Therapeutic options for neurocardiogenic syncope: a meta-analysis of randomised trials with and without blinding

BACKGROUND

Neurocardiogenic syncope is a common condition with significant associated psychological and physical morbidity. The effectiveness of therapeutic options for neurocardiogenic syncope beyond placebo remains uncertain.

METHODS

The primary endpoint was the risk ratio (RR) of spontaneously recurring syncope following any therapeutic intervention. We also examined the effect of blinding on treatment efficacy. We identified all randomised trials which evaluated the effect of any pharmacological, device-based or supportive intervention on patients with a history of syncope. A systematic search was conducted on Medline, Embase, PubMed databases and Cochrane Central Register for Controlled Trials from 1950 to 25 April 2023. Event rates, their RRs and 95% CIs were calculated, and a random-effects meta-analysis was conducted for each intervention. Data analysis was performed in R using RStudio.

RESULTS

We identified 47 eligible trials randomising 3518 patients. Blinded trials assessing syncope recurrence were neutral for beta blockers, fludrocortisone and conventional dual-chamber pacing but were favourable for selective serotonin reuptake inhibitors (SSRIs) (RR 0.40, 95% CI 0.26 to 0.63, p<0.001), midodrine (RR 0.70, 95% CI 0.53 to 0.94, p=0.016) and closed-loop stimulation (CLS) pacing (RR 0.15, 95% CI 0.07 to 0.35, p<0.001). Unblinded trials reported significant benefits for all therapy categories other than beta blockers and consistently showed larger benefits than blinded trials.

CONCLUSIONS

Under blinded conditions, SSRIs, midodrine and CLS pacing significantly reduced syncope recurrence. Future trials for syncope should be blinded to avoid overestimating treatment effects.

PROSPERO REGISTRATION NUMBER

CRD42022330148.

The efficacy of non-pharmacological and non-pacing therapies in preventing vasovagal syncope: Tilt training, physical counter pressure maneuvers, and yoga - A systematic review and meta-analysis

BACKGROUND

Vasovagal syncope (VVS) is a prevalent condition characterized by a sudden drop in blood pressure and heart rate, leading to a brief loss of consciousness and postural control. Recurrent episodes of VVS significantly impact the quality of life and are a common reason for emergency department visits. Non-pharmacological interventions, such as tilt training, physical counter pressure maneuvers, and yoga, have been proposed as potential treatments for VVS. However, their efficacy in preventing VVS remains uncertain.

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines. PubMed, Web of Science, and Embase were searched up to March 2023 for randomized controlled trials comparing non-pharmacological interventions with control in preventing VVS recurrence. The primary outcome was the recurrence rate of VVS episodes.

RESULTS

A total of 1130 participants from 18 studies were included in the meta-analysis. The overall mean effect size for non-pharmacological interventions versus control was 0.245 (95 % CI: 0.128-0.471, p-value <0.001). Subgroup analysis showed that yoga had the largest effect size (odds ratio 0.068, 95 % CI: 0.018-0.250), while tilt training had the lowest effect size (odds ratio 0.402, 95 % CI: 0.171-0.946) compared to control. Physical counter pressure maneuvers demonstrated an odds ratio of 0.294 (95 % CI: 0.165-0.524) compared to control.

CONCLUSION

Non-pharmacological interventions show promise in preventing recurrent VVS episodes. Yoga, physical counter pressure maneuvers, and tilt training can be considered as viable treatment options. Further research, including randomized studies comparing pharmacological and non-pharmacological approaches, is needed to evaluate the safety and efficacy of these interventions for VVS treatment.

Clinical Efficacy of Catheter Ablation in the Treatment of Vasovagal Syncope

Catheter ablation of ganglionated plexi (GPs) performed as cardioneuroablation in the left atrium (LA) has been reported previously as a treatment for vasovagal syncope (VVS). However, the efficacy and safety of catheter ablation in the treatment of VVS remains unclear. The objective of this study is to explore the efficacy and safety of catheter ablation in the treatment of VVS and to compare the different ganglion-mapping methods for prognostic effects. A total of 108 patients with refractory VVS who underwent catheter ablation were retrospectively enrolled. Patients preferred to use high-frequency stimulation (HFS) (n = 66), and anatomic landmark (n = 42) targeting is used when HFS failed to induce a positive reaction. The efficacy of the treatment is evaluated by comparing the location and probability of the intraoperative vagal reflex, the remission rate of postoperative syncope symptoms, and the rate of negative head-up tilt (HUT) results. Adverse events are analyzed, and safety is evaluated. After follow-up for 8 (5, 15) months, both HFS mapping and anatomical ablation can effectively improve the syncope symptoms in VVS patients, and 83.7% of patients no longer experienced syncope (<0.001). Both approaches to catheter ablation in the treatment of VVS effectively inhibit the recurrence of VVS; they are safe and effective. Therefore, catheter ablation can be used as a treatment option for patients with symptomatic VVS.

