0000000000009076
AUTHOR
Massimo Lombardi
Preferential patterns of myocardial iron overload by multislice multiecho T2* CMR in thalassemia major patients.
T*(2) multislice multiecho cardiac MR allows quantification of the segmental distribution of myocardial iron overload. This study aimed to determine if there were preferential patterns of myocardial iron overload in thalassemia major. Five hundred twenty-three thalassemia major patients underwent cardiac MR. Three short-axis views of the left ventricle were acquired and analyzed using a 16-segment standardized model. The T*(2) value on each segment was calculated, as well as the global value. Four main circumferential regions (anterior, septal, inferior, and lateral) were defined. Significant segmental variability was found in the 229 patients with significant myocardial iron overload (glob…
Feasibility, reproducibility, and reliability for the T*2 iron evaluation at 3 T in comparison with 1.5 T
This study aimed to determine the feasibility, reproducibility, and reliability of the multiecho T * 2 Magnetic resonance imaging technique at 3 T for myocardial and liver iron burden quantification and the relationship between T * 2 values at 3 and 1.5 T. Thirty-eight transfusion-dependent patients and 20 healthy subjects were studied. Cardiac segmental and global T * 2 values were calculated after developing a correction map to compensate the artifactual T * 2 variations. The hepatic T * 2 value was determined over a region of interest. The intraoperator and interoperator reproducibility for T * 2 measurements at 3 T was good. A linear relationship was found between patients' R (1000/T * …
Multicenter validation of the magnetic resonance t2* technique for segmental and global quantification of myocardial iron
Purpose To assess the transferability of the magnetic resonance imaging (MRI) multislice multiecho T2* technique for global and segmental measurement of iron overload in thalassemia patients. Materials and Methods Multiecho T2* sequences were installed on six MRI scanners. Five healthy subjects (n = 30) were scanned at each site; five thalassemia major (TM) patients were scanned at the reference site and were rescanned locally (n = 25) within 1 month. T2* images were analyzed using previously validated software. Results T2* values of healthy subjects showed intersite homogeneity. On TM patients, for global heart T2* values the correlation coefficient was 0.97, coefficients of variation (CoV…
Myocardial fibrosis by delayed enhancement cardiovascular magnetic resonance and HCV infection in thalassemia major patients.
Abstract Abstract 4265 Introduction. Delayed enhancement (DE) cardiac magnetic resonance (CMR) technique with intravenous administration of gadolinium (Gd) chelates contrast agents is the only validated non-invasive approach for detecting myocardial fibrosis (Mahrholdt H et al, Eur Heart J 2005). This technique has been confirmed safe in patients with hemoglobinopathies (Meloni A et al, Haematologica 2009). In thalassemia major (TM), myocardial fibrosis has been detected using the DE technique and a positive correlation with anti-HCV antibodies has been described (Pepe A et al, Heart 2009). However, HCV-induced cardiomyopathy is still controversial (Matsumori A et al. J Card Fail 2006). The…
Prospective Comparison on Cardiac Iron and Liver Iron by MR In Thalassemia Major Patients Treated with Combination Deferipron–Desferrioxamine Versus Deferipron and Desferrioxamine In Monoterapy
Abstract Abstract 5164 Introduction: Using T2* MR a randomised placebo controlled study from Sardinia demonstrated combination therapy with deferiprone and desferrioxamine (DFP+DFO) significantly more effective than DFO in improving myocardial iron. One non-randomised study from Sardinia and one observational study from Greece seem to confirm for DFP+DFO therapy the most rapid clearance of cardiac iron. No data are available in literature about prospective comparisons on cardiac iron and function and liver iron in TM patients treated with DFP+DFO versus DFP and DFO in monotherapy. The aim of this multi-centre study was to assess prospectively in a large clinical setting the efficacy of the …
Influence of preload and afterload on stroke volume response to low-dose dobutamine stress in patients with non-ischemic heart failure: a cardiac MR study.
Lack of increase in left ventricular (LV) stroke volume (SV) during low-dose dobutamine stress (LDD) is attributed to exhausted cardiac contractile reserve in failing heart. However, the role of the afterload and preload in SV changes is underestimated. The aim of the study was to investigate the effects of LDD on preload reserve and afterload in patients with non-ischemic heart failure.58 patients (age 62 years) underwent LDD (up to 20μg/kg/min) using cardiac magnetic resonance.LV-SV increased by 27% in 24 patients (p0.001) (SV+), while decreased by 19% in 22 patients (p0.001) (SV-). The LDD-to-rest reduction in preload, as defined by LV end-diastolic volume (EDV), was more pronounced in S…
Cardiac and hepatic iron and ejection fraction in thalassemia major: Multicentre prospective comparison of combined Deferiprone and Deferoxamine therapy against Deferiprone or Deferoxamine Monotherapy
Background: Due to the limited data available in literature, the aim of this multi-centre study was to prospectively compare in thalassemia major (TM) patients the efficacy of combined deferiprone (DFP) and deferoxamine (DFO) regimen versus either DFP and DFO in monotherapy by cardiovascular magnetic resonance (CMR) over a follow up of 18 months. Methods: Among the first 1135 TM patients in the MIOT (Myocardial Iron Overload in Thalassemia) network, we evaluated those who had received either combined regimen (DFO + DFP, N=51) or DFP (N=39) and DFO (N=74) monotherapies between the two CMR scans. Iron overload was measured by T2* multiecho technique. Biventricular function parameters were qua…
Improved T2* assessment in liver iron overload by magnetic resonance imaging.
