Autonomic Dysfunction Research Articles

Prevalence of self-reported symptoms of diabetic autonomic dysfunction in the North Denmark Region: a population-based survey.

Diabetic autonomic neuropathy is a severe complication of diabetes, estimated to affect up to 44% in type 1 diabetes (T1D) and 73% in type 2 diabetes (T2D) based on clinical studies. Currently, the assessment of diabetic autonomic neuropathy is not implemented in Denmark's clinical guidelines, complicating the estimation of the true prevalence. Thus, this study investigated the prevalence of self-reported symptoms of autonomic dysfunction in people living with diabetes in the North Denmark Region using the Composite Autonomic Symptoms Score (COMPASS)-31 questionnaire. In 2022, all adults with T1D or T2D in the North Denmark Region (n = 29,155) were identified using The National Health Insurance Service Registry and invited to an online survey including the Danish version of COMPASS-31. The prevalence and associated 95% confidence intervals (CI) for symptomatic autonomic dysfunction were determined using a cut-off value of 16. In total, 7,377 completed COMPASS-31, of which 82.4% reported having T2D and 13.7% T1D. The prevalence of symptomatic autonomic dysfunction was 36.8% (95% CI: 34-40) after a median of 26 years with diabetes for T1D and 44.2% (95% CI: 43-45) after a median of 10 years for T2D. Pupillary and orthostatic intolerance were the most frequent moderate to severe symptoms, respectively (38.4% and 24.0% in T1D and 32.8% and 26.3% in T2D). Symptoms of autonomic dysfunction are very common in individuals with diabetes living in the North Denmark Region, emphasizing the unmet need for regular testing to increase awareness and allow for adequate management, ultimately reducing the morbidity of diabetes.

Case report: Combined transcutaneous spinal cord stimulation and physical therapy on recovery of neurological function after spinal cord infarction

The case of a 37-year-old woman who suffered from spinal cord infarction (SI), resulting in a complete spinal cord injury (AIS A, neurological level T10), and autonomic dysfunction is presented. This study aimed to assess the effect of transcutaneous Spinal Cord Electrical Stimulation (tSCS) on improving motor, sensory, and autonomic function after SI. During the first 8 months, tSCS was applied alone, then, physical therapy (PT) was included in the sessions (tSCS+PT), until completion of 20 months. Compared to baseline, at 20 months, an increase in ISNCSCI motor (50 vs. 57) and sensory scores (light touch, 72 vs. 82; pinprick, 71 vs. 92) were observed. Neurogenic Bladder Symptoms Score (NBSS) changed from 27 at baseline to 17 at 20 months. ISAFSCI scores in sacral autonomic function improved from 0 pts (absent function) to 1 pt. (altered function) indicating better sphincter control. EMG recordings during volitional movements, including overground stepping with 80% of body weight support showed activity in gluteus medialis, tensor fascia latae, sartorius, rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius medialis, indicating a partial reversion of paralysis. RMS analysis indicated higher activity during “tSCS on” compared to “tSCS off” during overground stepping in bilateral rectus femoris (p < 0.001) and gastrocnemius medialis (p < 0.01); and unilateral biceps femoris, and tibialis anterior (p < 0.001). As this is the first report on the use of tSCS in the case of SI, future studies in a case series are warranted.

Polygenic risk for psychotic disorders in relation to cardiac autonomic dysfunction in unmedicated patients with schizophrenia.

Cardiac autonomic dysfunction (CADF), mainly characterized by increased heart rate, decreased heart rate variability, and loss of vagal modulation, has been extensively described in patients with schizophrenia (SCZ) and their healthy first-degree relatives. As such, it represents an apparent physiological link that contributes to the increased cardiovascular mortality in these patients. Common genetic variation is a putative underlying mechanism, along with lifestyle factors and antipsychotic medications. However, the extent to which CADF is associated with genetic factors for SCZ is unknown. A sample of 83 drug-naive SCZ patients and 96 healthy controls, all of European origin, underwent a 30-minute autonomic assessment under resting conditions. We incorporated parameters from several domains into our model, including time and frequency domains (mean heart rate, low/high frequency ratio) and compression entropy, each of which provides different insights into the dynamics of cardiac autonomic function. These parameters were used as outcome variables in linear regression models with polygenic risk scores (PRS) for SCZ as predictors and age, sex, BMI, smoking status, principal components of ancestry and diagnosis as covariates. Of the three CADF parameters, SCZ PRS was significantly associated with mean heart rate in the combined case/control sample. However, this association was was no longer significant after including diagnosis as a covariate (p = 0.29). In contrast, diagnostic status is statistically significant for all three CADF parameters, accounting for a significantly greater proportion of the variance in mean heart rate compared to SCZ PRS (approximately 16% vs. 4%). Despite evidence for a common genetic basis of CADF and SCZ, we were unable to provide further support for an association between the polygenic burden of SCZ and cardiac autonomic function beyond the diagnostic state. This suggests that there are other important characteristics associated with SCZ that lead to CADF that are not captured by SCZ PRS.