Management of vasovagal syncope

Vasovagal syncope (VVS) is a very common form of fainting. Treatment begins with patient education about the mechanism of fainting, and the non-lethal nature of vasovagal syncope. In this article, we review several non-pharmacological approaches that form the foundation of our current treatments. These include increases in dietary salt and water intake, the use of compression garments, physical counter-maneuvers and tilt-training. When these approaches are inadequate, medications can sometimes be effective. While the evidence base for the pharmacological treatment of VVS is modest, recent trial data have found drugs to be useful in placebo-controlled randomized trials. For select patients, and those patients more refractory to medications, procedural treatments may be an option. In this review, we discuss the current state of evidence for the non-pharmacological and pharmacological treatments for VVS, as well as some novel, emerging therapies for VVS.

Cardioneuroablation changes the type of vasovagal response in patients with asystolic reflex syncope

BACKGROUND

Cardioneuroablation (CNA) has been recently proposed as a new therapy in patients with asystolic vasovagal syncope (VVS) caused by parasympathetic overactivity.

OBJECTIVE

To assess the impact of CNA on the type of VV response during tilt testing (TT).

METHODS

The study group consisted of 20 patients (7 males, mean age 38 ± 9). All patients had a history of syncope due to asystole and confirmed asystolic VVS at baseline TT (TT₁). CNA was performed in the right and left atrium. The second TT (TT₂) and Holter ECG were performed three months later. All patients completed one-year follow up.

RESULTS

At TT₁, twenty patients had cardioinhibitory syncope and 1 had mixed VVS with asystole > 3 s. During one-year follow-up no spontaneous syncopal episodes were noted. At TT2, 6 patients had no syncope whereas the remaining 13 had syncope - twelve due to vasodepressor mechanism and only one due to asystole. Mean heart rate after CNA was significantly faster and heart rate variability parameter (SDNN) lower than before the procedure (82 ± 9 vs 69 ± 11 beats/min, p = 0.0003 and 74 ± 22 vs 143 ± 40 ms, p = 000001, respectively). These changes were similar in those who fainted during TT₂ and those who did not (84 ± 10 vs 81 ± 5 beats/min, p = NS and 72 ± 24 vs 72 ± 19 ms, p = NS, respectively).

CONCLUSIONS

CNA profoundly affects type of VV reaction causing normalization of the response to tilting or changing cardiodepression to vasodepression. Changes in heart rate and heart rate variability are consistent with attenuation of parasympathetic activity.

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.

Baroreflex Sensitivity Predicts Response to Metoprolol in Children With Vasovagal Syncope: A Pilot Study

Objective: To explore the role of baroreflex sensitivity (BRS) in the head-up tilt test (HUTT) in predicting the therapeutic response of vasovagal syncope (VVS) patients to metoprolol. Materials and Methods: Vasovagal syncope patients treated with metoprolol were enrolled in this study and were classified as responders or non-responders according to changes in their symptom scores before and after metoprolol treatment. Values of BRS in the supine position and at positive response occurrence in the HUTT were obtained, and BRS changes from supine to positive response occurrence were calculated. Differences between responders and non-responders were analyzed. Receiver operating characteristic curve analysis was performed to assess the value of BRS for predicting the therapeutic efficacy of metoprolol in pediatric patients with VVS. Results: Forty patients (14 boys; 11.8 ± 2.5 years) diagnosed with VVS were recruited in the study, 28 of whom were verified to be responders to metoprolol and 12 of whom were verified as non-responders. They did not show any differences in baseline characteristics and hemodynamics in the HUTT (p > 0.05). However, the responders had an obviously increased supine BRS value compared to the non-responders (16.9 ± 7.7 ms/mmHg vs. 7.6 ± 3.8 ms/mmHg; p < 0.01). No difference in BRS at positive response occurrence was observed between the two groups (8.9 ± 8.5 ms/mmHg vs. 10.6 ± 9.8 ms/mmHg; p > 0.05). Accordingly, the changes in the BRS of responders were more obvious than in non-responders (8.0 ± 7.8 ms/mmHg vs. -3.0 ± 10.4 ms/mmHg; p < 0.01). The area under the receiver operating characteristic curve for the predictive value of supine BRS was 0.887 (95% CI, 0.779-0.995; p < 0.01). A cut-off value of 10 ms/mmHg yielded a sensitivity and specificity of 82 and 83%, respectively, in predicting the therapeutic efficacy of metoprolol in pediatric VVS patients. The area under the receiver operating characteristic curve for the predictive value of BRS changes was 0.827 (95% CI, 0.693-0.962; p < 0.01). A cut-off value of 4 ms/mmHg yielded a sensitivity and specificity of 71 and 83%, respectively. Conclusion: Baroreflex sensitivity may predict the response of children with VVS to metoprolol.

