Can myocardial remodeling be a useful surrogate predictor of myocardial iron load? A 3D echocardiographic multicentric study.

The relationship between myocardial iron load and eccentric myocardial remodeling remains an under-investigated area; it was thought that remodeling is rather linked to fibrosis. This study aims to determine whether or not measures of remodeling can be used as predictors of myocardial iron. For this purpose, 60 patients with thalassemia were studied with 3D echocardiography and myocardial relaxometry (T2*) by Cardiac MRI. 3D derived sphericity index was significantly higher in patients with myocardial iron load. It was correlated with T2* with a 100% sensitivity and specificity (cut-off value of 0.34) to discriminate between patients with and without myocardial iron overload.

Delayed Myocardial Enhancement in Pediatric Hypertrophic Cardiomyopathy: Correlation with LV Function, Echocardiography, and Demographic Parameters.

Our aim was (1) to detect the presence of fibrosis by Cardiac magnetic resonance imaging (CMR) in the pediatric age group. (2) Correlate CMR findings with demographic data, LV function, and other echocardiographic parameters. We studied 40 pediatric patients diagnosed as HCM by echocardiography. All patients were subjected to clinical examination (in which the NYHA classification was determined for each patient), echocardiography, and CMR. CMR was done on a 1.5T Philips Achieva scanner in SSFP with delayed myocardial enhancement (DE-MRI). All demographic and functional parameters as well as pressure gradient across left ventricular outflow tract (LVOT) were correlated with the percentage of myocardial enhancement. We studied 13 female and 27 male patients from 45 days up to 18 years. The mean percentage of DE-MRI was 9.7 ± 9%. We found significant correlation between the NYHA classification and the pressure gradient across the LVOT (P = < 0.001) as well as the percentage of DE-MRI (P = 0.004). The percentage of DE-MRI showed positive correlation with LV myocardial mass index (P = 0.042). It didn't correlate with any other demographic or LV functional cardiac parameters. A good positive correlation was detected between the percentage of DE-MRI and the severity of pressure gradient across LVOT measured by echocardiography (r = 0.69 and P = <0.001). We found a significant correlation between the percentage of DE-MRI in children with HCM and the pressure gradient across LVOT, NYHA classification, and LV myocardial mass. This may help in the further management of those patients, planning for follow-up, and prognosis of the disease.

Hypertrophic cardiomyopathy: prognostic factors and survival analysis in 128 Egyptian patients.

BACKGROUND: Hypertrophic cardiomyopathy is an important cause of disability and death in patients of all ages. Egyptian children may differ from Western and Asian patients in the pattern of hypertrophy distribution, clinical manifestations, and risk factors. OBJECTIVES: The aim of our study was to report the clinical characteristics and outcomes of Egyptian children with hypertrophic cardiomyopathy studied over a 7-year duration and to determine whether the reported adult risk factors for sudden cardiac death are predictive of the outcome in these affected children. STUDY DESIGN AND METHODS: This retrospective study included 128 hypertrophic cardiomyopathy children. The data included personal history, family history, physical examination, baseline laboratory measurements, electrocardiogram, and Holter and echocardiographic results. Logistic regression analysis was used for the detection of risk factors of death. RESULTS: Fifty-one out of 128 patients died during the period of the study. Of the 51 deaths, 36 (70.5%) occurred in patients presenting before 1 year of age. Only eight patients had surgical intervention. Extreme left ventricular hypertrophy, that is, interventricular septal wall thickness or posterior wall thickness Z-score >6, sinus tachycardia, and supraventricular tachycardia were found to be independent risk factors for prediction of death in patients with hypertrophic cardiomyopathy. CONCLUSIONS: At our Egyptian tertiary care centre, hypertrophic cardiomyopathy has a relatively worse prognosis when compared with reports from Western and Asian series. Infants have a worse outcome than children presenting after the age of 1 year. A poorer prognosis in childhood hypertrophic cardiomyopathy is predicted by an extreme left ventricular hypertrophy, the presence of sinus tachycardia, and supraventricular tachycardia.

Deferoxamine-induced dysplasia-like skeletal abnormalities at radiography and MRI.