Hypertension-induced heart failure disrupts cardiac sympathetic innervation.

About 26 million people worldwide live with heart failure (HF), and hypertension is the primary cause in 25% of these cases. Autonomic dysfunction and sympathetic hyperactivity accompany cardiovascular diseases, including HF. However, changes in cardiac sympathetic innervation in HF are not well understood. We hypothesized that cardiac sympathetic innervation is disrupted in hypertension-induced HF. Male and female C57BL6/J mice were infused with Angiotensin II (AngII) for 4 weeks to generate hypertension leading to HF; controls were infused with saline. AngII-treated mice displayed HF phenotype including reduced cardiac function, hypertrophy, and fibrosis. AngII-treated mice also had significantly reduced sympathetic nerve density in the left ventricle, intraventricular septum, and right ventricle. In the left ventricle, the subepicardium remained normally innervated, while the subendocardium was almost devoid of sympathetic nerves. Loss of sympathetic fibers led to loss of norepinephrine content in the left ventricle. Several potential triggers for axon degeneration were tested and ruled out. AngII-treated mice had increased premature ventricular contractions after isoproterenol and caffeine injection. Although HF can induce a cholinergic phenotype and neuronal hypertrophy in stellate ganglia, AngII treatment did not induce a cholinergic phenotype or activation of trophic factors in this study. Cardiac neurons in the left stellate ganglion were significantly smaller in AngII-treated mice, while neurons in the right stellate were unchanged. Our findings show that AngII-induced HF disrupts sympathetic innervation, particularly in the left ventricle. Further investigations are imperative to unveil the mechanisms of denervation in HF and to develop neuromodulatory therapies for patients with autonomic imbalance.

IGLON5 Frequency in Idiopathic REM Sleep Behavior Disorder: A Multicenter Study.

Idiopathic/isolated REM sleep behavior disorder (iRBD) has been strongly linked to neurodegenerative synucleinopathies such as Parkinson disease, dementia with Lewy bodies, and multiple system atrophy. However, there have been increasing reports of RBD as a presenting feature of serious and treatable autoimmune syndromes, particularly IGLON5. This study's objective was to investigate the frequency of autoantibodies in a large cohort of participants with iRBD. Participants were enrolled in the North American Prodromal Synucleinopathy cohort with polysomnography-confirmed iRBD, free of parkinsonism and dementia. Plasma samples were systematically screened for the autoantibodies IGLON5, DPPX, LGI1, and CASPR2 using plasma IgG cell-based assay. Positive or equivocal results were confirmed by repeat testing, plus tissue-based indirect immunofluorescence assay for IGLON5. Of 339 samples analyzed, 3 participants (0.9%) had confirmed positive IGLON5 autoantibodies in the cell-based assay, which were confirmed by the tissue-based assay. An additional participant was positive for CASPR2 with low titer by cell-based assay only (of lower clinical certainty). These cases exhibited a variety of symptoms including dream enactment, cognitive decline, autonomic dysfunction, and motor symptoms. In 1 IGLON5 case and the CASPR2 case, evolution was suggestive of typical synucleinopathy, suggesting the possibility that findings were incidental. However, 2 participants with IGLON5 died before diagnosis was clinically suspected, with a final clinical picture highly suggestive of autoimmune disease. Our finding that nearly 1% of a large iRBD cohort may have a serious but potentially treatable autoantibody syndrome has important clinical implications. In particular, it raises the question of whether autoantibody testing for IGLON-5-IgG should be widely implemented for participants with iRBD, considering the difficulty in diagnosis of autoimmune diseases, their response to treatment, and the potential for rapid disease progression. However, any routine testing protocol will also have to consider costs and potential adverse effects of false-positive findings. NCT03623672.

Clinically Probable Multiple System Atrophy Presenting Ptosis as an Early Manifestation

Many ocular features were found in patients with multiple system atrophy (MSA), which include dry eye, blepharospasm, eye movement problems, and blink reflex dysfunction. Some of these symptoms are associated with autonomic dysfunctions seen in MSA. We report a young clinically-probable MSA patient with bilateral ptosis at an early disease stage. Although there is no clear evidence that ptosis, in this case, was caused by abnormalities in the sympathetic cholinergic system, the selective impairment of sudomotor function implied an injured sympathetic cholinergic system secondary to MSA pathology. Ocular manifestations need more attention in clinical examinations of patients with MSA.