Diagnostic and therapeutic approach to cardioinhibitory reflex syncope: A complex and controversial issue

Syncope is defined as a transient loss of consciousness due to global cerebral hypoperfusion and is one of the leading causes of emergency department admission. The initial approach should focus on excluding non-syncopal causes for loss of consciousness and risk stratification for cardiac cause, in order to ensure an appropriate etiological investigation and therapeutic approach. Vasovagal syncope (VVS), the most common type of syncope, should be assumed once other causes are excluded. Pathophysiologically, the vasovagal reflex is the result of a paradoxical autonomic response, leading to hypotension and/or bradycardia. VVS has not been shown to affect mortality, but morbidity may be considerable in those with recurrent syncopal episodes. The management of VVS includes both non-pharmacological and pharmacological measures that act on various levels of the reflex arc that triggers the syncopal episode. However, most are of uncertain benefit given the scarcity of high-quality supporting evidence. Pacemaker therapy may be considered in recurrent refractory cardioinhibitory reflex syncope, for which it is currently considered a robust intervention, as noted in the European guidelines. Non-randomized and unblinded studies have shown a potential benefit of pacing in recurrent VVS, but double-blinded randomized controlled trials have not consistently demonstrated positive results. We performed a comprehensive review of the current literature and recent advances in cardiac pacing and pacing algorithms in VVS, and discuss the diagnostic and therapeutic approach to the complex patient with recurrent VVS and reduced quality of life.

Long-Term Outcomes of Children and Adolescents With Postural Tachycardia Syndrome After Conventional Treatment

Objectives: To explore the long-term outcomes of children and adolescents with postural tachycardia syndrome receiving conventional interventions. Materials and Methods: A total of 121 patients were recruited, but 6 (5.0%) of them were lost at follow-up. The detailed clinical data were collected, and the reoccurrence and frequency of orthostatic intolerance symptoms were evaluated with a mean followed-up period of 18.7 months (range, 14-74 months). The Kaplan-Meier curve was used to show the cumulative symptom-free rate of patients over time. Factors influencing the long-term outcomes were examined using the Cox's proportional hazards models. Results: The cumulative symptom-free rate was gradually increased over time. It was 48.4% at the 1-year follow-up and increased to 85.6% at the 6-year follow-up. The duration of symptoms before treatment and the maximum upright heart rate in standing-up test were identified as independent indicators for the long-term outcomes. Each 1-month prolongation in the duration of symptoms before treatment was associated with a 1.2% decrease in the cumulative symptom-free rate. However, each 1-bpm increase in the maximum upright heart rate in standing-up test was associated with a 2.1% increase in the cumulative symptom-free rate. Conclusions: The long-term outcomes of postural tachycardia syndrome patients who received conventional interventions are benign and the cumulative symptom-free rate was gradually increased over time. The prolonged duration of symptoms before treatment and the reduced maximum upright heart rate in standing-up test are the independent risk indicators.

Acceleration Index Predicts Efficacy of Orthostatic Training on Vasovagal Syncope in Children

OBJECTIVE

To explore the value of the acceleration index as a predictor of therapeutic response to orthostatic training in children with vasovagal syncope (VVS).

