Evaluation of cardiac autonomic dysfunctions in children with type 1 diabetes mellitus.

BACKGROUND: Cardiovascular autonomic neuropathy (CAN) is a serious complication of diabetes, impacting the autonomic nerves that regulate the heart and blood vessels. Timely recognition and treatment of CAN are crucial in averting the onset of cardiovascular complications. Both clinically apparent autonomic neuropathy and subclinical autonomic neuropathy, particularly CAN pose a significant risk of morbidity and mortality in children with type 1 diabetes mellitus (T1DM). Notably, CAN can progress silently before manifesting clinically. In our study, we assessed patients with poor metabolic control, without symptoms, following the ISPAD 2022 guideline. The objective is is to determine which parameters we can use to diagnose CAN in the subclinical period. METHODS: Our study is a cross-sectional case-control study that includes 30 children diagnosed with T1DM exhibiting poor metabolic control (average HbA1c > 8.5% for at least 1 year) according to the ISPAD 2022 Consensus Guide. These patients, who are under the care of the pediatric diabetes clinic, underwent evaluation through four noninvasive autonomic tests: echocardiography, 24-h Holter ECG for heart rate variability (HRV), cardiopulmonary exercise test, and tilt table test. RESULTS: The average age of the patients was 13.73 ± 1.96 years, the average diabetes duration was 8 ± 3.66 years, and the 1-year average HbA1c value was 11.34 ± 21%. In our asymptomatic and poorly metabolically controlled patient group, we found a decrease in HRV values, the presence of postural hypotension with the tilt table test, and a decrease in ventricular diastolic functions that are consistent with the presence of CAN. Despite CAN, the systolic functions of the ventricles were preserved, and the dimensions of the cardiac chambers and cardiopulmonary exercise test were normal. CONCLUSIONS: CAN is a common complication of T1DM, often associated with the patient's age and poor glycemic control. HRV, active orthostatic tests, and the evaluation of diastolic dysfunctions play significant roles in the comprehensive assessment of CAN. These diagnostic measures are valuable tools in identifying autonomic dysfunction at an early stage, allowing for timely intervention and management to mitigate the impact of cardiovascular complications associated with T1DM.

Prognostic Value of Tpeak-Tend Interval in Early Diagnosis of Duchenne Muscular Dystrophy Cardiomyopathy.

The most common cause of death in patients with Duchenne muscular dystrophy (DMD) is cardiomyopathy. Our aim was to investigate the relationship between the Tpeak-Tend (Tp-e) interval and the premature ventricular contraction (PVC) burden and therefore early arrhythmic risk and cardiac involvement in DMD patients. Twenty-five patients with DMD followed by pediatric cardiology were included in the study. Those with a frequency of <1% PVC in the 24 h Holter were assigned to Group 1 (n = 15), and those with >1% were assigned to Group 2 (n = 10). Comparisons were made with healthy controls (n = 27). Left ventricular ejection fraction (LVEF) was lowest in Group 2 and highest in the control group (p < 0.001). LV end-diastolic diameter was greater in Group 2 than in Group 1 and the control group (p = 0.005). Pro-BNP and troponin levels were higher in Group 1 and Group 2 than in the control group (p = 0.001 and p < 0.001, respectively). Tp-e interval was longer in Group 2 compared to Group 1 and the control group (p < 0.001). The LVEF (OR 0.879, 95% CI 0.812-0.953; p = 0.002) and Tp-e interval (OR 1.181, 95% CI 1.047-1.332; p = 0.007) were independent predictors of PVC/24 h frequency of >1%. A Tp-e interval > 71.65 ms predicts PVC > 1%, with a sensitivity of 80% and a specificity of 90% (AUC = 0.842, 95% CI (0.663-1.000), p = 0.001). Determination of Tp-e prolongation from ECG data may help in the determination of cardiac involvement and early diagnosis of arrhythmic risk in DMD.

Subclinical myocardial assessment after BNT162b2 messenger RNA COVID-19 vaccination in adolescents with chronic heart disease: a speckle-tracking echocardiography study.

PURPOSE: Case reports of the development of perimyocarditis in adolescents and young adults after BNT162b2 messenger RNA (mRNA) COVID-19 vaccination have raised concerns about the cardiac side effects of the vaccine. The aim of the study was to evaluate clinical follow-up and subclinical myocardial function after mRNA COVID-19 vaccine in adolescents with chronic heart disease. METHODS: Forty-one adolescents aged 12-18 who were followed up at paediatric cardiology clinic between December 2021 and May 2022, and who had received two doses of the Pfizer-BioNTech COVID-19 mRNA vaccine were included in the study. The patients were evaluated five times in total - before the vaccination, one week after receiving the first dose, one month after receiving the first dose, one week after receiving the second dose, and one month after receiving the second dose. Cardiac assessment for all patients included an electrocardiogram, transthoracic echocardiography, and two-dimensional speckle-tracking strain echocardiography for left ventricular subclinical myocardial function. RESULTS: The mean age of the adolescents was 16.2 ± 1.5 years, and 56% (n = 23) were male. There was no statistically significant difference in patients' echocardiographic measurements including left ventricular global longitudinal strain and electrocardiogram parameters including PR, QRS, and QTc intervals through the follow-up. Seven patients reported cardiac complaints at post-vaccination follow-up visits, but laboratory and echocardiographic evidence of cardiac involvement was not observed. CONCLUSIONS: Based on the results of our study, the mRNA COVID-19 vaccine did not cause impairment in subclinical myocardial function assessed by speckle-tracking echocardiography in adolescents with chronic heart disease.

The relation of echo-derived lateral MAPSE to left heart functions and biochemical markers in patients with preserved ejection fraction: Short-term prognostic implications.

OBJECTIVE: Mitral annular plane systolic excursion (MAPSE) is a simple way to evaluate-left ventricle (LV) function. Our aim was to explain the relationship of MAPSE with LV function and biochemical markers in patients with preserved ejection fraction (EF), and to determine whether it has an effect on prognosis in echocardiography (echo) practice. METHODS: Consecutive patients referred to the echo laboratory between November 2020 and March 2021 were included in the study. In addition to conventional parameters, MAPSE of the lateral mitral annulus was measured in all patients. Patients were divided into three groups according to lateral MAPSE: low (<12 mm), relatively preserved (12-15 mm), and high (≥15 mm). RESULTS: A total of 512 patients with preserved EF were included in the study. MAPSE was low in 44 patients (9%), relatively preserved in 231 patients (45%), and high in 237 patients (46%). The mean age was higher in the low group compared to the other two groups (p < 0.001) and the body mass index was increased in the low group compared to the high group (p = 0.010). Atrial fibrillation and hypertension were more common in patients with low MAPSE. The rate of diastolic dysfunction (DD) and all-cause hospitalization were higher in the low and relatively preserved groups than in the high group (p < 0.001, p = 0.002; respectively). The pro-BNP level and mortality rate were higher in the low group compared to the relatively preserved and high groups (p = 0.007, p = 0.005; respectively). MAPSE was identified as independent predictor of hospitalization (OR: 0.284, 95% CI: 0.093-0.862, p = 0.026) via multivariate analysis and independent predictor of in-hospital mortality (HR: 0.002, 95% CI: 0-0.207, p = 0.008). CONCLUSIONS: Analysis of LV longitudinal function by echo-derived lateral MAPSE when LV ejection fraction is normal provides important information about DD and related heart failure and may predict prognosis in echo practice.