Autonomic Dysfunction after Covid-19 Immunization - Case Report

Background: The infection caused by the SARS-CoV-2 continues affecting millions of people worldwide and vaccines to prevent the coronavirus disease (COVID-19) are considered the most promising approach for curbing the pandemic. Otherwise, cardiovascular and neurological complications associated with the vaccines were speculated and some few case reports were published. Objective(s): We describe a case of postural orthostatic tachycardia syndrome (POTS) after viral vector COVID-19 vaccination and the possible autoimmune process of the syndrome. Method(s): A 35-year-old female, without previous symptoms or comorbidities, developed intermittent palpitation, intense fatigue and dyspnea, compromising her daily activities, triggered by upright position, seven days following the second dose of the Oxford vaccine. Physical examination was normal, except for a heart rate (HR) increase of 33 beats/min from supine to standing position, with no significant change in blood pressure and reproduction of symptoms. Result(s): A 24-hour Holter monitoring revealed episodes of spontaneous sinus tachycardia correlated with palpitation and fatigue. Extensive diagnostic investigations excluded primary cardiac, endocrine, infectious and rheumatologic etiologies. The patient underwent an autonomic function test which demonstrated normal baroreflex sensitivity, as well as normal cardiovagal and adrenergic scores. Head-up tilt test showed persistent orthostatic tachycardia (HR increase from a medium of 84 beats/min in supine position to 126 beats/min during upright tilt), without hypotension, consistent with the diagnostic criteria for POTS. According to the current guidelines, general behavior recommendations, pharmacotherapy with low dose of propranolol associated with the autonomic rehabilitation were oriented. Along three months of follow-up, the patient reported a gradually improvement in her symptoms. Conclusion(s): POTS is a heterogeneous disorder of the autonomic nervous system characterized by orthostatic tachycardia associated with symptoms of orthostatic intolerance. Although the physiopathology of COVID-19 vaccine and autonomic disorders remains speculative, autoimmune response is one of the possible mechanisms. Based on clinic presentation, the time frame of symptom onset is consistent with other well-known post-vaccination syndromes, which may be an indicator of an autoimmune process induced by immunization. Further studies are needed to assess causal relationship between immunization and autonomic dysfunction.Copyright © 2023

Stereotactic Radiotherapy for the Treatment of Recurrent Refractory Vt in Chagas Disease Patients

Background: Stereotactic radiotherapy (SBRT) is a new therapeutic option for patients with scar related ventricular tachycardia (VT). Objective(s): To describe our experience with the use of SBRT for the treatment of recurrent VT in patients with Chagas Cardiomyopathy (CCM) in whom catheter ablation is not an option. Method(s): We selected patients with Chagas Disease that underwent SBRT for recurrent VT treatment. The target sites of SBRT were planned based on CMR and CT reconstruction on ADAS software, bipolar voltage maps from previous CA procedures and VT morphology induced on a electrophysiologic study performed SBRT planning. Target sites were decided together by electrophysiology and radiation oncology group. Result(s): We performed SBRT in six CCM patients July 2021 to July 2022. Most patients were male (66.7%), mean age 62.3+/-5.7 years-old and EF 28.5% (Q1: 20 Q3:42.7). One patient (16.7%) had two prior catheter ablation, four (66.7%) had one and one patient had no prior ablation, but had severe pulmonary fibrosis after COVID and was O2 dependent. The mean PTV (planning target volume) was 85+/-14 mL and the ITV (internal target volume) was 29+/-4 ml, with safe constraints regarding the esophagus and stomach. In a mean FU of 244+/-173days, 3 (50%) patients presented VT recurrence after blanking period. Two patients died 86 and 50 days after SBRT. The median number of VT episodes reduced from 13 (6.25;44.75) to 7.5 (3;7.5) (P = 0.093). All alive patients stop presenting VT in a median period of 174 (Q1: 44.75: Q3: 199) days, being at the end of the follow-up in a median of 196 (Q1: 137;Q3: 246) days without new VT episodes. Conclusion(s): SBRT presents a high rate of early recurrence in Chagas disease patients that improves during timeCopyright © 2023

Peculiar Aspects of Patients with Inherited Arrhythmias during the COVID-19 Pandemic

Since December 2019 we have observed the rapid advance of the severe acute respiratory syndrome caused by the new coronavirus (SARS-CoV-2). The impact of the clinical course of a respiratory infection is little known in patients with hereditary arrhythmias, due to the low prevalence of these diseases. Patients who present with infectious conditions may exacerbate hidden or well-controlled primary arrhythmias, due to several factors, such as fever, electrolyte disturbances, drug interactions, adrenergic stress and, eventually, the septic patient's own myocardial damage. The aim of this review is to highlight the main challenges we may encounter during the Covid 19 pandemic, specifically in patients with hereditary arrhythmias, with emphasis on the congenital long QT syndrome (LQTS), Brugada syndrome (SBr), ventricular tachycardia polymorphic catecholaminergic (CPVT) and arrhythmogenic right ventricular cardiomyopathy.