Effectiveness of cardioneuroablation in different subtypes of vasovagal syncope

BACKGROUND Cardioneuroablation(CNA)has shown encouraging results in patients with vasovagal syncope(VVS).However,data on different subtypes was scarce.METHODS This observational study retrospectively enrolled 141 patients[mean age:40±18 years,51 males(36.2%)]with the diagnosis of VVS.The characteristics among different types of VVS and the outcomes after CNA were analyzed.RESULTS After a mean follow-up of 4.3±1.5 years,41 patients(29.1%)experienced syncope/pre-syncope events after CNA.Syncope/pre-syncope recurrence significantly differed in each subtype(P=0.04).The cardioinhibitory type of VVS had the lowest recurrence rate after the procedure(n=6,16.7%),followed by mixed(n=26,30.6%)and vasodepressive(n=9,45.0%).Additionally,a significant difference was observed in the analyses of the Kaplan-Meier survival curve(P=0.02).Syncope/pre-syncope burden was significantly reduced after CNA in the vasodepressive type(P<0.01).Vasodepressive types with recurrent syncope/pre-syncope after CNA have a lower baseline deceleration capacity(DC)level than those without(7.4±1.0 ms vs.9.0±1.6 ms,P=0.01).Patients with DC<8.4 ms had an 8.1(HR=8.1,95%CI:2.2-30.0,P=0.02)times risk of syncope/pre-syncope recurrence after CNA compared to patients with DC≥8.4 ms,and this association still existed after adjusting for age and sex(HR=8.1,95%CI:2.2-30.1,P=0.02).CONCLUSIONS Different subtypes exhibit different event-free rates.The vasodepressive type exhibited the lowest event-free rate,but those patients with DC≥8.4 ms might benefit from CNA.

Management and therapy of vasovagal syncope: A review

Vasovagal syncope is a common cause of recurrent syncope. Clinically, these episodes may present as an isolated event with an identifiable trigger, or manifest as a cluster of recurrent episodes warranting intensive evaluation. The mechanism of vasovagal syncope is incompletely understood. Diagnostic tools such as implantable loop recorders may facilitate the identification of patients with arrhythmia mimicking benign vasovagal syncope. This review focuses on the management of vasovagal syncope and discusses the non-pharmacological and pharmacological treatment options, especially the use of midodrine and selective serotonin reuptake inhibitors. The role of cardiac pacing may be meaningful for a subgroup of patients who manifest severe bradycardia or asystole but this still remains controversial.

Deceleration Capacity--A Novel Measure for Autonomic Nervous System in Patients with Vasovagal Syncope on Tilt-table Testing

This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope(VVS) during head-up tilt-table testing(HUT). HUT was performed in 68 patients with unexplained syncope and 18 healthy subjects served as control group. According to whether bradycardia, hypotension or both took place during the onset of syncope, the patients were divided during the test into three subgroups: vasodepressor syncope(VD), cardioinhibitory syncope(CI) and mixed syncope(MX) subgroups. Heart rate, blood pressure, heart rate variability(HRV), and deceleration capacity(DC) were continuously analyzed during HUT. For all the subjects with positive responses, the normalized low frequency(LFn) and the LF/HF ratio markedly decreased whereas normalized high frequency(HFn) increased when syncope occurred. Syncopal period also caused more significant increase in the power of the DC in positive groups. These changes were more exaggerated compared to controls. All the patients were indicative of a sympathetic surge in the presence of withdrawal vagal activity before syncope and a sympathetic inhibition with a vagal predominance at the syncopal stage by the frequency-domain analysis of HRV. With the measurements of DC, a decreased vagal tone before syncope stage and a vagal activation at the syncopal stage were observed. The vagal tone was higher in subjects showing cardioinhibitory responses at the syncopal stage. DC may provide an alternative method to understand the autonomic profile of VVS patients.

Different treatments for different mechanisms in vasovagal syncope

The treatment of vasovagal syncope has been by far unsatisfactory. Beta-blockers may prevent vasovagal syncope, but they exacerbates heart asystole. Cardiac pacing prevents syncope but notpresyncope. The frequent, serious vasovagal syncope attacks of a 63- year-old woman patient were completely prevented by administration of 100 mg metoprolol (b.i.d) for 3 months until the patient experienced a complete heart block. A DDD pacemaker implantation abolished syncope but not the presyncope, which was eventually prevented in a follow-up period of 24 months by adding 75 mg atenalol twice a day. This case suggests a different mechanism involved in vasovagal syncope.

