Assessment of Autonomic Nervous System Dysfunction in the Early Phase of Infection With SARS-CoV-2 Virus.

BACKGROUND: We are facing the outburst of coronavirus disease 2019 (COVID-19) defined as a serious, multisystem, disorder, including various neurological manifestations in its presentation. So far, autonomic dysfunction (AD) has not been reported in patients with COVID-19 infection. AIM: Assessment of AD in the early phase of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 virus). PATIENTS AND METHODS: We analyzed 116 PCR positive COVID-19 patients. After the exclusion of 41 patients with associate diseases (CADG), partitioned to patients with diabetes mellitus, hypertension, and syncope, the remaining patients were included into a severe group (45 patients with confirmed interstitial pneumonia) and mild group (30 patients). Basic cardiovascular autonomic reflex tests (CART) were performed, followed by beat-to-beat heart rate variability (HRV) and systolic and diastolic blood pressure variability (BPV) analysis, along with baroreceptor sensitivity (BRS). Non-linear analysis of HRV was provided by Poincare Plot. Results were compared to 77 sex and age-matched controls. RESULTS: AD (sympathetic, parasympathetic, or both) in our study has been revealed in 51.5% of severe, 78.0% of mild COVID-19 patients, and the difference compared to healthy controls was significant (p = 0.018). Orthostatic hypotension has been established in 33.0% COVID-19 patients compared to 2.6% controls (p = 0.001). Most of the spectral parameters of HRV and BPV confirmed AD, most prominent in the severe COVID-19 group. BRS was significantly lower in all patients (severe, mild, CADG), indicating significant sudden cardiac death risk. CONCLUSION: Cardiovascular autonomic neuropathy should be taken into account in COVID-19 patients' assessment. It can be an explanation for a variety of registered manifestations, enabling a comprehensive diagnostic approach and further treatment.

Identification and performance of multiple clinical and laboratorial risk factors for diagnosis of cardiac autonomic neuropathy in type 1 diabetes patients.

PURPOSE: The incidence of cardiac autonomic neuropathy (CAN) in patients with type 1 diabetes (T1D) is frequently underestimated. Individuals with T1D and CAN have an increased mortality risk, mainly from cardiovascular causes. The objectives of the present study were to assess the clinical and laboratory characteristics associated with CAN in patients with T1D and verify the ability of multiple clinical factors to help identify patients with this condition. METHODS: 102 patients with T1D were evaluated for CAN using standardized cardiovascular reflex testing. Clinical characteristics were used to compute a numerical score for CAN diagnosis and a ROC curve elaborated for assessment of the best cutoff to predict CAN. This score was then applied to the second sample of 120 patients. The sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: Prevalence of CAN was around 35% in the first sample of patients and just below 20% in the second sample. Hypertension, total cholesterol, triglycerides, postprandial sweating, diastolic blood pressure, abnormal right and left 10 g monofilament, retinopathy, and nephropathy were considered independent predictors of CAN. The CAN-score cut-off was 16.88. This yielded a sensitivity of 50%, specificity 73.8%, positive predictive value 22.9%, and negative predictive value 90.5%. CONCLUSION: The use of a subset of clinical and laboratory characteristics can be more accessible than the cardiac reflex tests and more accurate than a single isolated characteristic.

[Diagnosis of diabetic cardiac autonomic neuropathy]. / A diabeteses cardialis autonóm neuropathia diagnosztikája.

Cardiac autonomic neuropathy (CAN) is a common complication in type 1 and 2 diabetes and is defined as the impairment of autonomic control of the cardiovascular system. CAN is strongly associated with increased mortality, and in some studies with morbidity of vascular complications, such as stroke, coronary artery disease and myocardial infarction. At the early stages, CAN can be subclinical and it becomes clinically evident as the disease progresses. Subclinically, the disease is defined by cardiovascular reflex testing, which may have prognostic implications. Clinically, the impairment in autonomic function is associated with resting tachycardia, exercise intolerance, orthostatic hypotension, syncope, intraoperative cardiovascular instability, silent myocardial infarction and ischemia, and increased mortality. Although very common and serious, CAN is a frequently overlooked complication of diabetes. Because the progression of cardiovascular denervation is partly reversible or can be slowed down in the early stages of the disease, recent guidelines strongly recommend screening for CAN in patients with diabetes. In this review we summarize the diagnostic tools suggested in the screening for diabetic CAN. Orv Hetil. 2019; 160(35): 1366-1375.

Cardiac autonomic dysfunction in patients with gastroesophageal reflux disease.

AIM: To investigate autonomic nervous function in patients with a diagnosis of gastroesophageal reflux disease (GERD). METHODS: The investigation was performed on 29 patients (14 men), aged 18-80 years (51.14 ± 18.34), who were referred to our Neurocardiology Laboratory at the Clinical and Hospital Center "Bezanijska Kosa" with a diagnosis of GERD. One hundred sixteen healthy volunteers matched in age and sex with the examinees served as the control group. The study protocol included the evaluation of autonomic function and hemodynamic status, short-term heart rate variability (HRV) analysis, 24 h ambulatory ECG monitoring with long-term HRV analysis and 24 h ambulatory blood pressure monitoring. RESULTS: Pathologic results of cardiovascular reflex test were more common among patients with reflux compared to the control group. Severe autonomic dysfunction was detected in 44.4% of patients and in 7.9% of controls (P < 0.001). Parameters of short-term analysis of RR variability, which are the indicators of vagal activity, had lower values in patients with GERD than in the control group. Long-term HRV analysis of time-domain parameters indicated lower values in patients with reflux disease when compared to the control group. Power spectral analysis of long-term HRV revealed lower low- and high-frequency values. Detailed 24 h ambulatory blood pressure analysis showed significantly higher values of systolic blood pressure and pulse pressure in the reflux group than in the control group. CONCLUSION: Patients with GERD have distortion of sympathetic and parasympathetic components of the autonomic nervous system, but impaired parasympathetic function appears more congruent to GERD.