Familial adult-onset neuronal intranuclear inclusion disease: A case report and literature review.

Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disorder with highly variable clinical manifestations, making diagnosis challenging. Recent advancements in genetic and pathological testing, such as the identification of GGC repeat expansions in the NOTCH2NLC gene, have improved diagnostic accuracy, but familial cases remain underreported. This report details 3 cases of familial adult-onset NIID in 2 sisters and 1 brother. The older sister experienced episodic encephalopathy and autonomic dysfunction for over 40 years, while the younger sister presented similar symptoms 5 years ago. The brother also developed episodic encephalopathy 5 years ago. Brain diffusion-weighted imaging (DWI) for all 3 patients revealed hyperintensity at the corticomedullary junction and corpus callosum. Skin biopsies from the older sister and brother confirmed the presence of p62 antibody-positive intranuclear inclusion bodies in sweat gland cells and fibroblasts. Genetic testing showed 146 and 133 GGC repeats in the NOTCH2NLC gene in the older sister and brother, respectively. All 3 patients were diagnosed with NIID based on clinical, radiological, and genetic findings. The patients received hormonal therapy, circulation-enhancing treatments, and rehydration therapy during acute episodes. All 3 patients showed significant improvement in symptoms following treatment, with a return to baseline function after hospital discharge. Proper management of NIID includes prompt recognition of symptoms, adequate rest, and avoidance of triggers such as fatigue, infections, and stress, which may reduce the frequency of episodic attacks. Early diagnosis and targeted symptomatic treatment are essential for improving patient outcomes.

Cardiovascular Autonomic Dysfunction Before and After Chemotherapy in Cancer Patients.

Complications that occur during cancer therapy have emerged as a major contributor to the poor quality of life experienced by cancer patients as they live longer due to improved treatments. Many studies have investigated chemotherapy-induced peripheral neuropathy, but few have investigated the autonomic nervous system. Cardiovascular autonomic dysfunction (CAD) contributes to the distressing symptoms experienced by cancer patients, and it is also related to poor treatment outcomes. CAD has a multifactorial etiology in patients with cancer: it can be caused by the cancer itself, chemotherapy or radiation therapy, or other comorbidities. Its symptoms are nonspecific, and they include orthostatic hypotension, resting tachycardia, dizziness, chest tightness, and exertional dyspnea. It is important to suspect CAD and perform therapeutic interventions in a clinical context, because a patient who is more frail is less like to endure the treatment process. The quality of life of patients receiving active cancer treatments can be improved by evaluating the risk of CAD before and after chemotherapy, and combining both nonpharmacological and pharmacological management. Here we review the prevalence, pathogenesis, diagnosis, and treatment of CAD, which is the most common and a sometimes serious symptom in cancer patients.

Adverse cardiological and neurological reactions associated with air traffic and the possibility of their pharmacological correction

Air transport may provoke or aggravate a medical event in a passenger with concomitant medical problems. We searched the PubMed and Scopus databases for the period up to 08/29/2024 for sources that examined the impact of air travel on human health. There are 2 main categories of stressors associated with air travel and affecting the body, generally divided into:(1) psychological and physical stressors and (2) physiological Possible changes in health associated with air travel can be divided into functional, mostly reversible, and organic: (1) exacerbation/decompensation of existing somatic pathology;(2) development of pathological conditions de novo, for which possible stressors can serve as a trigger, directly or sequentially as a result of the previous development and progression of functional disorders. The literature focuses on safety issues during air travel for patients with existing cardiovascular pathology. Adverse functional cardiological and neurological reactions and their pharmacological correction have been less studied. Fear of flying and phobia of flying are very common among the general population and can lead to significant stress. For situational correction of reactions to everyday stressful events, it is possible to use drugs with anxiolytic action of a non-benzodiazepine This group includes the drug Valocordin®, the action of which is aimed at various manifestations of stress, anxiety states, autonomic dysfunction, increased excitability and irritability, mild sleep disorders. In case of pre-flight anxiety and fear, taking Valocordin® (depending on the situation or in a short course) can be the drug of choice for both the air traveler and his relatives seeing him off/meeting him.