Myoclonus and Recurrent Cardioinhibitory Vasovagal Syncope after Abdominal Surgery in a Critical Care Setting

Letter to the

Minimal Vasovagal Dysautonomia in Patients with Rare or Unique Syncope

Introduction: It is common to find people sent to perform a Head Up Tilt Test (HUT) who suffered a single syncope, or syncopes that occur during certain periods and never appear again. We wonder how these people are different from those who have never had syncope. Methods: We found 300 patients who suffered only one (unique) or a maximum of 5 vasovagal syncopes during their life. And their HUT was positive for vasovagal dysautonomia. We compared them, with 120 healthy volunteers who have never had syncope. We try to explain how some constitutional predisposing factors act in these patients, and are associated with environmental triggers to precipitate the syncope. Results: We found differences between cases and controls in predisposing factors such as: heredity, joint hypermobility, baroreflex failure, venous compliance and some neurological diseases. Then an environmental factor acts as a trigger for syncope: prolonged standing, stress, pain and emotions, dehydration, use of certain drugs, abundant food. Conclusions: There are people with minimally expressed vasovagal dysautonomia who have an organic predisposition to present vasovagal syncopes (heredity, joint hypermobility, baroreflex failure, venous compliance, some neurological diseases, etc.). But this predisposition is not enough by itself to produce syncopes. One or more environmental factors must be added, acting as a trigger that would be the reason why these episodes are so infrequent.

Predictive Value of Blood Pressure,Heart Rate,and Blood Pressure/Heart Rate Ratio in a Chinese Subpopulation with Vasovagal Syncope

Objective:The head-up tilt test(HUTT)is widely used but is time-consuming and not cost-effective to evaluate patients with vasovagal syncope(VVS).The present study aims to verify the hypothesis that ambulatory blood pressure(BP)monitoring(ABPM)and the simplistic tilt test may be potential alternatives to the HUTT.Methods:The study consecutively enrolled 360 patients who underwent the HUTT to evaluate VVS.BP),heart rate(HR),and BP/HR ratios derived from ABPM and the simplistic tilt test were evaluated to predict the presence,pattern,and stage of syncope during the HUTT.Results:Mixed response was the commonest pattern,and syncope occurred frequently with infusion of isoproterenol at a rate of 3μg/min.During the simplistic tilt test,the cardioinhibitory group had higher tilted BP/HR ratios than the vasodepressor group,while the vasodepressor group had a faster tilted HR and a larger HR difference than the cardioinhibitory group.The higher the BP/HR ratio in the tilted position,the higher the isoproterenol dosage needed to induce a positive response.During ABPM,BP/HR ratios were signifi cantly higher in the cardioinhibitory group than in the vasodepressor group.The higher the ABPM-derived BP,the higher the dosage of isoproterenol needed to induce syncope.There were signifi cant correlations in BP/HR ratios between ABPM and the supine position in the vasodepressor group,while signifi cant correlation was found only for the diastolic BP/HR ratio between ABPM and the tilted position in the cardioinhibitory group.The mixed pattern shared correlative features of the other two patterns.Conclusion:ABPM and the simplistic tilt test might be used as promising alternatives to the HUTT in VVS evaluation in clinical settings.

The Changes of Baroreflex Sensitivity During Head-up Tilt Test and Its Clinical Significance in the Patients with Vasovagal Syncope

