mm Hg−1]), p-value 0.006. Strain and distensibility were reduced in proximal descending aorta and aorta at diaphragm but did not reach statistical significance. Only ascending aorta strain and distensibility had significant correlations with clinical and cardiac MRI parameters. Inter-observer agreement for strain and distensibility was almost perfect or strong in the three aortic regions. Aortic strain and distensibility by cardiac MRI are important imaging biomarkers for initial clinical evaluation and follow up of children with CKD.

Diagnostic Value of 11C-PIB PET/MR in Cardiac Amyloidosis.

BackgroundThe thioflavin T derivative, 11C-Pittsburgh-B (PIB), is used for Alzheimer's disease imaging because it specifically binds to β-amyloid protein deposits in the brain. The aim of this study was to estimate the diagnostic value of combined 11C-PIB positron emission tomography/magnetic resonance (PET/MR) in cardiac amyloidosis (CA).MethodsWe enrolled 23 heart failure patients with suspected CA based on echocardiographic and electrocardiograph findings. All patients underwent cardiac 11C-PIB PET/MR and non-cardiac biopsy within one week. We also enrolled eight healthy volunteers that underwent cardiac 11C-PIB PET/MR as a control group. The cardiac magnetic resonance (CMR) protocol included cine imaging, late gadolinium enhancement (LGE), and native and post-contrast T1 mapping. Extracellular volume (ECV) was measured using pre- and post-contrast T1 mapping images. LVEF, IVSD, LVPW, LVmass, LVESV, LVEDV, native T1 value, ECV, and maximum uptake of myocardial tissue-to-blood background ratio (TBR) values were obtained from PET/MR images in all patients and healthy subjects.ResultsThirteen out of twenty-three heart failure patients were clinically diagnosed with CA. The remaining 10 patients were CA-negative (non-CA patient group). Twelve of the thirteen CA patients showed diffuse transmural LGE patterns, whereas LGE was either absent or patchy in the non-CA patients. The diagnostic sensitivity and specificity of TBRmax were 92.3 and 100%, respectively, at a cut-off value of 1.09. Several CMR imaging parameters (LVEF, IVSD, LVmass, LVEDV, LVESV, LVPW, native T1 value and ECV) and TBR showed significant differences between CA patients, non-CA patients, and healthy controls (P < 0.05). Native T1 mapping values positively correlated with TBRmax values in CA and non-CA patients (r = 0.38, P = 0.0004).Conclusions11C-PIB PET/MRI is a valuable tool for the accurate and non-invasive diagnosis of CA because it distinguishes CA patients from non-CA patients and healthy subjects with high specificity and sensitivity. Moreover, native T1 mapping values positively correlated with TBRmax values in CA and non-CA patients. In the future, larger cohort studies are necessary to confirm our findings.

Limitations of cardiothoracic ratio derived from chest radiographs to predict real heart size: comparison with magnetic resonance imaging

BackgroundCardiothoracic ratio (CTR) in chest radiographs is still widely used to estimate cardiac size despite the advent of newer imaging techniques. We hypothesise that a universal CTR cut-off value of 50% is a poor indicator of cardiac enlargement. Our aim was to compare CTR with volumetric and functional parameters derived from cardiac magnetic resonance imaging (MRI).Methods309 patients with a chest radiograph and cardiac MRI acquired within a month were reviewed to assess how CTR correlates with multiple cardiac MRI variables: bi-ventricular EDV (absolute and indexed to body surface area), EF, indexed total heart volume and bi-atrial areas. In addition, we have also determined CTR accuracy by creating multiple ROC curves with the described variables.ResultsAll cardiac MRI variables correlate weakly but statistically significantly with CTR. This weak correlation is explained by a substantial overlap of cardiac MRI parameters in patients with normal and increased CTR. For all variables, CTR was only mildly to moderately better than a chance to discriminate cardiac enlargement (AUC 0.6–0.7). Large CTR values (> 55%) are specific but not sensitive, while low CTR values (< 45%) are sensitive but not specific. Values in between are not sensitive nor specific.ConclusionsCTR correlates weakly with true chamber size assessed by gold standard cardiac MRI and has a weak discriminatory power. Thus, clinical decisions based on intermediate CTRs (45–55%) should be avoided. Large CTRs (> 55%) are likely indicative of true heart chamber enlargement. Low CTRs (< 45%) are likely indicative of normal heart size.