The impact of high dose corticosteroid treatment affect on cardiac abnormalities in patients with multiple sclerosis

Aims: High-dose corticosteroids to control acute relapses of multiple sclerosis, leveraging their anti-inflammatory effects. However, these treatments can lead to cardiovascular side effects. Understanding the pathophysiology of corticosteroid induced bradycardia is paramount for healthcare providers. Our aim in this study are to identify risk factors for cardiac side effects and assess the timing of cardiac complications relative to treatment. Methods: Patients who met the McDonald's criteria for definite MS and patients requiring admission for pulse steroid treatment with an acute recurrence were included.Individuals taking cardiac medications, or with a heart illness were excluded.Patients were given 1 g IV methylprednisolone in 2 hours for five to seven days in order to treat acute relapses. Results: We studied with 23 patients(6 males and 17 females, 26.1/73.9% respectively).The mean±SD age of the patients was 34.6±9.9 (18-43) years and the mean±SD duration of disease was 5.5±4.9 years.Most of the patients were relapsing–remitting MS in 73.9%, primary progressive in 4.4% and secondary progressive in 21.7%.The most common cardiac arhythmia during corticosteroid pulse therapy was sinus bradycradia(n=6). Conclusion: The combination of direct effects on cardiac myocytes, electrolyte disturbances, autonomic dysfunction, and individual genetic factors can contribute to the development of bradycardia in MS patients treated with high-dose methylprednisolone. Close monitoring and prompt intervention are crucial to manage this adverse effect and optimize patient safety.

Cardiac autonomic dysfunction in Takotsubo cardiomyopathy: an observational study

Abstract Takotsubo syndrome (TTS), commonly perceived as a benign and reversible condition has received attention due to emerging registry data revealing its prognosis to be comparable to acute coronary syndrome (ACS). Following ACS, a notable subset of patients develops autonomic dysfunction, whith unfavourable prognostic implications. Periodic repolarization dynamics (PRD) and deceleration capacity (DC), derived from ECG signals, are parameters capable of quantifying cardiac autonomic function. In this study, we aimed to assess autonomic dysfunction in patients with TTC in comparison to ST-elevation myocardial infarction (STEMI) patients. Consecutive patients diagnosed with TTS were prospectively recruited into an observational, single-centre cohort study. All patients underwent a 30-minute high-resolution ecg recording. Subsequent recordings were conducted at 4 and 12 months post-acute event. PRD and DC as markers for sympathetic and parasympathetic activity, respectively, were assessed using established methods. The control group comprised patients with STEMI. Statistical comparisons between groups were performed using the Mann-Whitney U-test, with a corrected significance level for multiple testing of α< .017. Between July 2021 and December 2023, 57 patients diagnosed with TTS were recruited (interquartile range [IQR]) 69.0 years (62.0-78.0), 98.3% women. A control group was derived from a pre-existing cohort of STEMI patients, matched through propensity score matching to adjust for age and sex (median age [IQR]: 69.0 [59.0-76.0] years, 98.3% women). At baseline, there was no significant difference in PRD between TTS patients and controls (median [IQR]: TTS: 5.28deg² [3.43-9.93], STEMI: 4.40deg² [2.24-7.21]; p = .04). However, at 4 months post-acute event, PRD was notably higher in TTS patients compared to controls (median [IQR]: TTS: 5.20deg² [2.71-8.17], STEMI: 2.63deg² [1.86-4.92]; p = .011). Interestingly, at 12-month follow-up, PRD in TTS patients did not differ from that of controls (median [IQR]: TTS: 4.55deg² [2.89-8.40], STEMI: 4.15deg² [2.42-6.85]; p = .68). Regarding DC, no significant differences were observed between TTS and STEMI patients at any time point (baseline: median [IQR]: TTS: 3.95 ms [2.27-5.51], STEMI: 3.52 ms [2.30-7.24], p = .51; 4 months: median [IQR]: TTS: 6.63 ms [4.59-8.64], STEMI: 7.41 ms [4.63-9.25], p = .39; 12 months: median [IQR]: TTS: 4.98 ms [4.19-6.67], STEMI: 7.48 ms [4.92-10.28], p = .17). Patients with TTS show substantial signs of cardiac autonomic dysfunction, similar or even higher than acute STEMI patients. This dysfunction persists even up to 4 months after the acute event, whereas STEMI patients show recovery of autonomic function in this 4 month period. DC remained consistent between TTS and STEMI patients across all time points. Further research elucidating the long-term implications of these autonomic alterations is warranted to refine risk stratification and therapeutic strategies in TTS management.