Objective To study thechanges of baroreflex sensitivity (BRS) during head - up tilt test (HUT) in patients with vasovagal syncope (VS), and to examine the relationship between baroreflex sensitivity and neurohormonal factors. Furthermore, to investigate the effects of the changes of BRS on VS. Methods Forty - two patients with unexplained syncope (Among the 42 patients, there were 22 patients with positive HUT and 20 patients with negative HUT respectively) and 20 healthy volunteers (with negative HUT) underwent passive head - up tilt testing, Ante-cubital vein blood samples were taken before and after HUT, or at syncope. The fasting plasma endothelin , serum nitric oxide (NO), serum NE were measured, the BRS was assessed on the basis of the linear regression slope the RR interval versus systolic arterial blood pressure during the increment in blood pressure after intravenous administration of phenylephrine. Results (1) During the syncope, the BRS significantly reduced in HUT(+) group than baseline. At the end of tilt, the level of plasma ET, serum NO in patients with positive HUT significantly increased compared with baseline or normal controls, and the plasma concentration of NE also had the trend of increase. (2) By multiple regression analysis, a significant negative correlation was found between baroreceptor sensitivity and the plasma ET, NO at the end of HUT in patients with positive HUT, but there was no relationship between BRS and NE. Conclusions During the syncope occure, the BRS in patients with VS decreased significantly compared with normal controls. The abnormal plasma ET, NO concen-tration might contribute to the mechanism of VS.

A Cognitive Behavioural Intervention for the Treatment of Vasovagal and Unexplained Syncope

Vasovagal syncope and unexplained syncope are the most commonly observed types of syncope in outpatient and hospital settings. Medical interventions usually target at the physiological mechanisms responsible for loss of consciousness in an attempt to limit the frequency of recurrences. However, this type of intervention does not take into account the psychological and functional impact of syncope, nor the importance of psychological variables in triggering and maintaining syncope. In the present pilot study, four participants presenting significant psychological distress and recurrent syncope were treated using a multimodal intervention targeting at both the medical and psychological aspects of the problem. Results showed a significant reduction in the frequency of syncope/presyncope, in the level of emotional distress experienced, as well as improved functional status in three of the four participants. Several recommendations are made to medical practitioners and psychologists, in view of identifying patients likely to benefit from this type of intervention or components thereof.

Evaluation of cilazapril in vasovagal syncope treatment

Objective：to evaluate cilazapri[ in vasovsgal syncope treatment. Method: eighty-six cases of VVS patients found positive in TTT tilt were medicated with 2.5 mg eilazapril daily for three months and followed up by TTT. Results: seven cases quit due to cough or unexplained reason; 79 VVS patients had no more fainting spells; 75.95% of TTT results of patients changed to negative after 3 months therapy. The before and after cilazaptil treatment average blood pressures (taken in lying position) were 121/73 ram Pig (1 mm Hg=0. 133kPa) and 120/76 mm Pig reapectively (P>0.05); and mean heart rates were 68.63±12.37/min and 70.13±13.15/min reapectively with no significant changes (P > 0.05). Conclusion: CUazapril was effective in treatment of VVS; did not affect normal blood pressure and heart rate; was safe; and had little side effect.

Cause analysis of vasovagal syncope induced by treadmill exercises test

AIM:To evaluate the treadmill exercise t est on vasovagal syncope and the avoidance steps.METHOD:Examination of treadmill exercise t est of 64adults and analyse of the history,pr etest heart rate,the maximum heart r ate,metabolic equivalent (MET)and tilt table test.RESULTS:Exercise tolerances in both groups were same with signifi cantly increase of syncope history(43/64,67%in syncope group,while 11/64or 9%in the controls)and lower basic heart rate of the subjects(74±11in the syncope group;66±10in t he con-trols,with P<0.01statistically)in the syncope group.HUTT positive s ub-jects were significantly more in the syncope group(48/64,75%)than in the controls(2/64),with P<0.01statistically.CONCLUSION:The exercise syncope was based on the pretest heart rate and previous syncopal history rather than the exercise tolerance in healt h adults.It suggested an underlying abnor-mality which may predispose to exerc ise subjects with vasovagal syncope.

Nursing Care of 10 Patients with Vasovagal Reflex Caused by Artificial Liver Support System Treatment

This study outlines the essential nursing strategies employed in the care of 10 patients experiencing vascular vagal reflex, managed with artificial liver support systems. It highlights a holistic nursing approach tailored to the distinct clinical manifestations of these patients. Key interventions included early detection of psychological issues prior to initiating treatment, the implementation of comprehensive health education, meticulous monitoring of vital signs throughout the therapy, prompt emergency interventions when needed, adherence to prescribed medication protocols, and careful post-treatment observations including venous catheter management. Following rigorous treatment and dedicated nursing care, 7 patients demonstrated significant improvement and were subsequently discharged.

