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.

The relationships between pancreatic T2* values and pancreatic iron loading with cardiac dysfunctions, hepatic and cardiac iron siderosis among Egyptian children and young adults with ß-thalassaemia major and sickle cell disease: a cross-sectional study.

Background: Cardiac, hepatic and pancreatic T2* measured by magnetic resonance imaging (MRI) has been proven to be an accurate and non-invasive method for measuring iron overload in iron overload conditions. There is accumulating evidence that pancreatic iron can predict cardiac iron in young children because the pancreas loads earlier than the heart. The aim of our study was to investigate cardiac function and cardiac iron and their relation to pancreatic iron among patients with ß-thalassaemia major (ßTM) and sickle cell disease (SCD). Methods: 40 ßTM and 20 transfusion-dependant SCD patients were included along with 60 healthy age-matched controls. Echocardiography and Tissue Doppler Imaging were performed for all subjects as well as the control group.  Hepatic, cardiac and pancreatic iron overload in cases were assessed by MRI T2*. Results: The study group consisted of 40 ßTM and 20 transfusion dependant SCD patients with mean age 13.7 years and mean frequency of transfusion/year 12. Mean cardiac T2* was 32.9 ms and mean myocardial iron concentration was 0.7 mg/g; One patient had cardiac iron overload of moderate severity. Mean pancreatic T2* was 22.3 ms with 20 patients having mild pancreatic iron overload. Pancreatic T2* correlated positively with main pulmonary artery diameter (p=0.046), peak late diastolic velocity at septal mitral annulus (p=0.038), peak early diastolic velocity at tricuspid annulus (p=0.001) and mitral annular plane systolic excursion (p=0.01); and negatively with end systolic pulmonary artery pressure (p=0.007). We couldn't test the predictability of pancreatic T2* in relation to cardiac T2* as only one patient had cardiac T2*<20 ms. Conclusion: Assessment of pancreatic T2* in multi-transfused patients with ßTM and SCD can predict myocardial dysfunction. No direct relation between pancreatic iron and cardiac siderosis was detected.

Prevalence of myocarditis in pediatric intensive care unit cases presenting with other system involvement / Prevalência de miocardite em casos pediátricos na unidade de terapia intensiva, com envolvimento de outros sistemas

OBJECTIVE: To assess children with myocarditis, the frequency of various presenting symptoms, and the accuracy of different investigations in the diagnosis. METHODS: This was an observational study of 63 patients admitted to PICU with non-cardiac diagnosis. Cardiac enzymes, chest-X ray, echocardiography, and electrocardiogram were performed to diagnose myocarditis among those patients. RESULTS: There were 16 cases of definite myocarditis. The age distribution was non-normal, with median of 5.5 months (3.25-21). Of the 16 patients who were diagnosed with myocarditis, 62.5% were originally diagnosed as having respiratory problems, and there were more females than males. Among the present cases, the accuracy of cardiac enzymes (cardiac troponin T [cTn] and creatine phosphokinase MB [CKMB]) in the diagnosis of myocarditis was only 63.5%, while the accuracy of low fractional shortening and of chest-X ray cardiomegaly was 85.7 and 80.9%; respectively. Cardiac troponin folds 2.02 had positive predictive value of 100%, negative predictive value of 88.7%, specificity of 100%, sensitivity of 62.5%, and accuracy of 90.5%. CONCLUSIONS: Children with myocarditis present with symptoms that can be mistaken for other types of illnesses. When clinical suspicion of myocarditis exists, chest-X ray and echocardiography are sufficient as screening tests. Cardiac troponins confirm the diagnosis in screened cases, with specificity of 100%. .

