Cardiac Autonomic Dysfunction Research Articles

Changes in blood metabolomes as potential markers for severity and prognosis in doxorubicin-induced cardiotoxicity: a study in HER2-positive and HER2-negative breast cancer patients.

We aimed to compare the changes in blood metabolomes and cardiac parameters following doxorubicin treatment in HER2-positive and HER2-negative breast cancer patients. Additionally, the potential roles of changes in blood metabolomes as severity and prognostic markers of doxorubicin-induced cardiotoxicity were determined. HER2-positive (n = 37) and HER2-negative (n = 37) breast cancer patients were enrolled. Cardiac function assessment and blood collection were performed at baseline and 2weeks after completion of doxorubicin treatment in all patients, as well as at three months after completion of doxorubicin treatment in HER2-negative breast cancer patients. Blood obtained at all three-time points was processed for measuring cardiac injury biomarkers. Blood obtained at baseline and 2weeks after completion of doxorubicin treatment were also processed for measuring systemic oxidative stress and 85 metabolome levels. Cardiac injury and systolic dysfunction 2weeks after completion of doxorubicin treatment were comparable between these two groups of patients. However, only HER2-negative breast cancer patients exhibited increased systemic oxidative stress and cardiac autonomic dysfunction at this time point. Moreover, 33 and 29 blood metabolomes were altered at 2weeks after completion of doxorubicin treatment in HER2-positive and HER2-negative breast cancer patients, respectively. The changes in most of these metabolomes were correlated with the changes in cardiac parameters, both at 2weeks and 3months after completion of doxorubicin treatment. The changes in blood metabolomes following doxorubicin treatment were dependent on HER2 status, and these changes might serve as severity and prognostic markers of doxorubicin-induced cardiotoxicity. The study was conducted under ethical approval from the Institutional Review Board of the Faculty of Medicine, Chiang Mai University (Registration number: MED-2563-07001; Date: April 28, 2020). The study also complied with the Declaration of Helsinki.

Complications during Adolescence Predict Mortality in Young Adults with Childhood Onset Type 1 Diabetes

Objective. Microvascular complications increase the risk of cardiovascular disease and premature death in adults with type 1 diabetes. We examined the association between microvascular complications during adolescence, including cardiac autonomic nerve dysfunction and subsequent mortality. Research Design and Methods. We undertook data linkage with the Australian National Death Index in a cohort of 409 adolescents (diagnosed between 1973 and 1993), 48% male, median age at final complications assessment 17.4 years (interquartile range: 16.0–18.9), followed longitudinally for median 22.3 years (21.0–23.4) from diagnosis. Generalized estimating equations (GEE) were used to examine associations between mortality and adolescent complications. Mortality risk was calculated as standardized mortality ratio (SMR). Results. At final adolescent visit, 20% had CAN abnormality, 30% abnormal pupillary response, 20% albuminuria, 40% early elevation of albumin excretion rate (AER) and 45% retinopathy. Data linkage 8–13 years later showed 14 were deceased (3% of cohort), 57% male, median age 28.3 years (24.8–32.9). Acute or chronic diabetes complications accounted for 25% of deaths. In multivariable GEE, elevated AER (OR 4.54, 1.23–16.80, p=0.030), pupillary abnormality (OR 4.27, 1.20–15.22, p=0.023), systolic blood pressure SDS (OR 2.17, 1.26–3.74, p=0.005) and CAN (OR 4.65, 1.03–21.0, p=0.045) predicted mortality. HbA1c was not significant. SMR was 2.5 (1.4–4.2) and was higher in females (SMR 3.5, 1.3–7.8) but not in males (SMR 2.1, 0.9–4.0). Conclusion. Mortality in young adults with type 1 diabetes is predicted by subclinical markers of autonomic neuropathy and elevated AER during adolescence, but not glycemia. Mortality was over twice that of the background population in females but not in males.

Cardiac Rhythm Aberrations in Subacute Sclerosing Panencephalitis: Insights From Heart Rate Variability Analysis.