Quantification of myocardial amyloid deposition in tafamidis-treated patients with transthyretin amyloid cardiomyopathy

Abstract Background Tafamidis kinetically stabilizes the tetrameric form of transthyretin (TTR) and thus may halt disease progression in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). However, the effect of tafamidis treatment on the progression of myocardial amyloid deposition is still unclear. Methods In our explorative analysis, we aimed to investigate the treatment effect of tafamidis on myocardial amyloid deposition measured by myocardial standardized uptake value (SUV) peak and SUV retention index using quantitative single-photon emission computed tomography/computed tomography (SPECT/CT) of the thorax and to observe its association with clinical parameters. Therefore, clinical, laboratory, imaging, and SPECT/CT examinations were performed in twenty consecutive ATTR-CM patients who started treatment with tafamidis 61mg, both at baseline and at a median of 6 months. Results Main results are summarized in Table 1. In brief, we observed a significant reduction of mean myocardial SUV peak (baseline: 15.50 vs. follow-up: 11.61, p&amp;lt;0.001) and mean SUV retention index (5.64 vs. 3.58, p=0.001) after treatment with tafamidis (Figure 1A). Interestingly, a higher percentage decrease in the SUV retention index is more likely to be associated with clinical benefit, with a threshold of −30% distinguishing between patients who respond clinically (n=12) and those who do not (n=8, Figure 1B). Clinical response is demonstrated by improvement in exertional dyspnea (NYHA class III: 83.3% vs. 41.7%, p=0.047) and mean functional capacity as measured by 6-minute walk distance (349.5m vs. 356.7m, p=0.736). Cardiac biomarkers analysis showed a clear reduction in median NT-proBNP levels in the responder cohort (2765.0 pg/mL vs. 1904.0 pg/mL, p=0.041) compared to an increase in the non-responder cohort (1825.0 pg/mL vs. 1944.0 pg/mL, p=0.208; cohort comparison: p=0.026, Figure 1C). Echocardiographic findings revealed improvement in mean left ventricular (LV) strain (−12.0% vs. −13.5%, p=0.049) and mean LV ejection fraction (LVEF, 48.5% vs. 52.7%, p=0.287) in the responder cohort, while significant deterioration in mean LV function (LV strain: −13.9 vs. −10.5, p=0.035; LVEF: 53.2% vs. 46.5%, p=0.012) was observed in the non-responder cohort, with an additional substantial deterioration in right ventricular (RV) function as measured by tricuspid annular plane systolic excursion (TAPSE, mean, BL: 19.2mm vs. FU: 12.6mm, p=0.037) in those patients. These results are consistent with changes in the LV and RV function in cardiac magnetic resonance imaging parameters in each of the two cohorts. Conclusion Treatment with tafamidis in patients with ATTR-CM results in a significant reduction in myocardial amyloid deposition as measured by the SUV retention index, with a threshold of −30% distinguishing patients who respond clinically from those who do not. However, a larger patient sample is needed to verify these results. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Pfizer Inc.

The Effect of Adiposity on Cardiovascular Function and Myocardial Fibrosis in Patients With Duchenne Muscular Dystrophy.