In the clinical MRI practice, it is common to assess liver iron overload by T2* multi-echo gradient-echo images. However, there is no full consensus about the best image analysis approach for the T2* measurements. The currently used methods involve manual drawing of a region of interest (ROI) within MR images of the liver. Evaluation of a representative liver T2* value is done by fitting an appropriate model to the signal decay within the ROIs vs. the echo time. The resulting T2* value may depend on both ROI placement and choice of the signal decay model. The aim of this study was to understand how the choice of the analysis methodology may affect the accuracy of T2* measurements. A softwar…
Evaluation of the efficacy of oral deferiprone in beta-thalassemia major by multislice multiecho T2*.
Objectives: Oral deferiprone (L1) appears to be promising in the treatment of beta-thalassemia major (TM) patients. T2* magnetic resonance imaging (MRI) with a single measurement in the mid-ventricular septum was validated as a quantitative evaluation of myocardial iron overload. Previous studies suggested a marked heterogeneity of iron distribution in the myocardium. We set up a multislice multiecho T2* MRI for the detection of this heterogeneity. The aim of our study was to investigate differences between the L1 vs. the subcutaneous desferrioxamine (DF)-treated patients using this new approach.Methods: Thirty-six beta-TM patients (age 29 +/- 8 yr) underwent MRI. Eighteen patients received…
Deferasirox, deferiprone and desferrioxamine treatment in thalassemia major patients: cardiac iron and function comparison determined by quantitative magnetic resonance imaging
Background Oral deferiprone was suggested to be more effective than subcutaneous desferrioxamine for removing heart iron. Oral once-daily chelator deferasirox has recently been made commercially available but its long-term efficacy on cardiac iron and function has not yet been established. Our study aimed to compare the effectiveness of deferasirox, deferiprone and desferrioxamine on myocardial and liver iron concentrations and bi-ventricular function in thalassemia major patients by means of quantitative magnetic resonance imaging. Design and Methods From the first 550 thalassemia subjects enrolled in the Myocardial Iron Overload in Thalassemia network, we retrospectively selected thalasse…
Myocardial fibrosis by delayed enhancement cardiovascular magnetic resonance and HCV infection in thalassemia major patients
ss Open Acce Oral presentation Myocardial fibrosis by delayed enhancement cardiovascular magnetic resonance and HCV infection in thalassemia major patients Alessia Pepe1, Antonella Meloni1, Zelia Borsellino2, Maria Chiara Dell'Amico1, Vincenzo Positano1, Caterina Borgna-Pignatti3, Aurelio Maggio4, Gennaro Restaino5, Francesco Gagliardotto2, Paolo Cianciulli6, Luciano Prossomariti7, Aldo Filosa7, Michele Centra8, Domenico D'Ascola9, Antonella Quarta10, Angelo Peluso11, Antonello Pietrangelo12, Eliana Cracolici13, Massimo Lombardi*1 and Marcello Capra2
Multislice multiecho T2* cardiac magnetic resonance for the detection of heterogeneous myocardial iron distribution in thalassaemia patients
The present study investigated myocardial T2* heterogeneity in thalassaemia major (TM) patients by cardiac magnetic resonance (CMR), to determine whether is related to inhomogeneous iron overload distribution. A total of 230 TM patients consecutively referred to our laboratory were studied retrospectively. Three short-axis views (basal, medium and apical) of the left ventricle (LV) were obtained by multislice multiecho T2* CMR. T2* segmental distribution was mapped on a 16-segment LV model. The level of heterogeneity of the T2* segmental distribution, evaluated by the coefficient of variation (CoV), was compared with that of a surrogate data set, to determine whether the inhomogeneous segme…
Single region of interest versus multislice T2* MRI approach for the quantification of hepatic iron overload.