Subacute sclerosing panencephalitis (SSPE) is a fatal neurological disorder resulting from persistent measles virus infection within the brain. Although neurological manifestations have been well-documented, the impact of SSPE on cardiac autonomic function, assessed through heart rate variability (HRV), remains understudied. In this prospective single-center study conducted from January 2022 to March 2023 in Southern India, 30 consecutive SSPE patients and age- and sex-matched controls underwent electrocardiogram recordings for HRV analysis. Various HRV parameters were assessed, including time-domain metrics (SD of normal-to-normal intervals, root mean square of successive differences between normal heartbeats, percentage of successive normal interbeat intervals greater than 50 msec), SD1 and SD2 for Poincaré plot analysis, and frequency-domain metrics (low frequency %, high frequency %, low frequency:high frequency ratio). In the study, SSPE patients exhibited markedly reduced HRV. Specifically, SD of normal-to-normal intervals (P = 0.003), percentage of successive normal interbeat intervals greater than 50 msec (P = 0.03), and SD2 (P = 0.0016) were significantly lower compared with controls. Frequency-domain analysis did not reveal significant distinctions. Correlation analysis demonstrated a negative relationship between percentage of successive normal interbeat intervals greater than 50 msec and SSPE severity (r = -0.37, P = 0.042). Heart rate variability did not significantly differ between SSPE stages or with clinical variables. The interbeat interval range showed a narrower distribution in SSPE subjects. Our study highlights the clinical relevance of HRV analysis in SSPE and autonomic dysfunction throughout the disease course underscoring its importance in SSPE. This investigation provides valuable insights into cardiac autonomic dysfunction probably because of affliction of the central autonomic networks caused by the disease process and may be a contributing factor to mortality in SSPE.

Cardiac autonomic dysfunction and structural remodeling: the potential mechanism to mediate the relationship between obstructive sleep apnea and cardiac arrhythmias.

Cardiac arrhythmias are very common in patients with obstructive sleep apnea (OSA), especially atrial fibrillation (AF) and nonsustained ventricular tachycardia (NVST). Cardiac autonomic dysfunction and structural remodeling caused by OSA provide the milieu for cardiac arrhythmia development. This study aimed to determine whether OSA is associated with various cardiac arrhythmias and investigate potential pathophysiologic pathways between them. The analysis covered 600 patients with clinical suspicion of OSA hospitalized in Renmin Hospital of Wuhan University between January 2020 and May 2023. After undergoing sleep apnea monitor, all subjects received laboratory tests, Holter electrocardiography, and Echocardiography. Compared with those without OSA and adjusting for potential confounders, subjects with moderate OSA had three times the odds of AF (odds ratio [OR] 3.055; 95% confidence interval [CI], 1.002-9.316; p = 0.048). Subjects with severe OSA had three times the odds of AF (OR 3.881; 95% CI, 1.306-11.534; p = 0.015) and NSVT (OR 3.690; 95% CI, 0.809-16.036; p = 0.046). There were significant linear trends for the association between OSA severity with AF and NVST (p < 0.05). And this association was mediated by cardiac structural changes including left atrial diameter, left ventricular diastolic diameter, right atrial diameter and right ventricular diameter. In addition, the ratio of low-frequency and high-frequency individually mediated the association between severe OSA and NVST. This study demonstrated that severe OSA was independently associated with AF and NSVT, and this association was mediated by autonomic nervous system changes and cardiac structural remodeling.

Continuous Long-Term Assessment of Heart Rate Variability in Adults with Cyanotic Congenital Heart Disease after Surgical Repair.

