ABSTRACT
Thalassemia major (TM) patients have altered ventricular volumes and ejection fraction compared to normals, although evidence for these findings stem from restricted patient groups and has never been reproduced. We sought to evaluate cardiac parameters by cardiovascular magnetic resonance (CMR) in a group of young TM patients not covered by previous studies that are more representative of the TM population in many countries. Seventy patients including 40 TM with normal myocardial iron concentrations, and 30 age- and gender-matched normal (NL) volunteers underwent a CMR study for assessment of left and right ventricle volumes and function using a 1.5-T scanner. Left and right ventricle ejection fraction, indexed systolic and diastolic volumes, and indexed mass were compared between the two groups. Mean age of TM patients was 18.2 ± 7.1 versus 17.5 ± 8.5 years in NL with no significant differences (P = 0.73). There was no difference in left ventricular (LV) ejection fraction between the groups (TM 64.9 ± 5.7 %, NL 64.9 ± 5.2 %; P = 0.97). LV normalized end-diastolic and end-systolic volumes were significantly higher in patients with TM compared to NL volunteers (76.8 ± 19.4 versus 66.6 ± 11.7 mL/m², P = 0.008, and 27.0 ± 8.8 versus 23.6 ± 5.0 mL/m², P = 0.045). LV indexed mass was also higher in TM patients compared to NL (51.2 ± 11.9 versus 42.0 ± 8.5 g/m², P < 0.001). No significant differences were observed in right ventricular parameters. In conclusion, younger patients with TM do not present different left or right ventricular function values compared to normal controls despite having increased left ventricular volumes and mass.
Subject(s)
Heart Ventricles/physiopathology , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Right/physiopathology , beta-Thalassemia/physiopathology , Adolescent , Adult , Brazil , Cardiac Volume , Child , Cohort Studies , Early Diagnosis , Female , Heart Ventricles/chemistry , Heart Ventricles/pathology , Humans , Iron/analysis , Magnetic Resonance Imaging , Male , Myocardium/chemistry , Myocardium/pathology , Severity of Illness Index , Sex Characteristics , Stroke Volume , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/etiology , Ventricular Dysfunction, Left/pathology , Ventricular Dysfunction, Right/diagnosis , Ventricular Dysfunction, Right/etiology , Ventricular Dysfunction, Right/pathology , Young AdultABSTRACT
OBJECTIVES: To assess the level of agreement and interchangeability among different software programs for calculation of T2 values for iron overload. METHODS: T2 images were analysed in 60 patients with thalassaemia major using the truncation method in three software programs. Levels of agreement were assessed using Pearson correlation and Bland-Altman plots. Categorical classification for levels of iron concentration by each software program was also compared. RESULTS: For the heart, all correlation coefficients were significant among the software programs (P < 0.001 for all coefficients). The mean differences and 95% limits of agreement were 0.2 (-4.73 to 5.0); 0.1 (-4.0 to 3.9); and -0.1 (-4.3 to 4.8). For the liver all correlations were also significant with P < 0.001. Bland-Altman plots showed differences of -0.02 (-0.7 to 0.6); 0.01 (-0.4 to 0.4); and -0.02 (-0.6 to 0.6). There were no significant differences in clinical classification among the software programs. CONCLUSIONS: All tools used in this study provided very good agreement among heart and liver T2 values. The results indicate that interpretation of T2 data is interchangeable with any of the software programs tested. KEY POINTS: Magnetic resonance imaging in iron overload assessment has become an essential tool. Post processing options to establish T2 values have not been compared. No differences were found on T2 of the liver or heart using 3 different techniques. Availability of these methods should allow more widespread interpretation of iron overload by MRI.
