Heart Rate Variability Indices as Possible Biomarkers for the Severity of Post-traumatic Stress Disorder Following Pregnancy Loss

Background: Psychological distress, such as posttraumatic stress disorder (PTSD), is commonly evaluated using subjective questionnaires, a method prone to self-report bias. The study's working hypothesis was that levels of autonomic dysfunction determined by heart rate variability (HRV) measures are associated with the severity of PTSD in women following pregnancy loss.Methods: This was an observational prospective cohort study with 53 patients enrolled. The DSM-5 (Diagnostic and Statistical Manual of Mental Disorders) PTSD scale (PCL-5) was used to assess the severity of PTSD in women after pregnancy loss. The cardiac autonomic function was assessed using HRV measurements during a deep breathing test using an HRV scanner system with wireless ECG enabling real-time data analysis and visualization. HRV measures were: standard deviation (SD) of normal R-R wave intervals [SDNN, ms], square root of the mean of the sum of the squares of differences between adjacent normal R wave intervals [RMSSD, ms], and the number of all R-R intervals in which the change in consecutive normal sinus intervals exceeds 50 milliseconds divided by the total number of R-R intervals measured [pNN50 = (NN50/n-1)*100%] [pNN50%].Results: The PCL-5 scores had a statistically significant association with HRV indices (SDNN; RMSSD, and pNN50%). Patients with PTSD had similar mean heart rate values as compared to patients without PTSD (PCL-5), but significantly higher SDNN [median[IQR, interquartile range]: 90.1 (69.1–112.1) vs. 52.5 (36.8–65.6)], RMSSD [59.4 (37.5–74.9) vs. 31.9 (19.3 – 44.0)], and PNN50% values [25.7 (16.4–37.7) vs. 10.6 (1.5–21.9)]. The SDNN of the deep breathing test HRV was effective at distinguishing between patients with PTSD and those without, with an AUC = 0.83 +/− 0.06 (95 % CI 0.94, p = 0.0001) of the ROC model.Conclusions: In this study, HRV indices as biomarkers of cardiac dysautonomia were found to be significantly related to the severity of PTSD symptoms in women after pregnancy loss.

Cardiac autonomic neuropathy in fibromyalgia: Revisited

BACKGROUND: Fibromyalgia (FM) is associated with widespread autonomic dysfunction where sympathetic predominance explains associated complaints such as widespread pain, sleep disorders and anxiety. Recent studies indicate a possible neurovascular autonomic interaction in the pathogenesis of FM. OBJECTIVE: Our study paradigm included a modified Ewing’s battery of autonomic function tests to find the cardiac autonomic neuropathy (CAN) in FM patients. The battery comprises some tests such as the Valsalva maneuver, which are effort-dependent, so we also aimed to identify a potential simplified test out of the whole battery as an index marker of CAN in FM patients. METHODS: Forty-two female patients with FM were included in this study and were administered sympathetic and parasympathetic reactivity tests to explore the presence of CAN. We compared the results from each sympathetic and parasympathetic reactivity test against CAN. RESULTS: Delta heart rate in the deep breathing test was significantly different in patients with and without CAN. Delta heart rate also exhibited best diagnostic performance (AUC = 0.769, 95% CI: 0.619–0.920, p< 0.001), with 88% sensitivity, 64% specificity, and 89% negative predictive value (NPV). The 30: 15 ratio during the lying to standing test also emerged as a suitable index; however it did not show any difference between CAN and non-CAN patients. CONCLUSION: The delta heart rate has the best diagnostic accuracy, primarily in CAN’s exclusion by its very high sensitivity and NPV.

The effect of deep breathing test on heart rate variability in obese and non-obese patients with myocardial infarction

Introduction and Aim:Obesity and metabolic syndrome increases the risk of cardiovascular diseases (CVD).The acute myocardial infarction may be associated with autonomic dysfunction and it may have a bearing on the prognosis. The objective of the study wasto examine the effect of deep breathing test on heart rate variability in obese and non-obese patients with myocardial infarction (MI). Materials and Methods:The patients with acute myocardial infarction were confirmed by universal definition and treatment was administered. At 12 weeks of follow up, the MI patients were screened and divided into two groups. 30 patients of MI with BMI 25 to 30 kg/m2 formed the obese group.30 patients of MI with BMI 18.5 to 24.9 kg/m2 formed the non-obese group. The baseline ECG was taken for 5 minutes by using Niviqure B3 machine for HRV analysis. Then, deep breathing test (DBT) was performed in a standardized manner. Results:The two groupswere well matched for the age (53.7±11.5 vs.55.2±9.2years).In the baseline there was a statistically significant decrease in the total power (TP) of the heart i.e., HF plus LF (2178±762ms2 vs2991±771ms2 with a ‘p’ value 0.001) in the obese group when compared to non-obese group. On DBT there was a significant decrease in heart rate (81bpm to 65bpm) in non-obese group. However, in obese group there was no significant decrease in heart rate (79bpm to 72bpm) on DBT. Conclusion: Accordingly, we concludethat in obese patients with MI there is a reduction in respiratory vagal modulation of heart rate during DBT.