Serum proteomic profiling reveals potential inflammatory biomarkers in long-COVID patients: a comparative analysis with healthy controls

Abstract Background Long-COVID (also known as post-acute sequelae of SARS-CoV-2 infection, PASC), is defined as the persistence, or the new onset, of symptoms after recovery from the acute phase of COVID-19. It consists of a multiorgan syndrome expressing itself with a wide variety of cardiovascular and non-cardiovascular symptoms such us chest pain, fatigue, shortness of breath, autonomic dysfunction, cognitive impairment and sleep disorders even in the absence of a clear evidence of organ dysfunction. Some previous studies have suggested the potential role of an abnormal inflammatory response after SARS-CoV-2 infection, however the specific underlying mechanisms remain unclear. In this study we performed a proteomic analysis of the serum of 80 long-COVID patients to identify potential biomarkers that may act as indicators or therapeutic targets for long COVID. Methods and results We compared the levels of the proteins in both long-COVID group and a control group using multivariate and univariate analysis. Both PLS-DA and PCA analysis showed a clear distinction between the two groups; clustering analysis also clearly separated control from long-COVID patients. Proteins were then filtered based on (a) statistical analysis, considering proteins with a VIP>1 (PLSDA) and p<0.05 (t-test); (b) coefficient of variation (CV), where only proteins with CV<10 were considered; (c) and fold change (FC), for which proteins with FC<0.67 or FC>1.5 were selected for further analysis. The selected proteins were then subjected to a ROC curve analysis to identify antithrombin as a potential biomarker with an area under the curve (AUC) near 1. Other proteins, displaying an AUC > 0.98, were also identified as potential biomarkers (Sirtuin 1, NatriureticPeptide B, Hemopexin Arachidonate 5-Lipoxygenase). In addition, a multivariate ROC method, using linear SVM as classification method, identified that a combination of ten proteins would also result in an AUC near 1. Finally, a correlation analysis between the proteins of interest and the clinical manifestations was performed. A positive correlation (above 0.5) was found between dyspnea and Glucocorticoid Receptor and between memory deficit and Antithrombin. Arachidonate 5-Lipoxygenase was negatively correlated (below -0.5) with tremors and hair loss, MannoseBinding Lectin 2 was found to be positively linked to asthenia, Antithrombin with concentration deficit and Endothelin-2 with muscles aches. Conclusions The identified biomarkers are associated with inflammatory processes, corroborating literature evidence that long-COVID patients develop an inflammatory state that damages many tissues. Further studies are needed to validate this data in larger cohorts to identify specific biomarkers, and guide future preventive strategies or treatments to address long COVID and its cardiovascular and non-cardiovascular sequelae.

Sustained paradoxical vasodilation and blood pressure lowering in response to sympathetic stimulation as markers of disease severity and poor survival in primary AL amyloidosis.

Abstract Background AL patients present sustained paradoxical vasodilation in response to sympathetic stimulation by cold pressor test (CPT). The clinical relevance of this finding is unknown. Purpose We investigated the association between CPT-induced vascular and hemodynamic responses with clinical characteristics of the disease in AL amyloidosis. Methods We consecutively recruited 113 newly diagnosed patients with AL amyloidosis before treatment initiation. High resolution ultrasonography was used to measure the maximum vasodilation of the brachial artery in response to a cold stimulus and 3 minutes after its withdrawal. Systolic (SBP) and diastolic blood pressure (DBP) were measured at the same timepoints. Clinical and laboratory makers of autonomic dysfunction were also measured in a subgroup of the population. All-cause and cardiovascular (CV) mortality were defined as end-points of the study. Results Sustained vasodilation post CPT (%pCPT) was associated with markers of autonomic dysfunction, namely dipping status (p<0.05) and sudomotor dysfunction (p=0.064) and with NYHA stage, baseline NTproBNP and heart failure (p<0.05 for all). DBP%pCPT was associated with the neuropathy symptom scale (NSS Autonomous, p=0.032), while SBP%pCPT was inversely associated with Mayo stage. Vasodilation%pCPT was independently associated with CV death (adjusted HR=1.154, p=0.017) while both DBP%pCPT (HR=0.955, p=0.027) and SBP%pCPT (HR=0.947, p=0.04) were independently associated with all cause death (adjusted for the core model including age, sex, SBP, Mayo stage and nerve involvement). Overall survival was worse in AL patients who demonstrated a decrease in SBP%pCPT than in those who exhibited an increase or kept it stable (log rank test, p=0.024). The same applies to DBP%pCPT(log rank test, p=0.002). Regarding CV death, Vasodilation%pCPT above 5.86% was associated with increased risk of CV death (log rank test, p=0.002). Conclusions In AL amyloidosis, sustained paradoxical vasodilation and decreased SBP and DBP in response to sympathetic stimulation were associated with autonomic dysfunction, more severe cardiac involvement and poor survival.