BACKGROUND: Current thalassemia major treatment includes blood transfusion and iron chelation, which is associated with growth disturbances and radiographic changes in the long bone metaphyses. OBJECTIVE: To explore and discuss the spectrum of deferoxamine-induced bone-dysplasia-like changes in children with thalassemia major in Egypt. MATERIALS AND METHODS: We studied 59 Egyptian children with thalassemia major and generalized arthralgia. All started deferoxamine treatment at 3 years of age. We conducted skeletal survey and MRI of both knees in radiographically positive children. Each child's age, serum ferritin, age of onset and duration of therapy were compared with the radiologic findings. RESULTS: Twenty-two (37.3%) children had variable degrees of skeletal dysplasia-like changes similar to those described with deferoxamine intake, mostly around the knees. Mild dysplasia-like changes were seen in 4 (18%) children; moderate changes were seen in 11 (50%) children and severe changes were seen in 7 (31.8%) children. No statistically significant relationships were detected between bone changes and the children's age, age of starting deferoxamine, duration of therapy, or serum ferritin level. CONCLUSION: A wider spectrum of deferoxamine-induced bone-dysplasia-like changes was recognized despite delayed onset and small doses of therapy. These changes should be considered as a possible cause of arthropathy in children with thalassemia major, especially symptomatic children.

Cardiac autonomic neuropathy linked to left ventricular dysfunction in type 1 diabetic patients.

Type 1 diabetes is a major cause of cardiovascular death; diabetic cardiomyopathy (DCM) is the most important cause of mortality among diabetic patients. There is an increasing body of evidence that the most important inducer of DCM is microvascular injury. The aim of this study is to establish a potential relationship between low frequency/high frequency (LF/HF) ratio and DCM and to set a possible predictive cutoff of LF:HF ratio for early detection of DCM. Methods: 75 type 1 diabetic patients together with 75 controls were assessed using tissue Doppler imaging for left ventricular (LV) and right ventricular (RV) diastolic function, and heart rate variability (HRV) indices including LF/HF ratio. Type 1 diabetic patients were also assessed for parameters of glycemic and lipid profile control. Results: Cases showed a statistically significant increase in LF/HF ratio compared to controls reflecting reduced HRV. Also, LV and RV diastolic function were reduced in cases compared to controls, there was a significant correlation between LV E/E' ratio (ratio of early transmitral velocity and average early mitral annular and basal septal velocities) and LF/HF ratio. LF/HF ratio was able to predict LV diastolic dysfunction as expressed by the LV E/E' ratio with a sensitivity of 96%. Conclusion: HRV indices notably LF/HF ratio seem to be an early and sensitive predictor of DCM, the latter finding not only underlines the role of microvascular injury in the induction of DCM but might help also for the early detection and reversal of it.

Revisiting the pathogenic role of insulin resistance in Duchenne muscular dystrophy cardiomyopathy subphenotypes.

INTRODUCTION: Duchenne muscular dystrophy (DMD) is known to impact the subepicardial layer of the myocardium through chronic inflammation. Recent animal studies have shown predominant subendocardial involvement in rats with DMD. The primary outcome parameter was to determine by cardiovascular MRI (CMR) if two differential patterns of myocardial involvements exist in DMD; the secondary outcome parameters were to correlate the observed pattern with metabolic markers such as insulin resistance measures. METHODS: Forty patients with DMD were screened using CMR to determine which of them had predominantly subendocardial dysfunction (SENDO group), or subepicardial/midmyocardial involvement (SEPMI group). Patients were subjected to body mass index measurement, serum creatinine kinase, serum lactate dehydrogenase enzyme, fasting glucose-insulin ratio (FGIR), full lipid profile, left ventricular ejection fraction (LVEF), left ventricle E/E´ ratio (the ratio of early mitral inflow velocity to average early diastolic velocities of the basal septum and mitral annulus) for left ventricle diastolic function, and myocardial layer strain discriminating echocardiography (MLSD-STE). Results: 26 patients displayed SENDO while 34 displayed SEPMI. SENDO group displayed overt insulin resistance; (FGIR (SENDO: 7 ± 1 vs. SEPMI: 5 ± 1, P < 0.001). FGIR was negatively correlated with Subendocardial Global Longitudinal Strain (ENDO-LS) with r = -0.75. CONCLUSION: DMD does not seem to influence the heart uniformly; DMD cardiomyopathy probably has two separate phenotypes with different mechanisms. Insulin resistance might be implicated in its pathogenesis and its reversal may help to slow disease progression.