Background: Heart rate variability (HRV) is an established, non-invasive parameter for the assessment of cardiac autonomic nervous activity and the health status in general cardiology. However, there are few studies on HRV in adults with congenital heart defects (CHDs). The aim of the present study was to evaluate the use of long-term continuous HRV measurement for the assessment of global health status in adults with cyanotic CHD. Methods: This prospective study included 45 adults (40% female, mean age = 35.2 ± 9.2 [range: 19-58] years) after cardiac surgical repair. HRV parameters were calculated from continuous 24 h measurements using a Bittium Faros 180 sensor (Bittium Corp., Oulu, Finland). Results: Postoperative patients with transposition of the great arteries (TGA) (n = 18) achieved significantly higher values of standard deviation of NN intervals (SDNN) (175.4 ± 59.9 ms vs. 133.5 ± 40.6 ms; p = 0.013) compared with patients with other conotruncal anomalies (n = 22). Comparing patients with TGA after a Senning-Brom or Mustard operation (n = 13) with all other heart surgery patients (n = 32), significantly higher HRV parameters were found after atrial switch (root mean square of successive RR interval differences: 53.6 ± 20.7 ms vs. 38.4 ± 18.3 ms; p = 0.019; SDNN: 183.5 ± 58.4 ms vs. 136.3 ± 45.3 ms; p = 0.006). A higher SDNN was also measured after Senning-Brom or Mustard operations than after a Rastelli operations (n = 2) (SDNN: 183.5 ± 58.4 ms vs. 84.5 ± 5.2 ms; p = 0.037). When comparing atrial switch operations (n = 3) with Rastelli operations, the SDNN value was significantly shorter in the Rastelli group (p = 0.004). Conclusions: Our results suggest that continuous HRV monitoring may serve as a marker of cardiac autonomic dysfunction in adults with cyanotic CHD after surgical repair. Impaired cardiac autonomic nervous activity may be associated with an increased risk of adverse reactions in patients with repaired CHD. Therefore, a longitudinal assessment of HRV patterns and trends may provide a deeper insight into dynamic changes in their autonomic regulation and disease progression, lifestyle changes, or treatments. As each person has individual variability in heart rate, HRV may be useful in assessing intra-individual disease progression and may help to improve personalized medicine. Further studies are needed to better understand the underlying mechanisms and to explore the full potential of HRV analysis to optimize medical care for ACHDs.

Prevalence and predictors of preoperative cardiac autonomic dysfunction among elective neurosurgical patients: A prospective observational study.

The autonomic nervous system (ANS) is cardinal for systemic homeostasis. Autonomic dysfunction is prevalent in as high as 65% of patients presenting for cardiac surgery in the Indian scenario. Pre-existing cardiac autonomic dysfunction (CAD) in surgical patients can accentuate perioperative haemodynamic fluctuations during stressful intraoperative events, predispose to adverse cardiac events, and contribute to morbidity and mortality. The prevalence and predictors of CAD in the elective neurosurgical population are unknown in the Indian scenario. The current study was conducted to bridge this knowledge gap. In this single-centre prospective observational study conducted at a tertiary care neurosciences centre, among 400 consenting adult patients of either gender, between 18 and 80 years of age, undergoing elective neurosurgery, the preoperative ANS function at the bedside was assessed as the primary outcome measure. The ANS status was evaluated using ANSiscope™-derived indices of heart rate variability. The diagnosis of CAD was made when the ANS index exceeded a threshold of 13.5. Data regarding predictors of CAD were collected from patient records as the secondary outcome measure. Statistical analysis was done using the R software. A P-value of <0.05 was considered statistically significant. The prevalence of preoperative CAD in our study population was 79.7% (319/400 patients). None of the demographic and baseline clinical characteristics we studied predicted CAD in our study. We observed a significant prevalence of preoperative CAD among elective neurosurgical patients. None of the parameters we evaluated predicted CAD in our study.

Hemodialysis Efficiency Predictor in End-Stage Kidney Disease Using Real-Time Heart Rate Variability.

Autonomic dysfunction as a long-term complication may occur in end-stage kidney disease (ESKD) patients and can be diagnosed using heart rate variability (HRV) analyzed from electrocardiogram (ECG) recordings. There is limited data about HRV using real-time ECG to predict hemodialysis (HD) efficiency in patients with ESKD who are routinely doing HD in the real world. A total of 50 patients (62.1 ± 10.7 years) with ESKD underwent continuous real-time ECG monitoring (237.4 ± 15.3 min) during HD for HRV using remote monitoring system. Their electrolyte levels were checked before and after HD. We compared HRV according to electrolyte levels. During the monitor, we checked the ECG and electrolyte levels simultaneously a total of 2374 times for all of the patients. Both time and frequency domain HRV were higher when the patients had lower K+ level (<0.5 mEq/L) and P+ level change (<2 mEq/L) before and after HD as compared to those with a higher K+ level (≥0.5 mEq/L) and P+ level change (≥2 mEq/L). Additionally, patients with lower K+ and P+ level change groups had higher incidences of arrhythmic events including atrial/ventricular premature complexes, despite no difference of mean heart rate (p < 0.001). Higher HRV was independently associated with a poorly controlled K+ and P+ level during HD in patients with ESKD. This is consistently evidenced by the independent association between higher HRV, K+ and P+ levels in real time, suggesting that low electrolyte changes before and after HD alone may cause cardiac autonomic dysfunction.