Association between autonomic dysfunction, 12-year mortality and 10-year incident cardiovascular disease

Abstract Background Standing from a supine position requires a co-ordinated response in peripheral and central haemodynamic signals to protect the brain and body from sudden drops in blood pressure (BP) and has previously been shown to be an important measure of neuro-cardiovascular health (1-3). Previous studies have found an association between BP and heart rate recovery (HRR) to standing with all-cause mortality, cardiovascular disease and other health outcomes (4-8). However, almost all of these studies have exclusively investigated the association of consensus-defined HR/BP phenotypes measured at specific timepoints during standing. Purpose We hypothesised that assessing information from the entire haemodynamic response to orthostasis - instead of discrete timepoints or consensus definitions - may uncover novel associations between BP/HR responses to active stand and neuro-cardiovascular health in older adults. This may afford better physiological understanding of the longitudinal relationships between the response to standing and both Cardiovascular Disease (CVD) and mortality. Methods We used functional Principal Components Analysis (FPCA) to examine the determinants of variability in the complete haemodynamic response to active stand and examine which components were related to mortality and incident CVD in >4500 community-dwelling adults aged 50+. Results Figure 1 shows the mean response curve according to mortality status and Figure 2 the mean curve for participants free of CVD at baseline who later have CVD vs those who remain CVD-free during 10 year follow-up. All-cause mortality was associated with functional principal components which discriminate higher baseline HR, blunted HR peak and impaired HRR up to ~25 seconds after standing. Components that discriminated high baseline and impaired recovery of SBP from the post-stand nadir to 60 seconds post stand were also associated with all-cause mortality. This association remained even after covariate adjustment. Interestingly, neither baseline SBP nor orthostatic hypotension (OH) were associated with mortality. Components which discriminate high baseline and blunted HR peak; elevated stroke volume index and impaired recovery of DBP from ~25 seconds post stand were associated with 10-year incident CVD. Conclusions To our knowledge this is the first study to incorporate data driven information over the entire trace of the haemodynamic response to standing to investigate associations with incident CVD and mortality. The fact that components which discriminated high BP and impaired recovery of BP were associated with 12-year mortality and 10-year incident CVD when traditional summary measures of OH and baseline BP were not; suggests that incorporating information across the entire response to standing allows for richer and more flexible associations with health outcomes to be uncovered and allows for a better understanding of the underlying physiology leading to such associations.Figure 1:Mean trace of Mortality StatusFigure 2:Mean Trace of CVD Status

Changes in blood metabolomes as potential biomarkers for severity and prognosis in doxorubicin-induced heart failure: a study in HER2-positive and HER2-negative breast cancer patients

Abstract Background The use of doxorubicin for breast cancer treatment is often limited due to cardiotoxicity. Doxorubicin was shown to cause the alterations of cardiac metabolome levels in doxorubicin-treated rats. Interestingly, these changes were robustly associated with the development of doxorubicin-induced heart failure. Unfortunately, measurements of cardiac metabolome levels are rarely possible in humans. Hence, non-invasive biomarkers as representatives of doxorubicin-induced heart failure are required in clinical research and practice. Human epidermal growth factor receptor 2 (HER2) is a point of interest in breast cancer treatment. HER2 is associated with tumor aggressiveness. However, it was observed that HER2 protected against systemic oxidative stress and dilated cardiomyopathy. Therefore, we hypothesized that the alterations of blood metabolome levels and cardiac functions following doxorubicin treatment were different between HER2-positive and HER2-negative breast cancer patients. Purpose We determined the potential roles of changes in blood metabolomes as severity and prognostic markers of doxorubicin-induced heart failure. In addition, the changes in blood metabolomes and cardiac parameters following doxorubicin treatment in HER2-positive and HER2-negative breast cancer patients were compared. Methods HER2-positive (n=37) and HER2-negative (n=37) breast cancer patients were enrolled. Echocardiography, heart rate variability, and blood collection were performed at baseline and 2 weeks after completion of doxorubicin treatment in all patients, as well as at 3 months after completion of doxorubicin treatment in HER2-negative breast cancer patients. Blood obtained at all 3 time points was processed for measuring cardiac injury markers. Blood obtained at baseline and 2 weeks after completion of doxorubicin treatment was also processed for measuring oxidative stress in peripheral blood mononuclear cells using flow cytometry and 85 metabolome levels in plasma using mass spectrometry-based targeted metabolomics. Results Cardiac injury and systolic dysfunction at 2 weeks after completion of doxorubicin treatment were comparable between HER2-positive and HER2-negative breast cancer 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 2 weeks after completion of doxorubicin treatment in HER2-positive and HER2-negative breast cancer patients, respectively (Figure). Interestingly, the changes in most of these metabolomes were correlated with the changes in cardiac parameters, both at 2 weeks and 3 months after completion of doxorubicin treatment (Figure). Conclusions The changes in blood metabolomes following doxorubicin treatment were dependent on HER2 status, which might be served as severity and prognostic markers of doxorubicin-induced heart failure.

