Effects of xylazine and adrenaline combinations: Preliminary clinical application for non-surgical protocols of nephrosplenic entrapment in horses

Background and Aim: The medical treatment of horses with nephrosplenic entrapment (NSE) of the large colon through administrating phenylephrine and rolling during general anesthesia was effective and less expensive than surgical treatment. However, the selection of drugs for non-surgical treatment of NSE is not a usual method for clinical practice. This study aimed to identify the effects of combined drugs on the cardiac and splenic response in horses and provide information on the NSE of the large colon for clinical application. Materials and Methods: Six healthy Thai native crossbred horses were enrolled in this study. Horses received two protocols with a withdrawal period of 14 days: Group 1 received xylazine (0.5 mg/kg IV) and adrenaline (1 mcg/kg IV), and Group 2 received xylazine (0.5 mg/kg IV) and adrenaline (3 mcg/kg IV). Heart rate (HR), HR variability (HRV), heart dimensions, and the splenic response of six horses were measured before the sedation, 30 and 60 min later, and 65, 70, 75, 80, 90, and 100 min after adrenaline administration. Doppler was used to obtain systolic blood pressure. Results: The HRV low-frequency and high-frequency power ratios decreased after using xylazine. Hypertension was observed after adrenaline administration. In this study, there were only minimal differences in the HR and respiratory rate between groups. However, overall cardiac and splenic parameters were statistically higher in Group 2. Conclusion: This study suggested that xylazine and three micrograms of adrenaline preserved the cardiac autonomic activity balance and were safe to use non-surgical applicability in horses.

Can Yoga Boost Access to the Bodily and Emotional Self? Changes in Heart Rate Variability and in Affective Evaluation Before, During and After a Single Session of Yoga Exercise With and Without Instructions of Controlled Breathing and Mindful Body Awareness in Young Healthy Women

Exercise is indispensable for a healthy lifestyle. Yoga exercise can have positive effects on well-being and on cardiac autonomic activity making it an ideal intervention for improving mind-body interactions and resilience to physical and mental stressors. Emotions trigger especially strong bodily and affective-cognitive responses because of their social relevance for the self and their biological relevance of mobilizing the organism for action. This study investigates whether changes in emotion processing related to self-other referential processing and changes in cardiac autonomic activity, reflected by heart rate variability (HRV), occur immediately after already a single session of yoga exercise when yoga postures are practiced with or without breathing- and mindful body awareness instructions. Women, all university students (N = 34, final sample: n = 30, n = 25 naïve to yoga practice) were randomly assigned to two experimental groups who performed the same yoga exercises with or without controlled breathing and mindfulness instructions. Emotional, self-other referential processing, awareness of bodily signals and HRV indicators were investigated before and after the exercise using standardized experimental tasks, standardized questionnaires, and mobile recording devices. Exercising for 30 minutes changed cardiac activity significantly. HRV measures showed adaptability of cardiac activity during the exercise as well as during the affective task post- to pre-exercise. Exercising with breathing instructions and mindful body awareness had no superior effects on cardiac, particularly parasympathetic activity, compared to practicing the same movements without such explicit instructions. Self-referential processing did not change; however, participants were faster and more accurate in their affective judgments of emotional stimuli [regardless of their reference (self/other)], and showed better awareness of bodily signals after compared to before the exercise session. The results support immediate, adaptive effects of yoga exercise on cardiac and affective-cognitive processing in an all-female healthy sample. Therefore, yoga exercise could be recommended as a physical activity for boosting cardiac and emotional resilience in this target group.

Emotional and cardiovascular health: the impact of depression on cardiac autonomic activity

Background The coexistence of depression and cardiovascular diseases is frequently accompanied by an increased risk of adverse outcomes. QTc, an indicator of ventricular depolarization and cardiac autonomic activity, has been proposed as a biomarker of this interplay. Purpose We aimed to investigate the possible association of depression with QTc interval. Methods Assessment of depressive symptoms was performed in 1637 participants of the cross-sectional Corinthia study with the Zung self-rating depression scale in those younger than 65 years of age (Group 1) and with the geriatric depression scale in elderly individuals (>65 years, Group 2). Moreover, electrocardiogram was performed and measurement of the QT interval was derived after correction for heart rate (QTc) using the Bazett's formula. Abnormal QTc was present when QTc duration exceeded 440 ms. Results Group 1 individuals classified as having depression had longer QTc duration (No depression: 389.3±27.0 ms vs. Depression: 401.1±32.9 ms, p<0.001) and percentage of abnormal QTc (No depression: 2.0% vs. Depression: 10.8%, p=0.001) (Figure 1, Panels A and B). Elderly individuals had similar values of QTc (No depression: 409.9±29.6 ms vs. Depression: 405.2±46.4 ms, p=0.37) and percentage of abnormal QTc (No depression: 13.2% vs. Depression: 12.3%, p=0.78) irrespective of depression status (Figure 1, Panels C and D). The presence of depression in Group 1 subjects was associated with an increased QTc- by 10.8 ms and with an approximately 7-fold higher prevalence of abnormal QTc duration, even after adjustment for confounders (). Such finding was not detected in elderly individuals (Figure 1, Panel F). Conclusion Depression might adversely affect ventricular repolarization especially in middle-aged subjects. These findings highlight the interrelationship between emotional and cardiovascular health and the role of depression as a cardiovascular risk factor. FUNDunding Acknowledgement Type of funding sources: None. Figure 1

