People who had Covid-19, including light frames, tend to have the short and medium term imbalances in the cardiovascular system, needing to seek rehab treatment. This is what a study of 130 volunteers conducted at the Federal University of São Carlos (UFSCar) with the support of FAPESP.
According to data disclosed in the magazine Scientific Reports participants tested up to six weeks after the infection showed a drastic decrease in heart rate variability (VFC), ie, in the time variation between each heartbeat. Already those tested in the periods between two and six months or between seven and 12 months after the infection showed gradual improvements, but without reaching the level of the control group (composed of people not infected by SARS-COV-2).
The VFC is considered a good health indicator, as it signals the heart's ability to adapt to physiological demands. Thus, the lower the index, worse the adjustments of heart rate and adaptation to environmental stressors (situations of escape, anguish and fear) and physiological (systemic inflammation, characteristic of COVID-19, for example).
“This study reinforces the need for rehab programs even for people who had light covid-19 and were not hospitalized. Participants were an average of 40 years of age and some had risk factors for cardiovascular disease such as high cholesterol, smoking, diabetes, obesity and hypertension. Apparently COVID-19 has enhanced this cardiovascular imbalance and, consequently, increased the risk of disease, ”says Audrey Borghi Silva, coordinator of the Cardiopulmonary Physiotherapy Laboratory (LACAP) of the Federal University of São Carlos (UFSCar).
The impact of COVID-19 on cardiac autonomic control has been demonstrated in several studies. “Our research contributes to confirmation of this impact and demonstrates that it can also happen in young or middle-aged individuals who had light covid-19 and did not need to be hospitalized,” says Aldair Darlan Santos-Dea, a UFSCar researcher and first author of the article.
Mismatch
In addition to lower heart rate variability, the researchers observed in volunteers infected with SARS-COV-2 a predominance of the sympathetic nervous system over the parasympathetic. These are the two faces of the autonomic nervous system, which controls the involuntary functions of the body, such as blood pressure and body temperature. While the parasympathetic system, among other tasks, makes the heart slow down when necessary, it is up to the sympathetic to increase heart rate in situations that involve danger and fear, for example.
“Good cardiovascular functioning requires a balance between these two mechanisms and, what we observe, is that the negative impact of Covid-19 infection in these individuals has caused a breakdown on the autonomic nervous system,” says Santos-De Araújo. “The observed pattern – of reduced heart rate variability and predominance of the sympathetic nervous system [ou redução da atividade parassimpática] – Indicates not only a decrease in global autonomic modulation, but also suggests a greater likelihood of unfavorable cardiovascular outcomes. ”
In addition, researchers highlight, the results infers a possible phase of transition from cardiac autonomic recovery, as individuals evaluated in the group with longer recovery since diagnosis had better behavior of this sympathetic-parassimatic balance.
“This transient effect can be observed more clearly in the earlier group [até seis semanas após a infecção]which presented worse heart rate variability, progressively improving over time, however, not reaching the levels observed in the group of non-infected participants, ”explains Santos-de Araújo.
The study also showed that dyspnea (shortness of breath) was the most common symptom among individuals with worst cardiac autonomic modulation, but was not the only one. “In the group of individuals monitored in the closest period of the infection we observed a higher percentage of cough [47%]fatigue [50%]headache [56%]ageusia [perda do paladar, 53%]anxiety [62%]running [50%] and greater prevalence of non -vaccinated individuals [44%]”, Says Santos-of-Araújo.
This content was originally published in the light form of COVID-19 tends to cause cardiovascular imbalance on the CNN Brazil website.
Source: CNN Brasil