A Case Report of Recurrent Guillain-Barré Syndrome with Orthostatic Hypotension Syncope as the First Symptom

Guillain⁃Barré syndrome (GBS) is an immune-mediated peripheral neuropathy with acute or subacute onset of flaccid paralysis of the limbs with symmetrical hypesthesia and autonomic nerve involvement [1]. The clinical manifestations of autonomic nerve damage are complex and varied, which may involve extensive or limited autonomic function damage, including abnormalities of the skin, pupil, urinary tract, gastrointestinal tract, cardiovascular system, body temperature, lacrimal and salivary glands, and sexual function, etc. [2], and some patients may even have autonomic nerve damage as the only symptom, which is a variant of GBS and is prone to misdiagnosis or underdiagnosis. Recurrence of GBS is rare, and the manifestations of recurrence are often similar to those of the first symptoms [3], but the patient admitted to our hospital had syncope as the main clinical manifestation of recurrence, which was completely different from that of the first incidence, and syncope is not a common and typical clinical manifestation of GBS, so misdiagnosis is highly likely.

Analysis of Factors Related to Vasovagal Response in Apheresis Blood Donors and the Establishment of Prediction Model Based on BP Neural Network Algorithm

Objective:To analyze the factors related to vessel vasovagal reaction(VVR)in apheresis donors,establish a mathematical model for predicting the correlation factors and occurrence risk,and use the prediction model to intervene in high-risk VVR blood donors,improve the blood donation experience,and retain blood donors.Methods:A total of 316 blood donors from the Xi'an Central Blood Bank from June to September 2022 were selected to statistically analyze VVR-related factors.A BP neural network prediction model is established with relevant factors as input and DRVR risk as output.Results:First-time blood donors had a high risk of VVR,female risk was high,and sex difference was significant(P value<0.05).The blood pressure before donation and intergroup differences were also significant(P value<0.05).After training,the established BP neural network model has a minimum RMS error of o.116,a correlation coefficient R=0.75,and a test model accuracy of 66.7%.Conclusion:First-time blood donors,women,and relatively low blood pressure are all high-risk groups for VVR.The BP neural network prediction model established in this paper has certain prediction accuracy and can be used as a means to evaluate the risk degree of clinical blood donors.

Predicting short-term adverse outcomes in the geriatric population presenting with syncope:a comparison of existing syncope rules and beyond

OBJECTIVES Syncope at age 65+is associated with increased mortality,irrespective of cause.Syncope rules were designed to aid in risk-stratification but were only validated in the general adult population.Our objective was to determine if they can be applied to a geriatric population in predicting short-term adverse outcomes.METHODS In this single-center retrospective study,we evaluated 350 patients aged 65+presenting with syncope.Exclusion criteria included confirmed non-syncope,active medical condition,drug or alcohol-related syncope.Patients were stratified into high or low risk based on Canadian Syncope Risk Score(CSRS),Evaluation of Guidelines in Syncope Study(EGSYS),San Francisco Syncope Rule(SFSR),and Risk Stratification of Syncope in the Emergency Department(ROSE).Composite adverse outcomes at 48-hour and 30-day included all-cause mortality,major adverse cardiac and cerebrovascular events(MACCE),return emergency department visit,hospitalization,or medical intervention.We assessed each score's ability to predict the outcomes using logistic-regression and compared performances using receiver-operator curves.Multivariate analyses were performed to study the associations between recorded parameters and outcomes.RESULTS CSRS outperformed with AUC of 0.732(95%CI:0.653-0.812)and 0.749(95%CI:0.688-0.809)for 48-h and 30-day outcomes,respectively.Sensitivities for CSRS,EGSYS,SFSR,and ROSE for 48-hour outcomes were 48%,65%,42% and 19%;and for 30-day outcomes were 72%,65%,30% and 55%,respectively.Atrial fibrillation/flutter on EKG,congestive heart failure,antiarrhythmics,systolic blood-pressure<90 at triage,and associated chest pain highly correlated with 48-h outcomes.An EKG abnormality,heart disease history,severe pulmonary hypertension,BNP>300,vasovagal predisposition,and antidepressants highly correlated with 30-day outcomes.CONCLUSIONS Performance and accuracy of four prominent syncope rules were suboptimal in identifying high-risk geriatric patients with short-term adverse outcomes.We identified some significant clinical and laboratory information that may play a role in predicting short-term adverse events in a geriatric cohort.