Predictors of Cardiac Autonomic Dysfunction in Obesity-Related Hypertension.

Cardiac Autonomic Dysfunction (CAD) is an overlooked cardiovascular risk factor in individuals with obesity-related hypertension. Despite its clinical significance, there is a notable lack of clarity regarding the pathophysiological correlates involved in its onset and progression. The present study aimed to identify potential predictors of CAD in obesity-related hypertension. A total of 72 participants (34 men and 38 women) were enrolled. Comprehensive evaluations were conducted, including cardiac autonomic function assessments, body composition estimation and biochemical analysis. Participants were categorized as CAD-positive or CAD-negative based on Ewing's criteria for autonomic dysfunction. Univariate logistic regression analysis was performed to identify potential predictors for CAD. Multivariate logistic regression models were further constructed by adjusting clinically relevant covariates to identify independent predictors of CAD. Multivariate logistic regression analysis revealed that resting heart rate (HRrest), (odds ratio, confidence interval: 0.85, 0.78-0.93; p = 0.001) and percentage body fat (BF%), (odds ratio, confidence interval: 0.78, 0.64-0.96; p = 0.018) were significant independent predictors of CAD. Receiver Operating Characteristic curve analysis depicted optimal cut-off values for HRrest and BF% as >74.1bpm and >33.6%, respectively. Multicolinearity analysis showed variance inflation factors (VIF) below the cautionary threshold of 3. The HRrest and BF% emerged as significant independent predictors of CAD in obesity-related hypertension. Therapeutic strategies should target HRrest<74.1bpm and BF% <33.6% to mitigate CAD risk in this population. Future trials are required to establish causal relationships and may consider additional confounding variables in obesity-related hypertension.

Cardiac autonomic function is preserved in young adults with major depressive disorder.

The prevalence of major depressive disorder (MDD) is highest in young adults and contributes to an increased risk of developing future cardiovascular disease (CVD). However, the underlying mechanisms remain unclear. The studies examining cardiac autonomic function that have included young unmedicated adults with MDD report equivocal findings, and few have considered the potential influence of disease severity or duration. We hypothesized that heart rate variability (HRV) and cardiac baroreflex sensitivity (BRS) would be reduced in young unmedicated adults with MDD (18-30 yr old) compared with healthy nondepressed young adults (HA). We further hypothesized that greater symptom severity would be related to poorer cardiac autonomic function in young adults with MDD. Heart rate and beat-to-beat blood pressure were continuously recorded during 10 min of supine rest to assess HRV and cardiac BRS in 28 HA (17 female, 22 ± 3 yr old) and 37 adults with MDD experiencing current symptoms of mild-to-moderate severity (unmedicated; 28 female, 20 ± 3 yr old). Neither HRV [root mean square of successive differences between normal heartbeats (RMSSD): 63 ± 34 HA vs. 79 ± 36 ms MDD; P = 0.14] nor cardiac BRS (overall gain, 21 ± 10 HA vs. 23 ± 7 ms/mmHg MDD; P = 0.59) were different between groups. In young adults with MDD, there was no association between current depressive symptom severity and either HRV (RMSSD, R2 = 0.004, P = 0.73) or cardiac BRS (overall gain, R2 = 0.02, P = 0.85). Taken together, these data suggest that cardiac autonomic dysfunction may not contribute to elevated cardiovascular risk factor profiles in young unmedicated adults with MDD of mild-to-moderate severity.NEW & NOTEWORTHY This study investigated cardiac autonomic function in young unmedicated adults with major depressive disorder (MDD). The results demonstrated that both heart rate variability and cardiac baroreflex sensitivity were preserved in young unmedicated adults with MDD compared with healthy nondepressed young adults. Furthermore, in young adults with MDD, current depressive symptom severity was not associated with any indices of cardiac autonomic function.

Quantification of lipoproteins by proton nuclear magnetic resonance spectroscopy (1H-NMRS) improves the prediction of cardiac autonomic dysfunction in patients with type 1 diabetes.

