Heart Rate Variability (HRV) and arterial pressure (AP) variability and their responses to head-up tilt test (HUTT) were investigated in Post-COVID-19 syndrome (PCS) patients reporting tachycardia and/or postural hypotension. Besides tachycardia, PCS patients also showed attenuation of the following HRV parameters: RMSSD [square root of the mean of the sum of the squares of differences between adjacent normal-to-normal (NN) intervals] from statistical measures; the power of RR (beat-to-beat interval) spectra at HF (high frequency) from the linear method spectral analysis; occurrence of 2UV (two unlike variation) pattern of RR from the nonlinear method symbolic analysis; and the new family of statistics named sample entropy, when compared to control subjects. Basal AP and LF (low frequency) power of systolic AP were similar between PCS patients and control subjects, while 0 V (zero variation) patterns of AP from the nonlinear method symbolic analysis were exacerbated in PCS patients. Despite tachycardia and a decrease in RMSSD, no parameter of HRV changed during HUTT in PCS patients compared to control subjects. PCS patients reassessed after 6 months showed higher HF power of RR spectra and a higher percentage of 2UV pattern of RR. Moreover, the reassessed PCS patients showed a lower occurrence of 0 V patterns of AP, while the HUTT elicited HR (heart rate) and AP responses identical to control subjects. The HRV and AP variability suggest an autonomic dysfunction with sympathetic predominance in PCS patients. In contrast, the lack of responses of HRV and AP variability indices during HUTT indicates a marked impairment of autonomic control. Of note, the reassessment of PCS patients showed that the noxious effect of COVID-19 on autonomic control tended to fade over time. 

pdf/investigating-autonomic-nervous-system-dysfunction-among-41wmhbdtl3.pdf

Investigating autonomic nervous system dysfunction among patients with post-COVID condition and prolonged cardiovascular symptoms

BACKGROUND
It is unclear whether muscle blood flow (MBF) is altered in long-term Hodgkin Lymphoma (HL) survivors. We test the hypothesis that: 1) MBF response during mental stress (MS) is impaired in long-term HL survivors; 2) Aerobic exercise training combined with local strength exercise (ET) restores MBF responses during MS in these survivors.


METHODS
Eighteen 5-year HL survivors and 10 aged-paired healthy subjects (HC) were studied. Twenty HL survivors were randomly divided into two groups: Exercise-trained (HLT, n=10) and untrained (HLUT, n=10). Maximal aerobic capacity was evaluated by a cardiopulmonary exercise test and forearm blood flow (FBF) by venous occlusion plethysmography. MS was elicited by Stroop Color Word Test. ET was conducted for four months, three/week for 60 minutes each session. The aerobic exercise intensity corresponded to anaerobic threshold up to 10% below the respiratory compensation point. The strength exercises consisted of 2-3 sets of chest press, pulley and squat exercises, 12-15 repetitions each exercise at 30-50% of the maximal voluntary contraction.


RESULTS
Baseline was similar in HL survivors and HC, except peak oxygen consumption (peak VO2, p=0.013) and FBF (p=0.006) that were lower in the HL survivors. FBF responses during MS were lower in HL survivors (p<0.001). ET increased peak VO2 (11.59±3.07%, p=0.002), and FBF at rest (33.74±5.13%, p<0.001) and during MS (24±5.31%, p=0.001). Further analysis showed correlation between the changes in peak VO2 and the changes in FBF during MS (r=0.711, p=0.001).


CONCLUSION
Long-term HL survivors have impaired MBF responses during MS. ET restores MBF responses during MS.

Aerobic Exercise Training Combined with Local Strength Exercise Restores Muscle Blood Flow and Maximal Aerobic Capacity in Long-Term Hodgkin Lymphoma Survivors.

Evaluation of myocardial work and exercise capacity in patients recovered from the severe form of covid-19

Post-acute Sequelae of SARS-CoV-2 infection (PASC) often leads to exertional intolerance and reduced exercise capacity, particularly in individuals previously admitted to an intensive care unit (ICU). However, the impact of invasive mechanical ventilation (IMV) on PASC-associated cardiorespiratory abnormalities during exercise remains poorly understood. This single-center, cross-sectional study aimed to gather knowledge on this topic. Fifty-two patients with PASC recruited ~6 months after ICU discharge were clustered based on their need for IMV (PASC+IMV, n=27) or non-invasive support therapy (PASC+NIS, n=25). Patients underwent pulmonary function and cardiopulmonary exercise testing (CPX), and were compared to a reference group (CONTROL, n=19) comprising individuals of both sexes with similar age, comorbidities, and physical activity levels, but without a history of COVID-19 illness. Individuals with PASC, irrespective of support therapy, presented with higher rates of cardiorespiratory abnormalities than CONTROL, especially dysfunctional breathing patterns, dynamic hyperinflation, reduced oxygen uptake and oxygen pulse, and blunted heart rate recovery (all P<0.05). Only the rate of abnormal oxygen pulse was greater among PASC+IMV than PASC+NIS (P=0.05). Mean estimates for all CPX variables were comparable between PASC-IMV and PASC-NIS (all P>0.05). These findings indicate significant involvement of both central and peripheral factors, leading to exertional intolerance in individuals with PASC previously admitted to the ICU, regardless of their need for IMV.

Cardiorespiratory abnormalities in ICU survivors of COVID-19 with Post-acute Sequelae of SARS-CoV-2 infection are unrelated to invasive mechanical ventilation.