BackgroundPatients with Duchenne muscular dystrophy (DMD) develop cardiomyopathy because of a dystrophin deficiency causing fibrofatty replacement of the myocardium. Corticosteroid use and mobility limitations place these patients at risk for increased adiposity. We sought to determine the association of adiposity with cardiovascular dysfunction in patients with DMD.Methods and ResultsThis was a retrospective review of patients with DMD who underwent both cardiac magnetic resonance imaging and dual‐energy x‐ray absorptiometry within 1 year. The cardiac magnetic resonance imaging parameters included left ventricular ejection fraction and the presence of late gadolinium enhancement (LGE positive [LGE+]). The adiposity indices, measured by dual‐energy x‐ray absorptiometry, included percentage of body fat, whole body fat mass indexed to height, and body mass index. A total of 324 patients were identified. Fifty‐two percent had LGE+, and 36% had cardiac dysfunction (left ventricular ejection fraction <55%). Patients with cardiac dysfunction had higher whole body fat mass indexed to height and body mass index on univariate analysis (mean difference between patients with and without cardiac dysfunction: +2.9 kg/m, P=0.001; and +1.5 kg/m2, P=0.03, respectively). whole body fat mass indexed to height remained independently associated with cardiac dysfunction on multivariable analysis after adjusting for age, LGE+, and corticosteroid duration. High whole body fat mass indexed to height and percentage of body fat were associated with LGE+ on univariate analysis (mean difference between patients with and without LGE+: +2.0 kg/m, P=0.02; and +2.4%, P=0.02, respectively). Using multivariable analysis, including age and cardiac dysfunction, high percentage of body fat remained independently associated with LGE+.ConclusionsThis study demonstrates an independent association of adiposity with cardiac dysfunction and LGE+ in patients with DMD. Preventing adiposity may mitigate the later development of ventricular dysfunction in DMD.

Cardiac Magnetic Resonance Follow-Up of Children After Pediatric Inflammatory Multisystem Syndrome Temporally Associated With SARS-CoV-2 With Initial Cardiac Involvement.

BackgroundPediatric inflammatory multisystem syndrome temporally associated with SARS‐CoV‐2 (PIMS‐TS) is an inflammatory disease occurring in a small minority of children a few weeks after acute infection. Cardiac manifestations are common, but little is known about the potentially persistent heart changes after PIMS‐TS.PurposeTo analyze the frequency and type of myocardial complications of PIMS‐TS with initial cardiac involvement assessed with cardiac magnetic resonance imaging (MRI), including parametric imaging, performed 3 months after hospitalization.Study TypeRetrospective.PopulationNineteen consecutive children (median age 10 years, interquartile range (IQR) 10–15 years, 74% male).Field Strength/SequenceBalanced steady state free precession (bSSFP, cine imaging), modified Look‐Locker (T1 mapping), T2‐prepared bSSFP (T2‐mapping), dark‐blood T2‐weighted turbo spin echo with fat suppression and phase sensitive inversion recovery (late gadolinium enhancement (LGE)) sequences at 1.5 T.AssessmentPatients were scanned after a median of 99 days (IQR 89–104 days) from the diagnosis. MR data were reviewed by three independent observers, with 13, 2, and 5 years' experience in cardiac MRI. Pre‐ and post‐contrast T1, T2, extra‐cellular volume, and T2 signal intensity (T2 SI) ratio were calculated. Diagnosis of acute myocarditis was based on modified Lake Louise criteria. Cardiac MRI parameters were compared, where possible, to previously published pediatric normal values.Statistical TestsInterclass correlation coefficient and Bland–Altman repeatability analysis. A P‐value <0.05 was considered statistically significant.ResultsDespite cardiac involvement including decreased left ventricular ejection fraction (LVEF) (median LVEF = 47%, IQR 43%–53%) and increased troponin I (median 101 ng/mL, IQR 50–661 ng/mL) during hospitalization, there were no persistent cardiac changes observed in cardiac MR at follow‐up. All patients had normal size and function of the left ventricle and normal precontrast T1 and T2 relaxation times. There were no signs of LGE. Persistent, mild pericardial effusion (8–9 mm) was found in three (16%) patients.Data ConclusionThere were no persistent changes on cardiac MRI in a group of children approximately 3 months post hospitalization due to PIMS‐TS with cardiac involvement. This supports the hypothesis that cardiac involvement during PIMS‐TS is a form of transient inflammatory response rather than direct and potentially persistent injury from the virus.Level of Evidence4Technical EfficacyStage 3