Impact of atrial fibrillation on cardiac autonomic function in elderly patients

Abstract Introduction Cardiac autonomic dysfunction has been linked to an increased risk of mortality (1), stroke and silent brain lesions (2) and cognitive impairment (3) in patients with atrial fibrillation (AF). However, the impact of AF on cardiac autonomic function is poorly understood. Purpose We aimed to explore the impact of AF on cardiac autonomic function by comparing AF patients with a matched control cohort without AF. Methods We enrolled patients with and without AF from two ongoing, prospective, multicenter cohort studies (Swiss-AF Cohort and Swiss-AF Control) if they had a high-resolution 16-lead resting ECG recording in sinus rhythm for a duration of 5 minutes at baseline visit. Cardiac autonomic function was quantified by periodic repolarization dynamics (PRD), a marker of repolarization instability associated with sympathetic activity. PRD was quantified by means of wavelet analysis, as validated previously (4). Cardiac autonomic dysfunction was defined present if PRD exceeded the established cut-off of 10.0 deg2 (5). We built multivariable adjusted linear and logistic regression models to explore the association of AF with PRD and cardiac autonomic dysfunction. Results We included 2077 patients, 1113 (54%) from the AF cohort and 964 (46%) from the matched non-AF cohort. Baseline characteristics were well balanced between the groups (mean age 71 vs. 73 years in patients with and without AF, mean CHA2DS2-VASc score 3.0 vs. 3.5, female sex 31.3% vs. 36.6%). The median PRD was 18.2 deg2 (IQR 9.9-25.4) in patients with AF and 15.8 deg2 (IQR 8.1 -23.0) in patients without AF (p<0.001, Figure). 832 (75%) of the AF patients suffered from cardiac autonomic dysfunction, vs. 656 (68%) of the non-AF patients (p<0.001). Multivariable adjusted linear regression analysis revealed an independent association of AF with continuous levels of PRD (beta-coefficient -1.57, 95% CI -2.64 - -0.488, p=0.004). Further, AF was independently associated with the presence of cardiac autonomic dysfunction (Odds Ratio 1.48, 95% CI 1.18-1.87, p<0.001, Table). Conclusion In this cross-sectional analysis of a patient population with and without AF, AF was independently associated with increased PRD values, reflecting sympathetic predominance, and with the presence of cardiac autonomic dysfunction. These findings implicate a relevant role of AF in the development of cardiac autonomic dysfunction in elderly patients.Figure

Cardiac autonomic changes after stroke

Abstract Introduction There is a highly complex and clinically important relationship between the cardiac and the nervous system, called the heart-brain axis [1]. Therefore, acute brain damage may lead to alterations in cardiac function due to changes in the autonomic nervous system[2,3]. Novel computerised biosignal analysis techniques and advanced biosignal assessment could provide a valuable tool to sensitively analyse cardiac autonomic function (CAF). CAF can be characterized by two complementary digital biomarkers, periodic repolariation dynamics (PRD) and deceleration capacity (DC). The aim of this study was to determine CAF by means of PRD and DC in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA) and to analyze them according to their relationship with specific cardiac (high-sensitive Troponin T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-pro BNP)) and stroke (location, type, severity) characteristics. Methoden / Methods Between February 22, 2021, and May 5, 2023, 282 patients after an AIS or TIA were enrolled in the study. During the inpatient stay, all relevant parameters were recorded and stored in a database. To assess CAF, a 30-minute biosignal measurement was performed with a high resolution (1kHz) electrocardiogram (ECG). Cardiac autonomic biomarkers, PRD and DC, were calculated semiautomatically afterwards from patients. Results Fifteen ECGs were excluded due to poor recording quality. Consequently, data from 261 AIS and 21 TIA patients were analyzed. A total of 105 patients (37.2 %) had pathological PRD (≥ 5.75 deg2) and/or DC (≤ 2.5 ms), 78 patients (27.7 %) had pathological PRD, and 57 patients (20.2 %) had pathological DC. The median PRD was 3.13 deg2 and the median DC was 5.30 ms (see Figure). There were no significant differences in the distribution of PRD and DC between male and female patients (PRD p = 0.38, DC p = 0.30), and between AIS and TIA patients (PRD p = 0.13, DC p = 0.66). Patients with middle cerebral artery (MCA) infarction had significantly higher median PRD values (3.56 deg2 [IQR 1.51 - 6.59 ] vs. 2.81 deg2 [IQR 1.15 - 5.99], p = 0.047) and lower median DC values (4.66 ms [IQR 2.65 – 7.76] vs. 6.11 ms [IQR 3.15 – 10.61], p = 0.011) than patients with stroke located in another cerebral regions (see Figure). Patients with pathological PRD or DC had significantly higher hsTnT (13.50 ng/l [IQR 9.7 – 24.1] vs. 11.05 ng/l [ IQR 7.13 – 16.23], p < 0.001) and NT-pro BNP (269.00 ng/l [IQR 117.50 – 687.00] vs. 125.50 ng/l [IQR 57.00 – 288.25], p < 0.001) values. Conclusions The study showed that a considerable proportion, more than one third of all patients, had evidence of cardiac autonomic dysfunction after acute cerebral ischaemia. Of particular interest, PRD was higher and DC was lower in patients with MCA ischaemia, reflecting a potentially higher cardiac risk profile. Cardiac autonomic dysfunction was also associated with increased hsTnT and NT-proBNP levels.