Effects of Acute-Partial Sleep Deprivation on High-Intensity Exercise Performance and Cardiac Autonomic Activity in Healthy Adolescents

Performing high-intensity exercise (HIE) in the morning under sleep deprivation may harm the health benefits related to sufficient sleep and HIE. Therefore, the aim of this study was to explore the effects of acute-partial sleep deprivation on HIE performance and cardiac autonomic activity by monitoring heart rate variability (HRV) indices. Twenty-nine healthy male adolescents in college were recruited to perform a one-time HIE session on the treadmill (Bruce protocol) after ≥7 h of normal control sleep (control) and after ≤4 h of acute-partial sleep deprivation (SD). At the beginning of control and SD periods and after exercising under the two sleep conditions, heart rate (HR), standard deviation of normal to normal (SDNN), square root of the mean squared differences of successive NN intervals (RMSSD), normalized low frequency power (LFn), normalized high frequency power (HFn), number of pairs adjacent NN intervals differing by ≥50 ms in the entire recording count divided by the total number of all NN intervals (pNN50), and short axis and long axis value in Poincaré plot (SD1 and SD2) were measured at rest in an upright sitting position. The participants slept 7.63 ± 0.52 and 3.78 ± 0.69 h during control and SD periods, respectively (p < 0.001). Compared with the control participants, those suffering sleep deprivation experienced a significant decrease in exercise duration, RMSSD, HFn, SD1, and pNN50 as well as a significant increase in maximum heart rate during exercise (p < 0.05). SDNN, RMSSD, HFn, SD1, and pNN50 decreased significantly after exercise (p < 0.05 and 0.01 and 0.001, respectively). In summary, acute-partial sleep deprivation affected aerobic exercise performance the next morning and led to decreased cardiac vagus activity and cardiac autonomic dysfunction.

Cardiac autonomic modulation and anti-TPO antibodies in Subclinical Hypothyroidism – Does any correlation exit?

Background Heart rate variability (HRV) reflects the balance of activities of sympathetic and parasympathetic components of the autonomic nervous system. Anti-thyroid antibodies have long been associated with thyroid dysfunction and influence thyroid profile testing, the most common being anti-Thyroid Peroxidase (TPO) and anti-Thyroglobulin antibodies. Subclinical hypothyroidism (SCHypo) is characterized by elevated TSH with normal thyroid hormones.We hypothesized that autonomic function may be deranged in anti-TPO positive sub-clinical hypothyroid cases even before the onset of overt hypothyroidism. Objectives To investigate the association between anti-TPO antibodies (anti-TPOAb) positive SCHypo and sympathovagal imbalance (SVI). Methodology: The study was conducted on age and BMI matched subclinical hypothyroid patients (n = 52) and healthy controls (n = 20). Cardiac autonomic activity was assessed by short term HRV in the time (SDNN, RMSSD, pNN50) and frequency domain (LFms2, HFms2, LFnu, HFnu, TP and LF/HF ratio). Nonlinear geometric measures (SD1, SD2, SD1/SD2, TINN, HRV triangular index) were also evaluated. Biochemical evaluation of serum thyroid profile, anti-TPOAb was done in all the subjects. Results Decreased HRV was observed in anti-TPOAb positive group when compared to negative and control groups. Significant positive correlation of anti-TPOAb with TSH, LF nu, LF/HF and negative correlation with SDNN, RMSSD, pNN50, SD1, SD1/SD2, HFnu and TP of HRV was observed. Conclusion Anti-TPOAb positive SCHypo group exhibited modifications in HRV characterized by decreased parasympathetic modulation, as compared to controls. The findings were also suggestive of increased risk of autonomic dysfunction in TPOAb- positive patients than negative. Anti-TPO antibody was significantly correlated with TSH and SVI in SCHypo patients.

Sleep Indices and Cardiac Autonomic Activity Responses during an International Tournament in a Youth National Soccer Team

This study aimed to describe habitual sleep and nocturnal cardiac autonomic activity (CAA), and their relationship with training/match load in male youth soccer players during an international tournament. Eighteen elite male youth soccer players (aged 14.8 ± 0.3 years; mean ± SD) participated in the study. Sleep indices were measured using wrist actigraphy, and heart rate (HR) monitors were used to measure CAA during night-sleep throughout 5 consecutive days. Training and match loads were characterized using the session-rating of perceived exertion (s-RPE). During the five nights 8 to 17 players slept less than <8 h and only one to two players had a sleep efficiency <75%. Players’ sleep duration coefficient of variation (CV) ranged between 4 and 17%. Nocturnal heart rate variability (HRV) indices for the time-domain analyses ranged from 3.8 (95% confidence interval, 3.6; 4.0) to 4.1 ln[ms] (3.9; 4.3) and for the frequency-domain analyses ranged from 5.9 (5.6; 6.5) to 6.6 (6.3; 7.4). Time-domain HRV CV ranged from 3 to 10% and frequency-domain HRV ranged from 2 to 12%. A moderate within-subjects correlation was found between s-RPE and sleep duration [r = −0.41 (−0.62; −0.14); p = 0.003]. The present findings suggest that youth soccer players slept less than the recommended during the international tournament, and sleep duration was negatively associated with training/match load.