CMR assessment of right ventricular remodeling after transcatheter therapy for severe tricuspid regurgitation

Abstract Funding Acknowledgements Type of funding sources: Private hospital(s). Main funding source(s): Helios Clinical Research Institute Background/Introduction Patients with severe tricuspid regurgitation (TR) are characterized from severe dilatation and negative remodeling of the right heart chambers causing functional right ventricular (RV) failure and increased mortality and morbidity. The transcatheter tricuspid edge-to-edge repair (TTVR) is a new treatment option associated with symptom improvement and reduced hospitalization. The cardiac magnetic resonance imaging (CMRI) remains the gold standard for evaluating the right ventricular morphology and function and could be a useful in assessing the RV reverse remodeling after TTVR. The Tricuspid Regurgitation REgistry (TRuE) is an ongoing national prospective register of patients with severe TR that aims to identify morphofunctional parameters of the right heart chambers related to improve outcomes after TTVR. Purpose The present is a subanalysis of patients with serial CMRI examinations recruited in the ongoing prospective TRuE registry. Methods After excluding patients with intracardiac RV leads, seven patients (age 70 ±12 years) with completed thirty-day follow up were included in the present analysis. Retrospective gated steady state free precession cine images were acquired in the long and short-axis views covering the entirety of both ventricles. Aortic and pulmonary flow data were acquired with a flow-sensitive gradient echo sequence. Assessment of left ventricular (LV) and RV volumes was performed manually in the short-axis cine images (Circle Cardiovascular Imaging, Calgary, Alberta, Canada). The TR fraction was calculated as: ({total RV stroke volume (SV) – total pulmonary forward flow}/total RVSV) × 100. All volumes and flow measurements were indexed for body surface area and expressed in ml/m2. The ratio between the diameter of pulmonary artery (PA) and ascending aorta (AA) was used as indirect measurement of pulmonary arterial hypertension (PAH). CMRI parameters assessing TR quantification, RV morphology and function were analyzed at baseline and follow-up with Fisher´s test or paired t-test. Results At thirty days there was a significant reduction of the TR fraction (45% to 20%, p &amp;lt; 0.001), RV dilatation (RV-end diastolic volume (EDV): 106 ± 12ml/m2 to 86 ± 9.4ml/m2, p = 0.002, RV- end sistolic volume (ESV):55 ± 6.5 to 43 ± 6.6ml, p = 0.003) and improvement of function (RVEF: 47 ± 3.6 to 53 ± 2.4 %, p = 0.006). On the left heart side, there was an improvement of LV filling, with increased LVEDV and LVESV and of the LVSV (36 ± 5.3 to 41 ± 3.7ml/m2, p = 0.040), causing an improvement of the cardiac index (2.2 ± 0.9 l/min/m2 to 2.9 ± 0.7 l/min/m2; p = 0.019. Furthermore, the PA/AA ratio improved significantly (0.91 ± 0.15 to 0.81 ± 0.14, p = 0.006). Conclusion TTVR is associated with positive reverse remodeling of the RV with reduction of dilatation, PAH and function improvement.

Evaluation of the relationship between ventricular function and serum growth differentiation factor-15 levels in patients with operated tetralogy of Fallot.