Improving the approach to non-cardiac syncope in the emergency department observation unit

Syncope is a rather frequent condition,responsible for1.0%–1.5%of emergency department (ED) visits.[1]Even if the development of clinical guidelines has improved the ED management of syncope,[2]the hospitalization rate is still very high (up to 50%),especially compared with the incidence of short-term adverse events,which is11%globally,but decreases to less than 4%when events already diagnosed in the ED are excluded,[1]meaning that most patients will not benefit from admission.

Arrhythmic syncope: From diagnosis to management

Syncope is a concerning symptom that affects a large proportion of patients.It can be related to a heterogeneous group of pathologies ranging from trivial causes to diseases with a high risk of sudden death.However,benign causes are the most frequent,and identifying high-risk patients with potentially severe etiologies is crucial to establish an accurate diagnosis,initiate effective therapy,and alter the prognosis.The term cardiac syncope refers to those episodes where the cause of the cerebral hypoperfusion is directly related to a cardiac disorder,while arrhythmic syncope is cardiac syncope specifically due to rhythm disorders.Indeed,arrhythmias are the most common cause of cardiac syncope.Both bradyarrhythmia and tachyarrhythmia can cause a sudden decrease in cardiac output and produce syncope.In this review,we summarized the main guidelines in the management of patients with syncope of presumed arrhythmic origin.Therefore,we presented a thorough approach to syncope work-up through different tests depending on the clinical characteristics of the patients,risk stratification,and the management of syncope in different scenarios such as structural heart disease and channelopathies.

Cost-effectiveness of diagnostic approaches to vasovagal syncope in children and adolescents in China： a health economic analysis

Background Syncope is a common clinical problem with multiple causes. Vasovagal syncope （VVS） is by far the most frequent cause of syncope in children and adolescents. The traditional diagnostic approach to VVS of children and adolescents is based on a series of tests to exclude all other causes, which is complex and time and medical resource consuming. Attempts have been made to develop a new cost-effective diagnostic approach to avoid these problems. This study aimed to compare the economic effectiveness and diagnostic value of the traditional diagnostic approach to VVS of children with a new diagnostic approach. Methods One hundred and eighteen children diagnosed as VVS were divided into two groups according to the different diagnostic approaches. The diagnostic value of the two diagnostic approaches was then analyzed. Meanwhile, the costs of hospitalization, diagnostic testing and hospital stay were determined. Data were evaluated by the cost-minimization analysis. Results The diagnostic value of the new diagnostic approach was similar to that of the traditional diagnostic approach （56.57% vs. 53.91%, P=0.697）. However, the cost of hospitalization per patient by the new diagnostic approach was （1507.08±144.63） Yuan （RMB） which was less than that of the traditional diagnostic approach （2603.64±2.08.19） Yuan. The costs of diagnostic tests per patient by the new diagnostic approach was （1256.04±109.14） Yuan and by the traditional approach （2175.22±153.32） Yuan. Conclusion Compared to the traditional diagnostic approach to diagnose VVS in children and adolescents, the new diagnostic approach is of a good economic value, and it should be popularized in clinical practice.

Pathophysiology and Individualized Management of Vasovagal Syncope and Postural Tachycardia Syndrome in Children and Adolescents:An Update

Vasovagal syncope(VVS) and postural tachycardia syndrome(POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated syncope.In recent years,increasing attention has been paid to the management of VVS and POTS in children and adolescents.A number of potential mechanisms are involved in their pathophysiology,but the leading cause of symptoms varies among patients.A few studies thus have focused on the individualized treatment of VVS or POTS based on selected hemodynamic parameters or biomarkers that can predict the therapeutic effect of certain therapies and improve their effectiveness.This review summarizes the latest developments in individualized treatment of VVS and POTS in children and indicates directions for further research in this field.