To assess if advanced characterization of serum glycoprotein and lipoprotein profile, measured by proton nuclear magnetic resonance spectroscopy (1H-NMRS) improves a predictive clinical model of cardioautonomic neuropathy (CAN) in subjects with type 1 diabetes (T1D). Cross-sectional study (ClinicalTrials.gov Identifier: NCT04950634). CAN was diagnosed using Ewing's score. Advanced characterization of macromolecular complexes including glycoprotein and lipoprotein profiles in serum samples were measured by 1H-NMRS. We addressed the relationships between these biomarkers and CAN using correlation and regression analyses. Diagnostic performance was assessed by analyzing their areas under the receiver operating characteristic curves (AUCROC). Three hundred and twenty-three patients were included (46% female, mean age and duration of diabetes of 41 ± 13years and 19 ± 11years, respectively). The overall prevalence of CAN was 28% [95% confidence interval (95%CI): 23; 33]. Glycoproteins such as N-acetylglucosamine/galactosamine and sialic acid showed strong correlations with inflammatory markers such as high-sensitive C-reactive protein, fibrinogen, IL-10, IL-6, and TNF-α. On the contrary, we did not find any association between the former and CAN. A stepwise binary logistic regression model (R2 = 0.078; P = 0.003) retained intermediate-density lipoprotein-triglycerides (IDL-TG) [β:0.082 (95%CI: 0.005; 0.160); P = 0.039], high-density lipoprotein-triglycerides (HDL-TGL)/HDL-Cholesterol [β:3.633 (95%CI: 0.873; 6.394); P = 0.010], and large-HDL particle number [β: 3.710 (95%CI: 0.677; 6.744); P = 0.001] as statistically significant determinants of CAN. Adding these lipoprotein particles to a clinical prediction model of CAN that included age, duration of diabetes, and A1c enhanced its diagnostic performance, improving AUCROC from 0.546 (95%CI: 0.404; 0.688) to 0.728 (95%CI: 0.616; 0.840). When added to clinical variables, 1H-NMRS-lipoprotein particle profiles may be helpful to identify those patients with T1D at risk of CAN.

Relationship between dust allergen sensitization and cardiac autonomic function in patients with chronic obstructive pulmonary disease.

Cardiac autonomic function predicts cardiovascular disease risk. The aim of this study was to investigate the relationship between sensitization to dust allergens and cardiac autonomic dysfunction in patients with chronic obstructive pulmonary disease (COPD), and to provide new ideas for the prevention of cardiovascular complications in these patients. Immunoassays for sensitization to cats/dogs, cockroaches and dust mites were performed in 840 patients with COPD. Indicators of heart rate variability in these patients were used to assess cardiac autonomic function, including standard deviation of normal-to-normal intervals (SDNN), root-mean square of successive differences between normal-to-normal intervals (RMSSD), low-frequency power (LF), high-frequency power (HF), and LF/HF ratios, which were obtained based on ambulatory electrocardiographic monitoring data. The relationship between sensitization to these dust allergens and heart rate variability was explored using multivariate logistic regression. The multivariate analyses showed that sensitization to total allergens was associated with reduced levels of SDNN, RMSSD, LF and HF and with increased levels of the LF/HF ratio in the patients with COPD (p < .05). Dust allergen sensitization may be associated with cardiac autonomic dysfunction in patients with COPD. Whether desensitization can prevent cardiovascular complications in these patients should be further explored.

Comparison of time domain indices of heart rate variability between alcohol-dependent individuals and non-alcoholic subjects

