ABSTRACT
Autonomic dysfunction related to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is increasingly described in the literature. We report the case of a 30-year-old male with a background of asthma and migraine who experienced a second episode of SARS-CoV-2 infection characterized by mild respiratory symptoms. Twenty-four days after the symptom onset, he developed acute syncope. A tilt test revealed a neuromediated cardioinhibitory response with asystole (Vasovagal Syncope International Study VASIS type 2B). The temporal association between SARS-CoV-2 infection and syncope seems to indicate a probable causal relationship, which requires corroboration by future studies.
Disfunção autonômica relacionada à infecção por coronavírus-2 da síndrome respiratória aguda grave (SARS-CoV-2) vem sendo cada vez mais descrita na literatura. Relatamos o caso de um homem de 30 anos de idade, com histórico de asma e enxaqueca, que apresentou um segundo episódio de infecção por SARS-CoV-2 caracterizado por sintomas respiratórios leves. Vinte e quatro dias após o início dos sintomas, desenvolveu um quadro agudo de síncope. Um teste de inclinação revelou uma resposta cardioinibitória neuromediada com assistolia (Vasovagal Syncope International Study VASIS tipo 2B). A associação temporal entre infecção por SARS-CoV-2 e síncope parece indicar uma provável relação causal, a qual requer corroboração por estudos futuros.
ABSTRACT
Vasovagal syncope (VVS) is the most common type of syncope; the lone cardioinhibitory syncope represents only a small group of patients; however, the "cardioinhibitory component" is highly prevalent in reflex syncope and can be severe enough to produce asystole, lasting for a few seconds followed by a recovery to sinus beats. The environment in which syncope occurs can compromise life, and in-depth knowledge of the disease can prevent deaths and guide the appropriate management. The therapeutic cornerstone is general measures (increase water and salt) followed by pharmacologic therapy; for cardioinhibitory syncope, both treatments fail most of the time, and the next therapeutic option is pacemaker implantation. However, although the pacemaker causes a reduction in syncope, recurrence is high, and a one-time, effective, and safe intervention would be ideal. Cardioneuroablation (CNA) therapy has been proposed as a pacemaker alternative with these characteristics. CNA has shown a high reduction or even complete syncope elimination during 3 years of follow-up in some studies. Patients also reported prolonged prodromal periods, which allowed them enough time to abort the syncope. Invasive therapies like CNA require further extensive cohort studies, randomized clinical trials, and more substantial follow-up to evaluate adverse side effects. This review highlights syncope pathophysiology, dividing it into a central theory and a peripheral theory, the diagnosis explaining the head-up tilt test protocols, and treatments like CAN, representing it with figures for a simplified understanding.
Subject(s)
Pacemaker, Artificial , Syncope, Vasovagal , Cardiac Pacing, Artificial , Humans , Syncope , Syncope, Vasovagal/diagnosis , Syncope, Vasovagal/therapy , Tilt-Table TestABSTRACT
The most frequent cause of syncope is vasovagal reflex. It is associated with worse quality of life, depression, fatigue and physical injury. Recurrence of vasovagal syncope is an aggravating, reaching the rate of 69%. Initial step and pharmacological treatment may not work, especially in patients with recurrent syncope without prodrome. These patients can present cardioinhibitory response with asystole. Studies were designed to analyses the effectiveness of pacemaker for prevention of syncope. In this review, nonrandomized clinical trials, open-label randomized, double-blind randomized, placebo-controlled, and studies based on tilt test or Implantable Loop Recorder findings will be discussed.