OBJETIVO: Determinar as crianças com miocardite, a frequência de sintomas apresentados e a precisão de investigações no diagnóstico. MÉTODOS: Estudo observacional de 63 pacientes internados na UTIP com diagnóstico de problemas não cardíacos. Os exames de enzimas cardíacas, raios-X do tórax, ecocardiograma e eletrocardiograma (ECG) foram feitos para diagnosticar miocardite entre os pacientes. RESULTADOS: Houve 16 casos de miocardite definida. A distribuição etária não foi normal, com média de 5,5 meses (3,25-21). Dos 16 pacientes, 62,5% foram originalmente diagnosticados com problemas respiratórios e a mulheres estavam em maior número do que os homens. Dentre nossos casos, a precisão das enzimas cardíacas (cTn e CKMB) no diagnóstico da miocardite foi de apenas 63,5%, apesar de a precisão da baixa fração de encurtamento (FS) e dos raios-X de tórax que revelaram cardiomegalia ter sido 85,7% e 80,9%; respectivamente. A troponina cardíaca em 2,02 vezes apresentou valor preditivo positivo = 100%, valor preditivo negativo = 88,7%, especificidade = 100%, sensibilidade = 62,5% e precisão = 90,5%. CONCLUSÕES: As crianças com miocardite apresentam sintomas que podem ser confundidos com outros tipos de doenças. Quando há suspeita clínica de miocardite, raios-X de tórax e ecocardiografia são testes de rastreamento suficientes. As troponinas cardíacas confirmam o diagnóstico em casos examinados, com especificidade de 100%. .

The effect of on-line hemodiafiltration on improving the cardiovascular function parameters in children on regular dialysis.

The cardiovascular disease is an important cause of morbidity and accounts for almost 50% of deaths in patients undergoing maintenance dialysis. Many harmful molecules of the uremic milieu, such as the middle molecules, are difficult to remove by conventional hemodialysis (HD). On-line hemodiafiltration (OL-HDF) can achieve a considerable clearance of middle molecules and, together with its sterile ultrapure infusate, may have favorable effects on inflammation and cardiovascular complications. We aimed in this study to assess the effect of OL-HDF on improving the chronic inflammatory state associated with chronic kidney disease and the possible impact of these changes on myocardial function in chronic HD children. Thirty pediatric patients [12 (40%) males and 18 (60%) females with a mean age of 11.3 ± 3.2 years] on conventional HD for at least six months were switched to OL-HDF for six months. Variables for comparison at the end of each period included the levels of serum C-reactive protein and Kt/V as well as electrocardiography and echocardiographic measurements, including left ventricular mass index (LVMI). On changing from HD to OL-HDF, there was a significant decrease in hs-CRP (from 7.9 ± 8.9 to 3.4 ± 3 µ g/mL) (P = 0.01) and frequency of diastolic dysfunction (P = 0.04), while systolic function (FS and EF) improved significantly (P = 0.007 and 0.05, respectively), while LVMI did not change. We conclude that OL-HDF was well tolerated in children with improvement of the systolic function of the myocardium and the overall frequency of diastolic dysfunction.

Prevalence of myocarditis in pediatric intensive care unit cases presenting with other system involvement.

OBJECTIVE: To assess children with myocarditis, the frequency of various presenting symptoms, and the accuracy of different investigations in the diagnosis. METHODS: This was an observational study of 63 patients admitted to PICU with non-cardiac diagnosis. Cardiac enzymes, chest-X ray, echocardiography, and electrocardiogram were performed to diagnose myocarditis among those patients. RESULTS: There were 16 cases of definite myocarditis. The age distribution was non-normal, with median of 5.5 months (3.25-21). Of the 16 patients who were diagnosed with myocarditis, 62.5% were originally diagnosed as having respiratory problems, and there were more females than males. Among the present cases, the accuracy of cardiac enzymes (cardiac troponin T [cTn] and creatine phosphokinase MB [CKMB]) in the diagnosis of myocarditis was only 63.5%, while the accuracy of low fractional shortening and of chest-X ray cardiomegaly was 85.7 and 80.9%; respectively. Cardiac troponin folds 2.02 had positive predictive value of 100%, negative predictive value of 88.7%, specificity of 100%, sensitivity of 62.5%, and accuracy of 90.5%. CONCLUSIONS: Children with myocarditis present with symptoms that can be mistaken for other types of illnesses. When clinical suspicion of myocarditis exists, chest-X ray and echocardiography are sufficient as screening tests. Cardiac troponins confirm the diagnosis in screened cases, with specificity of 100%.