Background: Numerous research studies have unveiled the significant impacts of neurofeedback (NFB) on individuals suffering from depression, anxiety, and stress. Objectives: In light of these findings, the current trial aimed to assess the efficacy of neurofeedback in alleviating stress symptoms among students experiencing high levels of stress, utilizing the neurofeedback method. Methods: The trial comprised 30 students aged between 15 and 25 years old who were identified as experiencing psychological distress. To ensure an in-depth investigation and account for potential confounding variables, we employed a randomized controlled trial design, randomly allocating participants to either the experimental or control group. The first group received an 8-week course of neurofeedback treatment, while the control group did not receive any specific treatment but underwent psychological assessments at predetermined intervals. Baseline measurements were taken at the commencement of the study, utilizing the Depression Anxiety Stress Scales (DASS-21) and salivary tests. Subsequent measurements were conducted after 4 weeks and at the conclusion of the research. The collected data underwent repeated measures of variance analysis for statistical evaluation. Results: At the conclusion, the mean of the experimental group (36.8) and control group (76.67) were found to be significantly different (P < 0.001). Furthermore, after 4 weeks into the study, the repeated measures variance analysis revealed that the mean of the experimental group was lower than that of the other group (P < 0.05, ES: 0.651). Conclusions: The results of this trial suggest that neurofeedback (NFB) can be considered an effective, low-risk, non-invasive treatment option for individuals experiencing high levels of stress, as indicated by the significant reduction in salivary biomarkers.

Effectiveness of Neurofeedback on Psychological Stress, Salivary Cortisol and α-amylase Level in Students: A Randomized and Parallel-Group Clinical Trial

INTRODUCTION
Previous studies show that COVID-19 survivors have elevated muscle sympathetic nerve activity (MSNA), endothelial dysfunction, and aortic stiffening. However, the neurovascular responses to mental stress and exercise are still unexplored. We hypothesized that COVID-19 survivors compared with age- and body mass index (BMI)-matched healthy controls exhibit abnormal neurovascular responses to mental stress and physical exercise.


METHODS
Fifteen severe COVID-19 survivors (aged: 49±2 years, BMI: 30±1 kg/m2) and 15 well-matched control subjects (aged: 46±3 years, BMI: 29±1 kg/m2) were studied. MSNA (microneurography), forearm blood flow (FBF), and forearm vascular conductance (FVC, venous occlusion plethysmography), mean arterial pressure (MAP, Finometer), and heart rate (HR, EKG) were measured during a 3-minutes mental stress (Stroop color word test) and during a 3-minutes isometric handgrip exercise (30% of maximal voluntary contraction).


RESULTS
During mental stress, MSNA (frequency and incidence) responses were higher in COVID-19 survivors than in controls (P<0.001), and FBF and FVC responses were attenuated (P<0.05). MAP was similar between the groups (P>0.05). In contrast, the MSNA (frequency and incidence), and FBF and FVC responses to handgrip exercise were similar between the groups (P>0.05). MAP was lower in COVID-19 survivors (P<0.05).


CONCLUSION
COVID-19 survivors exhibit an exaggerated MSNA and blunted vasodilatory response to mental challenge compared to healthy adults. However, the neurovascular response to handgrip exercise is preserved in COVID-19 survivors. Overall, the abnormal neurovascular control in response to mental stress suggests that COVID-19 survivors may have an increased risk to cardiovascular events during mental challenge.

Neurovascular and Hemodynamic Responses to Mental Stress and Exercise in Severe COVID-19 Survivors.


 
 
 The illicit use of anabolic androgenic steroids (AAS) has been associated with diminished cholesterol efflux mediated by HDL, remarkable decrease in high-density lipoprotein (HDL) plasma concentration and subclinical coronary artery disease (CAD). Inflammation is the key to the atherogenic process associated with atherosclerotic plaque vulnerability. The pericoronary mean fat attenuation (pFAM) has emerged as a marker of coronary inflammation and can predict future cardiovascular events, which is measurable from standard coronary computed tomography angiography (CCTA). However, whether AAS abuse has a role in pFAM in young male AAS users is unknown.
 
 
 
 The aim of this study was to evaluate whether AAS abuse could leads to higher pFAM and premature coronary inflammation in young male AAS users.
 
 
 
 Twenty strength-trained AAS users (AASU) age 29±5 yr, 20 age-matched strength-trained AAS nonusers (AASNU), and 10 sedentary controls (SC) were enrolled in this study. Coronary inflammation was assessed by pFAM-CCTA in the right coronary artery (RCA), left anterior descending artery (LDA) and left circumflex coronary artery (Cx).
 
 
 
 pFAM in the RCA was significantly higher in AASU compared with AASNU and SC (−64.59±9.45 vs. −79.21±6.67 vs. −80.97±7,91 Hounsfield Units (HU), respectively, p<0.001]. Also, the pFAM in the LAD was higher in AASU compared with AASNU and SC (−72.83±7.21 vs. −79.41±6.72 vs. −80.97±7.72 HU, p=0.006). However, no difference to pFAM in the Cx between AASU, AASNU and SC (−74.30±5.85 vs. −79.77±7.13 vs. −78.19±5.82 HU, respectively, p=0.069) was found.
 
 
 
 This study indicates that AAS abuse may be associated with higher pFAM and premature coronary inflammation in the RCA and LAD. The higher pFAM may be linked to early development of CAD in young AAS users.
 
 
 
 Type of funding sources: Other. Main funding source(s): Fundação Zerbini


/pdf/coronary-inflammation-by-computed-tomography-pericoronary-1v0tadwt.pdf

Coronary inflammation by computed tomography pericoronary fat attenuation in young male anabolic androgenic steroid users

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Neurovascular and Hemodynamic Responses to Mental Stress and Exercise in Severe COVID-19 Survivors.

Coronary inflammation by computed tomography pericoronary fat attenuation in young male anabolic androgenic steroid users