Post-Exercise Syncope in a Previously Healthy 67-Year-Old Man: The Bezold–Jarisch Reflex and the Role of Autonomic Nervous System Dysfunction

A 67-year-old man started treatment due to frequent asymptomatic premature ventricular complexes (PVCs) accidentally being registered during a preventive examination by a specialist, because of which he was referred to cardiologist. During the initial 24-hour (h) ECG monitoring, 4.5% PVCs and one episode of asymptomatic non-sustained ventricular tachycardia (NSVT) with three PVCs in row, at a frequency of 150 beats per minute (bpm), were detected. After the introduction of beta blockers into therapy, a lower number of PVCs, without NSVT, were recorded in the control 24 h Holter ECG, while transthoracic echocardiography (TTE) showed normal left ventricular (LV) systolic function without cardiomyopathy. So, an exercise test was indicated, and it was interrupted in the third minute at 120 beats per minute (bpm) due to fatigue and pain in the hips, without malignant arrhythmias, angina or dyspneic complaints. During the rest period, a significant inferolateral depression of the ST junction was observed, which recovered in the ninth minute. Immediately after the ECG monitoring stopped, the patient lost consciousness; his pulse was not palpable, but breathing was audible, so cardiac massage was started. After he had regained consciousness, the ECG showed alternating sinus and junctional rhythm with the lowest frequency of 33 bpm, which was accompanied by marked hypotension (80/50 mmHg). The patient was immediately hospitalized; coronary angiography and repeated TTE were completely normal, while continuous ECG monitoring did not confirm malignant rhythm disorders or asystole. It was concluded that it was vasovagal syncope (VVS), most likely caused by the Bezold–Jarisch reflex (BJR).

Optimizing the anesthetic care of patients with aromatic l-amino acid decarboxylase deficiency.

Aromatic l-amino acid decarboxylase (AADC) deficiency is a rare autosomal recessive disorder that results in a lack of the monoamine neurotransmitters dopamine, serotonin, norepinephrine, and epinephrine. Patients present with a wide spectrum of symptoms, including motor and autonomic dysfunction, hypotonia, and developmental delay, often before the age of one. Until recently, treatment options were limited to symptom control, but the recent approval of the first gene therapy for AADC deficiency in Europe and the UK has provided an alternative to treating symptoms for this disease. Eladocagene exuparvovec is a one-time gene therapy, administered bilaterally to the putamen by magnetic resonance imaging-guided stereotactic neurosurgery. While administration of the gene therapy itself is minimally invasive, the anesthetic management of patients with AADC deficiency is challenging due to the absence of sympathetic regulation secondary to the lack of adrenergic neurotransmitters. Optimal anesthetic management requires an understanding of the complex and heterogeneous nature of the disease. Hemodynamic instability, temperature dysregulation, and hypoglycemia are of primary concern, but there are also challenges regarding intravenous access and airway management. A thorough preoperative assessment is essential and should be guided by the patient's history. Advanced planning is necessary regarding the timing of the procedure schedule and operative plan; meticulous preparation, simulation for the operating room, as well as communication with all perioperative staff members, are crucial. Intraoperatively, utmost care must be taken to protect the skin, maintain body temperature, and to prepare for inotropic and/or glycemic support as needed. Postoperative intensive care management is necessary for consideration of postoperative extubation and provision of supportive care. With careful planning, preparation, and vigilance, patients with AADC deficiency can safely undergo anesthesia.

Paroxysmal sympathetic hyperactivity syndrome after recurrent stroke: A case report

Paroxysmal sympathetic hyperactivity (PSH) is a state of autonomic dysfunction characterized by symptoms such as tachypnea, tachycardia, hypertension, hyperthermia, sweating, and dystonia. It can occur after traumatic brain injury, hypoxic-ischemic encephalopathy, and diseases such as stroke. Hypoxia, extensive axonal damage, and young age are believed to predispose to the development of PSH. These patients may be diagnosed with pulmonary embolism, septicemia, or epileptic seizures. Delays in diagnosis prolong hospital stay. Here, we present an 81-year-old man who developed PSH after a recurrent stroke and our management.