Background: Alcohol dependence develops because of repeated alcohol intake. Alcohol damages the cardiac autonomic nerve fibers leading to autonomic imbalance, resulting in reduced heart rate variability (HRV). HRV refers to the complex beat-to-beat variation in the heart rate, produced by the interplay of sympathetic and parasympathetic neural activity at the Sino-atrial node. Our body works effectively in parasympathetic activity dominance. The time domain indices of HRV are specific markers of parasympathetic activity. A decrease in the time domain parameters indicates reduced parasympathetic activity in the heart, indicating cardiac autonomic dysfunction with vagal neuropathy. Aims and Objectives: The objectives of the study are as follows: (1) To assess the HRV in alcohol-dependent individuals using time domain indices. (2) To compare the HRV between alcoholic-dependent individuals and non-alcoholic subjects. Materials and Methods: A total of 110 individuals in the age group of 20–55 years were recruited for our study. Among them, 55 were alcohol-dependent individuals selected based on the diagnostic and statistical manual-IV, international classification of diseases-10 criteria, and 55 age and gender-matched volunteers were selected as healthy non-alcoholic controls. Short-term HRV was recorded in a supine posture, and the results were interpreted. Statistical analysis was done using the software SPSS version 21.0. Results: Our results showed a significant reduction in the time-domain parameters of HRV – SDNN, RMSSD, NN50, and pNN50 in the alcohol-dependent individuals compared to the controls, suggesting reduced parasympathetic activity in the heart indicating cardiac autonomic neuropathy. Conclusion: Alcohol affects the cardiac autonomic status leading to sudden death due to arrhythmias. HRV can be used as a non-invasive test to assess cardiac autonomic dysfunction and its biofeedback can help alcohol-dependent individuals to adopt healthy lifestyle measures.

A cross-sectional comparative assessment of diabetic autonomic neuropathy using heart rate variability and galvanic skin response – Effect of disease progression

Background: Type 2 diabetes mellitus (T2DM) poses a significant health-care challenge and is a primary contributor to both mortality and morbidity. Diabetic autonomic neuropathy (DAN) is a frequently occurring complication associated with diabetes mellitus. Autonomic nerve damage leading to cardiac autonomic dysfunction and peripheral sympathetic neuropathy can lead to changes in heart rate variability (HRV) and galvanic skin resistance (GSR), respectively. Aims and Objectives: The study was designed and done to evaluate the impact of T2DM on HRV and GSR for assessing DAN. Materials and Methods: A total of 100 individuals diagnosed with T2DM (cases) and 100 healthy individuals (controls) participated in this study. Physio Pac (PC-2004) was used to record the necessary data. Statistical analysis was performed using the non-parametric Mann–Whitney test to see the comparison of the cases and controls. In addition, to measure the statistical relationship between the duration of the disease and the HRV and GSR parameters, Spearman’s rank correlation coefficient was utilized. The study received approval from the Ethical and Research Committee at the Government Medical College, Patiala. Results: Significant statistical differences were observed between the cases and controls in all time domain measures, as well as GSR and the majority of frequency domain measures of HRV. The correlation analysis revealed a strong association between the duration of T2DM and a decrease in HRV as well as an increase in GSR. Conclusion: The findings from the present study provide evidence that T2DM has an impact on HRV, which suggests the presence of cardiac autonomic neuropathy among diabetic patients, leading to an increased risk of cardiovascular morbidity. In addition, the study indicates that reduced sudomotor function, as assessed by Galvanic Skin Resistance (GSR), serves as a predictive measure for autonomic neuropathy. Therefore, these tests can serve as valuable tools in facilitating the assessment of DAN.

Cardiac Autonomic Dysfunction Measured as Reduced Heart Rate Variability, in the Intermediate Post-Covid State in Men

Abstract Background: A critical illness such as severe coronavirus disease 2019 (COVID-19) activates autonomic, endocrine, and emotional stress responses. Whether the manifestations of excessive stress experience persist beyond full recovery into the intermediate post-COVID period (3–6 months after recovery) is not known and was the question we addressed in the current study. Methods: An analytical observational cross-sectional study compared the heart rate variability (HRV), 8 AM serum cortisol concentration, and the Depression, Anxiety, and Stress Scale–21 (DASS-21) scores between COVID-19 recovered participants and their age-matched control subjects (21 male participants, 30–70 years of age, in each group). Results: The median (Q1–Q3) of low frequency (LF), high frequency (HF), and total powers of HRV was significantly reduced in those who recovered from severe COVID-19, compared to control subjects (respectively LF power: 410.871 [245.10–861.94], 947.57 [536.11–1778.55], P = 0.011; HF power: 192.916 [87.66–564.43], 705.18 [248.67–1192.19] P = 0.013; Total power: 646.33 [308.72–1518.28], 1613.33 [956.14–4022.55] P = 0.015, Mann–Whitney U-test). Serum cortisol and DASS-21 scores were not different from the control group. Conclusions: Impaired cardiac autonomic function, evidenced by reduced HRV, was observed in the intermediate period following recovery from severe COVID-19. However, psychological stress and elevated serum cortisol were not noted. Our result that exposes the effect of COVID-19 on cardiac autonomic responsiveness is important as diminished HRV increases the vulnerability of COVID-19 survivors to diseases. These findings may also suggest a focus of therapy in them, as specific interventions are known to improve HRV and cardiac autonomic functioning.

