الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 320 |  |  |
| | | from | 320 | | |
Abstract
C
hildren diagnosed with T1DM have a high risk of early subclinical and clinical CVD. Although intervention data are lacking, the American heart association categorizes children with type 1 diabetes in the highest tier for cardiovascular risk.
Myocardial damage in children may be clinically occult in a variety of stressful settings. Nevertheless, biochemical markers have not been routinely used in children at risk for myocardial damage due to a lack of sufficient specificity to unambiguously guide patient management.
Speckle Tracking Echocardiography helps in assessment of cardiac mechanics in the three spatial planes: longitudinal, circumferential, and radial. Hence, enabling early detection of changes in heart performance and, as a consequence, promoting more effective therapeutic approaches. Longitudinal strain seems to be the earliest to be affected by ischemia, as the subendocardial fibres are the first to suffer the effects of perfusion abnormalities.
Hemodynamic monitoring is the cornerstone of critical care. One of the primary goals of hemodynamic monitoring is to alert the physician to impending cardiovascular crisis before organ or tissue injury ensues.
Children with T1DM presenting with DKA are at risk but rarely screened for myocardial injury. Frequency of such injury among this population is unknown.
The aim of this cross-sectional case-control study was to assess the hemodynamic status and cardiac functions in children with T1DM presenting with DKA, investigate the possibility of occurrence of myocardial injury, predict the possible risk factors for hypothesized myocardial injury and explore the difference between children with new-onset DKA and those with recurrent DKA as regard the studied parameters.
Any child that met the eligibility criteria and aged 3 to 18 years from both sexes presenting with moderate or severe DKA and those sex- and age-matched controls were included in the study.
Patients who had (any structural heart disease, hypertension, anemia, type 2 diabetes mellitus, hyperosmolar hyperglycemic state, mild DKA, other chronic diseases, acute renal insufficiency), patients on any regular medications except for insulin, children with BMI ≥ 85th percentile for age, DKA patients whom missed follow up due to death, discharge and/or refusal of follow up, those with echocardiographic studies having missing or poor quality images as well as those having lipemic or hemolysed samples were excluded.
Forty children presenting with DKA (20 child with new-onset DKA and 20 child with recurrent DKA), were recruited from the emergency department, at Children’s hospital, Ain Shams university. The patients group was compared to twenty age- and sex-matched controls. Each child was fully assessed by having complete history, full clinical examination, 12-lead ECG as well as two echocardiographic studies (a base-line and 72 hours follow-up) with TDI and 2D speckle tracking echocardiography. Biochemical evidence of myocardial injury was assessed at presentation and after recovery using multi-marker strategy utilizing cTnI, H-FABP and myoglobin. Complete blood picture, lipid profile and full metabolic profile were also performed to patients at presentation.
The obtained data was then collected, tabulated and statistically analyzed.
The study found that weight, height, BMI and BMI percentile for age were significantly lower in the patients group when compared to controls.
Although there was insignificant statistical difference between patients and controls as regard age or gender, patients had significantly lower body surface area when compared to controls which in turn necessitated the use of z-score as a reference for different cardiac structures and mitral valve tissue velocities as well as usage of blood pressure percentiles for age.
The present study found blood pressure percentiles for age and sex were higher in the patient group when compared to controls in spite of the former being moderately dehydrated.
The study of left ventricular walls dimensions disclosed a tendency to ventricular hypertrophy among recurrent DKA compared to the newly diagnosed with 22.5% having established LVH by definition all of them having recurrent DKA.
Echocardiographic hemodynamic assessment upon presentation revealed significantly lower IVC maximal diameter of the patients compared to control, yet, IVCCI didn’t differ. The study showed also pre-treatment lower LVOT stroke volume flow, LVOT to SVC flow ratio of patients in relation to control which could be explained by hypovolemia together with the lower EF.
Utilizing the mitral inflow velocity, DKA patients had abnormal diastolic function of the left ventricle which improved after resolution of DKA with decreased peak E velocity, increased peak A velocity and decreased E/A ratio. Upon using TDI indices, there were significantly lower tissue Doppler e’ velocities and lateral annular e’ z-score together with higher Tei index among DKA patients compared to control.
Using the load independent E/E’ ratio to assess diastolic function, the study found that the ratio was higher among diabetics compared to control, however, it decreased to reach normalization after treatment in newly diagnosed DKA cases which indicates the reversibility of this insult after recovery from DKA and rehydration.
On the other hand, in recurrent DKA, the E/E’ ratio tends to increase after treatment with more worse diastolic function which ensues elevated filling pressure secondary to possible relaxation abnormality.
Analysis of speckle tracking derived strain in the present study revealed that; although overall GLPS values didn’t reach values of impaired GLPS, yet there was significant reduction of GLPS among patients when compared to controls which was more significant while being on DKA with 40% of patients do have impaired GLPS. Moreover, the overall GLPS was impaired in those with established T1DM presenting with DKA, while new onset DKA had normal overall GLPS even during DKA. Fortunately, overall GLPS of both groups increased after resolution of DKA.
The present study used multi-marker approach for detection of myocardial injury, it revealed significantly increased cTnI, H-FABP and myoglobin levels compared to controls. Adding the ECG evidence of ischemia (i.e. normal potassium level with decreased QRS duration and normal to prolonged cQT interval), suggested the proposed myocardial ischemia. Unfortunately, 25% of the studied children with DKA at presentation had elevated cTnI levels consistent with active myocardial injury.
A strong positive correlation between cTnI level and diabetes duration, number of previous DKA episodes, cQT duration, TG, LDL, Tei index and the average GLPS in the current study.
Higher diastolic blood pressure percentiles and serum LDL were the only independent predictors of elevated cTnI in a stepwise regression model.