Growth differentiation factor-15 is a novel biomarker of increasing importance in cardiovascular diseases. This study aimed to evaluate the relationship between ventricular measurements assessed by cardiac magnetic resonance imaging (MRI) and serum growth differentiation factor-15 levels in children with surgically corrected tetralogy of Fallot. Serum growth differentiation factor-15 levels were measured in 40 patients (mean age: 15.2 ± 2.9 years; 52.5% male; 87.5% NYHA I). End-diastolic volume index, end-systolic volume index, and ejection fractions of both ventricles and pulmonary regurgitation fraction were measured on cardiac MRI. The correlation between growth differentiation factor-15 levels and cardiac MRI parameters of the patients was investigated. Also, growth differentiation factor-15 levels of the patients were compared with healthy controls since reference values have not been determined in children. The mean growth differentiation factor-15 level was 254.9 ± 6.3 pg/ml in the patient group. There was no correlation between growth differentiation factor-15 levels and cardiac MRI parameters in patients. Also, there was no significant difference in growth differentiation factor-15 levels between the patients and control groups. The serum levels of growth differentiation factor-15 were uncorrelated with ventricular size, function, and pulmonary regurgitation fraction assessed by cardiac MRI in children with operated tetralogy of Fallot. Moreover, growth differentiation factor-15 levels were not different in these patients from healthy children.

Heterozygous Cystic Fibrosis Transmembrane Regulator Gene Missense Variants Are Associated With Worse Cardiac Function in Patients With Duchenne Muscular Dystrophy.

BackgroundDuchenne muscular dystrophy (DMD) is a neuromuscular disorder caused by mutations within the dystrophin gene. DMD is characterized by progressive skeletal muscle degeneration and atrophy and progressive cardiomyopathy. It has been observed the severity of cardiomyopathy varies in patients with DMD.Methods and ResultsA cohort of male patients with DMD and female DMD carriers underwent whole exome sequencing. Potential risk factor variants were identified according to their functional annotations and frequencies. Cardiac function of 15 male patients with DMD was assessed by cardiac magnetic resonance imaging, and various cardiac magnetic resonance imaging parameters and circulating biomarkers were compared between genotype groups. Five subjects carrying potential risk factor variants in the cystic fibrosis transmembrane regulator gene demonstrated lower left ventricular ejection fraction, larger left ventricular end‐diastolic volume, and higher NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) levels compared with 10 subjects who did not carry the potential risk factor variants (P=0.023, 0.019 and 0.028, respectively).ConclusionsThis study revealed heterozygous cystic fibrosis transmembrane regulator gene missense variants were associated with worse cardiac function in patients with DMD. The cystic fibrosis transmembrane regulator gene may serve as a genetic modifier that accounts for more severe cardiomyopathy in patients with DMD, who would require more aggressive management of the cardiomyopathy.

Quantitative Clinical Cardiac Magnetic Resonance Imaging.

Cardiac magnetic resonance imaging (MRI) represents the established reference standard method for the assessment of cardiac function and non-invasive evaluation of myocardial tissue in a variety of clinical questions, wherein quantification of cardiac parameters gains growing diagnostic and differential-diagnostic importance. This review aims to summarize established and newly emerging quantitative parameters, which are assessed in routine cardiac MRI. Interrelations and interdependencies between metrics are explained, and common factors affecting quantitative results are discussed. The review is based on a PubMed literature research using the search terms "cardiac magnetic resonance" and "quantification", "recommendations", "quantitative evaluation/assessment", "reference method", "reference/normal values", "pitfalls" or "artifacts" published between 2000-2019. Quantitative functional, phase contrast, and perfusion imaging, as well as relaxation time mapping techniques give opportunity for assessment of a large number of quantitative cardiac MRI parameters in clinical routine. Application of these techniques allows for characterization of function, morphology and perfusion of the heart beyond visual analysis of images, either in primary evaluation and comparison to normal values or in patients' follow-up and treatment monitoring. However, with implementation of quantitative parameters in clinical routine, standardization is of particular importance as different acquisition and evaluation strategies and algorithms may substantially influence results, though not always immediately apparent. · Clinical cardiac MRI provides numerous functional and morphological quantitative parameters.. · Quantitative cardiac MRI enables assessment of diffuse and global myocardial alterations.. · Standardized data acquisition/evaluation is the prerequisite for diagnostic use of quantitative cardiac MRI parameters.. · Reiter U, Reiter C, Kräuter C et al. Quantitative Clinical Cardiac Magnetic Resonance Imaging. Fortschr Röntgenstr 2020; 192: 246 - 256.