Study of subclinical chronotropic response to acute exercise in children of type 2 diabetic parents

Background: Type 2 diabetes mellitus (T2DM) has multiple pathogenesis. Hereditary propagation marks the genetic role as a very certain factor in the causation of T2DM. Reports have suggested that individuals with a family history (FH) of T2DM exhibit an altered chronotropic response even before the manifestations of the disease. Physical exercise is a proven way to extract any of the underlying cardiovascular abnormalities. These abnormalities may not be present during rest and identifying them can be useful as a good estimate of the individual’s cardiac functional sufficiency. After the stoppage of exercise, heart rate recovery (HRR) gives a thought toward the consideration of the coordinated equilibrium of the parasympathetic and sympathetic neural pathways. The withdrawal of the sympathetic influence and simultaneous parasympathetic reactivation make HRR as a measure of the underlying autonomic dysfunction. The early outcomes of cardiac effects in healthy children of T2DM parents were studied. Any evidence of changes observed will suggest that such individuals can avert and retard the genetically propagated diseases by following an appropriate healthy lifestyle. Aims and Objectives: (1) To assess subclinical cardiac autonomic dysfunction by way of an episode of acute aerobic exercise and study heart rate (HR), HRR, and blood pressure (BP) parameters in children of T2DM. (2). To compare above assessment parameters among the 2 groups - children of T2DM and children of non-diabetic parents. Materials and Methods: The present study is a cross-sectional observational study comprising 120 subjects in the age group of 18–40 years, 60 Cases – children of T2DM parents and 60 age-matched Controls – children of non-diabetic parents. HR and BP were measured at rest, during exercise, immediately after (Peak HR and BP), 10 min, 20 min, and 30 min after completion of exercise. An automated multipara monitor (RMS-Phoebus P513) was used to record these parameters. An informed written consent and ethics committee approval from the institution was taken. All data were summarized and statistically analyzed. Values for statistical analysis are expressed as Mean ± standard deviation (SD) and for statistical significance, P &lt; 0.05 was considered. Results: Basic attributes, anthropometry of both cases and controls were comparable. Blood glucose parameters despite being in normal range, were higher in cases (P &gt; 0.05). HR, BP parameters at rest, and their response (behavior) to exercise were similar in both groups. Cases had an increased HR and BP with an increase in exercise duration, at peak exercise and during the early phase of recovery but returned to baseline levels following a total recovery period (30 min). Conclusion: Young euglycemic, non-diabetic children of T2DM parents have an altered chronotropic response to exercise. There is an increased HR and BP response during peak exercise, beginning and early phase of the recovery period. Such a dysregulation is probably suggestive of higher cardiovascular risk. This emphasizes a healthy lifestyle and early detection.

Hemodynamic effects of etomidate anesthesia induction in diabetic and non-diabetic patients: Importance of heart rate variability in early detection of cardiac autonomic dysfunction