Features of heart rate variability in patients with takotsubo syndrome

Funding Acknowledgements Type of funding sources: None. Main funding source(s): North-Western State Medical University named after I.I. Mechnikov Objective to study the features of autonomic regulation of sinus rhythm features of autonomic regulation of cardiac sinus rhythm in patients with Takotsubo syndrome (TTS) during inpatient stay in hospital. Materials and methods. The study included 25 female patients (the median age 57.5 ± 28.5 years) with TTS, diagnosis was based on the InterTAK criteria. On the 5-7th day after admission, the heart rate variability (HRV) was assessed both at rest and cardiac autonomic function tests: the deep breathing test (DBT) and active orthostatic test (AOT) with the usage of a computer diagnostic system «Valenta». RESULTS According to HRV data, initially at rest, the majority of the studied patients predominantly had a parasympathetic impact on the heart rate regulation: in 70% - increased parasympathetic influence, in 17% - increased sympathetic influence, in 13% - a balanced heart rate regulation. When performing a DBT, the predominance of the parasympathetic influence on the heart rate was noted both in spectral parameters and according to the data of time analysis (HF during DBT increased 1.8 times up to 489.6 ± 114.2 ms2 (p &lt;0.05) ; LF decreased 1.7 times up to 254.1 ± 70.3 ms2 (p &lt;0.05); VLF increased 2.8 times up to 402.3 ± 101.8 ms2 (p &lt;0, 05); TP increased 1.4 times up to 1145.9 ± 251.3 ms2; CV increased 1.3 times up to 6.5 ± 0.7% (p &lt;0.05); SDNN increased 1.3 times up to - 58.7 ± 6.6 ms (p &lt;0.05). HRV measured during an AOT showed a paradoxical evaluation in the parasympathetic impact on the heart rate (HF increased by 1.8 times and reached - 488.0 ± 104.7 ms2 (p &lt;0.05); LF decreased by 1.1 times up to 408 , 4 ± 103.6 ms2; VLF increased 1.2 times up to 166.4 ± 52.2 ms2; TP increased 1.3 times up to 1062.8 ± 181.1 ms2 (p &lt;0.05); CV increased 1.6 times up to 8.0 ± 0.9% (p &lt;0.05); SDNN increased 1.4 times up to 62.6 ± 7.5 ms (p &lt;0.05)). Conclusions During the index hospital inpatient stays the majority of patients with TTS have a vegetative imbalance due to increased parasympathetic influence on the heart rate, both at rest and during a deep breathing test and an active orthostatic test. This fact is quite unexpected and requires further study.

Assessment of Functions of the Autonomic Nervous System in the Elderly with Different Comorbid Factors

Background Studies in healthy elderly patients have shown the prevalence of autonomic dysfunction (AD) in the range of 20 to 30%. However, there is paucity in data pertaining to AD in the elderly in the Indian context. Objective To assess the prevalence of AD in the elderly irrespective of their comorbidity status. Methods A total of 141 elderly patients with or without comorbidities/symptoms of AD were included. Demographic and clinical details of the patients were recorded. Autonomic function tests (AFTs) such as deep breathing test, Valsalva ratio, orthostatic heart rate (OHR), isometric handgrip test, and orthostatic blood pressure were performed based on Ewing’s battery of tests. The sensitivity, specificity, positive predictive value, negative predictive value, and the accuracy of AFTs were evaluated. Results Most patients (n = 85) were aged between 60 and 69 years, with a male predominance (58.87%). Hypertension and diabetes mellitus were the most common comorbidities. Postural hypotension was the most common symptom of AD. With advancing age, symptoms of AD manifested significantly more. Overall, 73.8% of patients had AD, of whom 45.4% had early AD. Number of AD symptoms, glycated hemoglobin (HbA1c) level, and comorbid factors (diabetes and hypertension) were significantly associated with the results of AFTs (p < 0.05). AFTs were highly significant with respect to the results obtained (p < 0.001). Deep breathing test, abnormal in majority of study patients, has a sensitivity of 93.3% and OHR has a specificity of 81.1% to determine AD. Conclusion The study concludes that age itself is an independent predictor of AD, which increases in severity if associated with comorbidities.

