ABSTRACT
The uncontrolled hyper-inflammation in critically ill patients with COVID-19 might be associated with a dysfunction of the cardiovascular regulatory mechanisms. In order to estimate the involvement of cardiovascular control in limiting the risk of mortality in COVID-19 patients we assessed the degree of asynchrony between heart period (HP) and systolic arterial pressure (SAP) variability at rest in supine condition (REST) and during an orthostatic challenge, namely the modified head-up tilt (MHUT), in 18 COVID-19 patients (age: 62± 10 yrs, 15 men) admitted in intensive care unit (ICU) for pneumonia. The patients were distinguished in two groups, i.e. survivors (SURVs) or non survivors (noSURVs) according to the outcome. Asynchrony between HP and SAP was assessed via a model-free nonlinear marker in the information domain, i.e. cross-sample entropy (CSampEn). Neither demographic indexes nor time domain markers could separate the two groups and this result held regardless of the experimental condition. Conversely, CSampEn could and, more precisely, noSURVs subjects had a significantly larger HP-SAP asynchrony when compared to SURVs in response to MHUT. We conclude that measures of the derangement of the cardiovascular control might be helpful to stratify the risk of mortality in COVID-19 critically ill patients. © 2022 Creative Commons.
ABSTRACT
Some aspects of cardiorespiratory coupling (CRC) require tools capable of accounting for nonlinearities. Joint symbolic analysis (JSA) has been proposed to characterize CRC via the rate of short, jointly coordinated (C), patterns obtained from the heart period (HP) variability and respiration (R) series. C schemes were distinguished according to the dominant time scale governing CRC. We applied JSA to a database of 19 healthy subjects (age: 27-35 yrs, median = 31 yrs;8 males) during spontaneous and paced breathing at varying respiratory rates. The rate of C pattern did not vary with the breathing rate, but the proportions of C pattern families changed with respiratory frequency. We conclude that JSA is a useful tool to investigate the effect of breathing patterns on CRC, with potential applications in patients with respiratory failure such as that developed in COVID-19 syndrome.
ABSTRACT
The COVID-19 pandemic significantly changed the working settings of millions of office employees. Recently, the study of the cardiac autonomic control profile (CACP) has been suggested as an early screening tool in occupational medicine. In this study we describe the CACP in relation to different working conditions. Seventeen healthy office active employees (age: 38 +/- 7 yrs, 9/8 males/females) were studied, by means of electrocardiogram 24-hour Holter monitoring, while alternating working at home (SMART) and in the office (OFFICE), respectively. The beat-to-beat series of the time distance between two consecutive R-wave peaks was extracted during the 24 hours. Parametric power spectral analysis was iterated over the RR series during daytime (DAY) and nighttime (NIGHT). The degree of perceived stress, as measured via the visual analogue scale, was higher in OFFICE. During NIGHT the variance of the RR series was higher in SMART than in OFFICE situation. A similar tendency was observed for the absolute power of RR series in high frequency band. We conclude that the expected circadian rhythm of the vagal control is more evident in the SMART situation than in the OFFICE condition and the perceived stress is lower, with beneficial effects for the cardiovascular system and for the overall status of the entire organism.
ABSTRACT
Respiratory and cardiac activities are known to be linked by several mechanisms, resulting in a variety of patterns of heart rate variability. Cardiorespiratory interactions can be evaluated from spontaneous variability of heart period (HP) and respiration (R) through noncausal and causal approaches. The aim of this study is to describe cardiorespiratory interactions in a population known to feature an exaggerated sympathetic response to orthostatic stressors, such as patients affected by postural orthostatic tachycardia syndrome (POTS). Twelve female POTS patients (age: 36 +/- 10 yrs) and 14 female healthy controls (age: 37 +/- 8 yrs) underwent electrocardiogram and respiratory movement recordings while supine and during head-up tilt. Cardiorespiratory interactions were assessed via a model-based noncausal approach, squared coherence (K-2), and a model- based causal method, transfer entropy (TE). TE was found to be significantly decreased in POTS patients compared to healthy controls during head-up tilt, while K-2 was similar. We conclude that causal approaches are better suited than noncausal methods to evaluate modifications in the magnitude of HPR variability interactions in POTS patients during orthostatic challenge, with possible future applications in post-acute COVID-19 patients exhibiting symptoms of dysautonomia.
ABSTRACT
Background: The COVID-19 pandemic led to the implementation of massive lockdown measures producing a reduction in consultations, diagnostic tests, treatments and admissions for cardiovascular and cerebrovascular events and cancer. Objective: The aim of this study was to determine the access to medical care and health care information in patients with cardiovascular diseases during social, preventive, and mandatory confinement in Argentina. Results: A total of 1,487 surveys were analyzed. Mean age was 56.17 ± 14.0 years;66.8% of survey respondents were women, 38.9% lived in the Greater Buenos Aires area and 27.1 % in the Autonomous City of Buenos Aires. The most commonly reported main cardiovascular disease was hypertension (52.1%);42% required medical care and 57.9% could not access to consultation due to issues related with the health system in 68.2% of cases. Only 16.4% did not request medical care for fear of becoming infected with COVID-19. Seventy-two percent required prescriptions and 13% did not obtain them. Access to vaccination was normal in 41.4% of respondents. Social mandatory isolation was respected in 92.4% of cases. Finally, 54.6% of the surveyed population felt unprotected by the health system. Conclusions: We believe that access of the population with chronic cardiovascular diseases to the health system should be warranted in order to adapt monitoring and minimize hospitalization due to decompensation in this high-risk population.