Purpose To evaluate the effectiveness of the single ROI approach for the detection of hepatic iron burden in thalassemia major (TM) patients in respect to a whole liver measurement. Materials and Methods Five transverse hepatic slices were acquired by a T2* gradient-echo sequence in 101 TM patients and 20 healthy subjects. The T2* value was calculated in a single region of interest (ROI) defined in the medium-hepatic slice. Moreover, the T2* value was extracted on each of the eight ROIs defined in the functionally independent segments. The mean hepatic T2* value was calculated. Results For patients, the mean T2* values over segments VII and VIII were significantly lower. This pattern was su…
A T2* MRI Prospective Survey on Heart and Liver Iron In Thalassemia Major Patients Treated with Deferasirox Versus Deferiprone and Desferrioxamine In Monotherapy.
Abstract Abstract 4267 Introduction: Most deaths in thalassemia major (TM) result from cardiac complications due to iron overload. In thalassaemia available three iron chelation regimes in monotherapy may achieve different changes in cardiac iron and function and liver iron. No data are available in literature about prospective comparisons on cardiac iron and function and liver iron in TM patients treated with deferasirox (DFX) versus deferiprone (DFP) and desferrioxamine (DFO) in monotherapy. Magnetic Resonance (MR) is the unique non invasive suitable technique to evaluated quantitatively this issue. The aim of this multi-centre study was to assess prospectively in the clinical practice th…
Multislice multiecho T2* cardiovascular magnetic resonance for detection of the heterogeneous distribution of myocardial iron overload.
Purpose To assess the tissue iron concentration of the left ventricle (LV) using a multislice, multiecho T2* MR technique and a segmental analysis. Materials and Methods T2* multiecho MRI was performed in 53 thalassemia major patients. Three short-axis views of the LV were obtained and analyzed with custom-written software. The myocardium was automatically segmented into 12 segments. The T2* value on each segment as well as the global T2* value were calculated. Cine dynamic images were also obtained to evaluate biventricular function parameters by quantitative analysis. Results For the T2* global value, the coefficient of variation (CoV) for intra-/interobserver and interstudy reproducibili…
Nitrate-induced coronary vasodilation by stress-magnetic resonance imaging: A novel noninvasive test of coronary vasomotion
Purpose To evaluate the feasibility of assessing coronary vasodilation following exogenous nitrates, using magnetic resonance angiography (MRA). The assessment of coronary response to exogenous nitrovasodilators may have a diagnostic and prognostic impact in patients with coronary artery disease. To date, stress imaging of coronary artery vasomotion has been confined to the catheterization laboratory. MRA is emerging as a noninvasive tool for coronary artery imaging. Materials and Methods Coronary MRA was performed in 20 healthy volunteers (12 males, age = 33 ± 8). We used spiral spoiled gradient echo (SSGE) sequences for imaging of coronary artery lumen. After the baseline short-axis view …
Standardized T2* map of normal human heart in vivo to correct T2* segmental artefacts.
A segmental, multislice, multi-echo T2* MRI approach could be useful in heart iron-overloaded patients to account for heterogeneous iron distribution, demonstrated by histological studies. However, segmental T2* assessment in heart can be affected by the presence of geometrical and susceptibility artefacts, which can act on different segments in different ways. The aim of this study was to assess T2* value distribution in the left ventricle and to develop a correction procedure to compensate for artefactual variations in segmental analysis. MRI was performed in four groups of 22 subjects each: healthy subjects (I), controls (II) (thalassemia intermedia patients without iron overload), thala…
Influence of myocardial fibrosis and blood oxygenation on heart T2* values in thalassemia patients
Purpose To determine whether T2* measurements quantifying myocardial iron overload in thalassemia patients are influenced by myocardial fibrosis and blood oxygenation. Materials and Methods Multislice multiecho T2* was performed in 94 thalassemia patients in order to quantify myocardial iron overload. The left ventricle was automatically segmented into a 16-segment standardized heart model, and the T2* value on each segment as well as the global T2* were calculated. Delayed enhanced cardiovascular magnetic resonance (DE-CMR) images were obtained to detect myocardial fibrosis. The blood oxygenation was assessed by the noninvasive measurement of partial pressure of oxygen (pO2). Results Myoca…
Myocardial scarring by delayed enhancement cardiovascular magnetic resonance in thalassaemia major
Background: Cardiovascular magnetic resonance (CMR) by delayed enhancement (DE) enables visualisation of myocardial scarring, but no dedicated studies are available in thalassaemia major. Objective: To investigate the prevalence, extent, clinical and instrumental correlates of myocardial fibrosis or necrosis by DE CMR in patients with thalassaemia major. Patients: 115 Patients with thalassaemia major consecutively examined at an MRI laboratory. Methods: DE images were acquired to quantify myocardial scarring. Myocardial iron overload was determined by multislice multiecho T2*. Cine images were obtained to evaluate biventricular function. Results: DE areas were present in 28/115 patients (24…