Hypothyroidism syndrome as a risk factor for parasympathetic innervation disorders

The objective: to study the significance of the presence of hypothyroidism syndrome as a risk factor for the development of autonomic neuropathy (AN). Materials and methods. The study involved 77 women, of whom 31 had hypothyroidism syndrome, and 46 had euthyroid thyroid pathology. The age of patients with hypothyroidism syndrome ranged from 24 to 57 years and averaged 42.4±9.20 years, mean age patients of the euthyroid pathology group of the thyroid gland was equal to 40.0±12.22 years (age interval 20–63 years). Patients underwent an ultrasound examination of the thyroid gland, fasting glycemia levels, A1c, TSH, T4s, T3s, blood creatinine levels, and GFR were calculated using CKD-EPI on line equations. In addition, antithyroglobulin and antithyroperoxidase levels were determined. To diagnose autonomic neuropathy, a Valsalva test and a deep breathing test were used. Statistical analysis was performed using the standard computer program Microsoft Excel. Results. The state of autonomous innervation was normal in 71.0% of the examined hypothyroidism group and in 97.8% of the euthyroidism group. AN was absent both in hypothyroidism syndrome (0.0%) and in euthyroid thyroid pathology (0.0%). Moreover, the “borderline state” of autonomic innervation was observed in 29.0% of the examined groups of hypothyroidism syndrome and only 2.2% of the examined groups of thyroid euthyroid pathology (p=0.0019). The chance of finding parasympathetic disorders in the hypothyroidism group was 0.409, and in the group of euthyroid thyroid pathology was 0.022. Conclusions. Thus, in the presence of hypothyroidism, the chances of finding autonomic disorders were 18.409 times higher than those for euthyroid thyroid pathology, which requires appropriate correction when planning comprehensive treatment tactics. Key words: autonomic neuropathy, hypothyroidism syndrome, euthyroid pathology of the thyroid gland.

Utility of autonomic testing for the efficient diagnosis and effective pharmacological management of neurogenic orthostatic hypotension

A 62-year-old man presented with a 2-year history of syncope, collapse and fluctuating blood pressure (BP). His medications included midodrine (10 mg, three times per day) and fludrocortisone (0.1 mg, two times per day), but neither treatment afforded symptomatic relief. Autonomic testing was performed. Head-up tilt table testing revealed a supine BP of 112/68 mm Hg (heart rate, 74 beats per minute (bpm)) after 6 min, which dropped to 76/60 mm Hg (83 bpm) within 2 min of 80° head-up tilt. Findings from a heart rate with deep breathing test and a Valsalva test were consistent with autonomic dysfunction. The patient was diagnosed with neurogenic orthostatic hypotension and treated with droxidopa (100 mg, two times per day; titrated to 100 mg, one time per day). After initiating treatment with droxidopa, the patient no longer reported losing consciousness on standing and experienced improvement in activities of daily living. These improvements were maintained through 1 year of follow-up.

Autonomic Influence on Heart Rate for Deep Breathing and Valsalva Maneuver in Healthy Subjects

Introduction: The Autonomic nervous system is responsible for regulation and integration of visceral functions. Disturbance of autonomic nervous system play crucial role in pathogenesis and clinical course of many diseases. In the present study deep breathing test and valsalva maneuver have been described to monitor parasympathetic function genderwise. Methods: A cross-sectional study was conducted among 100 subjects, aged 18-25 years, from May to November 2017, in exercise physiology laboratory, Kathmandu University School of Medical Sciences, Chaukot, Kavre. Electrocardiograph recorded by AD instrument was used to calculate the resting heart rate and the heart rate response to deep breathing test and valsalva maneuver. Results: Heart rate response to deep breathing test (31.69±14.79 Vs. 36.08±18.65, P=0.195) and valsalva ratio (1.59±0.39 Vs. 1.69±0.54, P=0.314) tend to be higher in female than male subjects but not significant. The resting heart rate of females was significantly higher than that of males (84.37 ± 11.08 Vs. 78.43 ± 12.06, P<0.05). Heart rate was significantly increased during and decreased after valsalva maneuver in both male and female subjects. Conclusions: This study concludes that both deep breathing test and valsalva maneuver activates parasympathetic system inhealthy subjects. And also dominant parasympathetic activity was found in female comparison to male subjects.