Aims: Cardiovascular diseases represent the primary cause of perioperative morbidity among diabetic patients. Etomidate, an anesthetic agent with minimal cardiovascular effects, is commonly used in these patients. Diabetic patients often experience cardiovascular autonomic neuropathy, a severe complication of diabetes. In recent years, measuring heart rate variability has become increasingly important for early detection of cardiac autonomic dysfunction. The aim of this study was to compare the hemodynamic effects of etomidate anesthesia induction between diabetic and non-diabetic patients. Methods: This was a prospective randomized study that enrolled consecutive ASA I-III patients scheduled for various elective surgeries under general anesthesia. The patients were divided into two groups: Group D (diabetic, n = 21) and Group ND (non-diabetic, n = 21). Heart rate variability analyses were performed using a Norav-800 Holter on the day before surgery. On the day of the operation, after premedication and monitoring, general anesthesia was induced with etomidate. Hemodynamic parameters were measured before induction (T1), after induction (T2), and 2 min (T3), 5 min (T4), and 10 min (T5) after endotracheal intubation. Hemodynamic changes and heart rate variability were compared between the two groups. Results: Group D showed a statistically significant decrease in systolic arterial pressure values at T2, T4, and T5 compared to baseline values (p &lt; 0.001), while Group ND showed no significant differences in any period. Diastolic blood pressure decreased significantly in Group D compared to baseline values in the preintubation period (p &lt; 0.001), but there was no significant change in Group ND. Heart rate did not significantly differ between the two groups during any measurement period, and there was no correlation between heart rate variability and hemodynamic changes. Conclusion: The results suggest that etomidate anesthesia induction provides hemodynamic stability in patients with type 2 diabetes mellitus. Despite its potential utility, heart rate variability measured during resting conditions may not provide sufficient diagnostic accuracy for predicting the presence of autonomic neuropathy, particularly in individuals with diabetes mellitus.Therefore, additional measures may be needed for early detection of cardiac autonomic dysfunction in these patients.

Cardiac autonomic dysfunction in a mouse model of carcinoid disease

Cardiac autonomic dysfunction in a mouse model of carcinoid disease

Explorative study to assess cardiac autonomic dysfunction in patients with juvenile myoclonic epilepsy

Explorative study to assess cardiac autonomic dysfunction in patients with juvenile myoclonic epilepsy

Real-time heart rate variability according to ambulatory glucose profile in patients with diabetes mellitus.

Autonomic neuropathy commonly occurs as a long-term complication of diabetes mellitus (DM) and can be diagnosed based on heart rate variability (HRV), calculated from electrocardiogram (ECG) recordings. There are limited data on HRV using real-time ECG and ambulatory glucose monitoring in patients with DM. The aim of this study was to investigate real-time HRV according to ambulatory glucose levels in patients with DM. A total of 43 patients (66.3 ± 7.5 years) with DM underwent continuous real-time ECG monitoring (225.7 ± 107.3 h) for HRV and ambulatory glucose monitoring using a remote monitoring system. We compared the HRV according to the ambulatory glucose profile. Data were analyzed according to the target in glucose range (TIR). There were no significant differences in the baseline characteristics of the patients according to the TIR. During monitoring, we checked ECG and ambulatory glucose levels (a total of 15,090 times) simultaneously for all patients. Both time- and frequency-domain HRVs were lower when the patients had poorly controlled glucose levels (TIR < 70%) compared with well controlled glucose levels (TIR > 70%). In addition, heart and respiratory rates increased with real-time glucose levels (P < 0.001). Poorly controlled glucose levels were independently associated with lower HRV in patients with DM. This was further substantiated by the independent continuous association between real-time measurements of hyperglycemia and lower HRV. These data strongly suggest that cardiac autonomic dysfunction is caused by elevated blood sugar levels.

Anthracycline's Effects on Heart Rate Variability in Children with Acute Lymphoblastic Leukemia: Early Toxicity Signs-Pilot Study.

Anthracycline treatments are known to cause cardiotoxic long-term side effects in cancer survivors. Recently, a decrease in heart rate variability (HRV) has been identified in these patients, signaling autonomic dysfunction and altered cardiac fitness. This study aimed at evaluating changes in HRV in children treated with anthracyclines. A total of 35 pediatric patients with acute lymphoblastic leukemia were evaluated by means of a 24 h Holter ECG, at baseline and after reaching half the total cumulative dose of doxorubicin equivalent (120 mg/m2). Parameters of HRV were assessed, as well as any arrhythmic episodes, bradycardia and tachycardia percentages. The results showed a significant decrease in both time-domain and frequency-domain HRV parameters, following anthracycline treatment. The low-frequency (LF) to high-frequency (HF) parameters' ratio also displayed a significant difference (p = 0.035), suggestive of early cardiac autonomic dysfunction. Of note, none of the patients presented symptoms of heart disease or elevated troponins, and only two patients presented echocardiographic signs of diastolic dysfunction. The present study showed that cardiac autonomic nervous system regulation is compromised in children treated with anthracyclines even before reaching the total cumulative dose. Therefore, HRV parameters could be the first indicators of subclinical cardiac toxicity, making Holter ECG monitoring of the oncological patient a necessity.