STUDY DESIGN

Thirty-three children with VVS were recruited and treated with orthostatic training. The therapeutic response of each patient was evaluated after 3 months of treatment. A Pearson correlation was calculated between the acceleration index and the severity of VVS. The value of the acceleration index in predicting the therapeutic response to orthostatic training was assessed by analysis of the receiver operating characteristic curve.

RESULTS

Among the 33 children with VVS, 20 were found to be responders and the remaining were nonresponders. The mean acceleration index was significantly lower in responders compared with nonresponders (21.10 ± 6.61 vs 31.36 ± 9.00; P = .001) and it was negatively correlated with positive response time in the head-up tilt test, with systolic blood pressure and with diastolic blood pressure at positive response time in the head-up tilt test (P < .05). The receiver operating characteristic curve for the predictive value of the acceleration index showed that the area under the curve was 0.827 (95% CI, 0.676-0.978; P = .002), and a cutoff value of the acceleration index of 26.77 yielded a sensitivity of 85.0% and a specificity of 69.2%.

CONCLUSIONS

The acceleration index may be useful for predicting the efficacy of orthostatic training on VVS in children.

Orthostatic cardiovascular profile of subjective well-being

Previous clinical and elderly population studies have found that affective well-being can be assessed by clino-orthostatic cardiovascular reactivity. This study explored this relationship in a young healthy sample, and with respect to cognitive appraisals of well-being. Four successive readings of blood pressure (BP) and heart rate (HR) after lying down (clinostatic probe) followed by four successive readings after standing up (orthostatic probe) were obtained from 52 healthy students along with questionnaire-reported well-being. Analyses indicated that a deeper drop of systolic BP (SBP) and mean arterial (MAP) pressure during supine was related to higher positive mood, but higher and more stable orthostatic MAP and HR response were related to lower negative mood. A higher diastolic BP while standing upright and lower SBP in general were associated with higher optimism and higher global life satisfaction, respectively. The findings confirm previous results and indicate that cognitive appraisals of well-being are also related to BP regulation.

Catheter Ablation as a Treatment for Vasovagal Syncope: Long-Term Outcome of Endocardial Autonomic Modification of the Left Atrium

Background

Autonomic modification through catheter ablation of ganglionated plexi (GPs) in the left atrium has been reported previously as a treatment for vasovagal syncope. This study aimed to observe the long‐term outcome in a larger cohort.

Methods and Results

A total of 57 consecutive patients (aged 43.2±13.4 years; 35 women) with refractory vasovagal syncope were enrolled, and high‐frequency stimulation and anatomically guided GP ablation were performed in 10 and 47 cases, respectively. A total of 127 GP sites with positive vagal response were successfully elicited and ablated, including 52 left superior, 19 left lateral, 18 left inferior, 27 right anterior, and 11 right inferior GPs. During follow‐up of 36.4±22.2 months (range 12–102 months), 52 patients (91.2%) remained free from syncope. Prodromes recurred in 16 patients. No statistical differences were found between the high‐frequency stimulation and anatomically guided ablation groups in either freedom from syncope (100% versus 89.4%, P=0.348) or recurrent prodromes (50% versus 76.6%, P=0.167). The deceleration capacity, heart rate, and heart rate variability measurements demonstrated a reduced vagal tone lasting for at least 12 months after the procedure, with improved tolerance of repeated head‐up tilt testing. No complications were observed except for transient sinus tachycardia that occurred in 1 patient.

Conclusions

Left atrial GP ablation showed excellent long‐term clinical outcomes and might be considered as a therapeutic option for patients with symptomatic vasovagal syncope.

Home Orthostatic Training in Elderly Patients with Vasovagal Syncope - A Prospective Randomised Controlled Trial

Aim: The aim of this study was to assess the effect of home orthostatic training (HOT) on autonomic reflexes in elderly patients with vasovagal syncope (VVS). Methods: Design and Setting: A single-blind randomised control trial was conducted at Eastbourne District General Hospital, East Sussex NHS Trust. Patients: Individuals with recurrent syncope underwent tilt-table testing between August 2007 and October 2009.Those with at least two syncopal episodes and tilt-test proven VVS were recruited. Participants were divided into those aged >65 years (O65) and those aged <65 years (U65). Interventions: Patients in the O65 group were randomised 1:1 to receive active HOT (O65+) or sham HOT (O65-). The U65 group received active HOT. Participants performed HOT/sham HOT and recorded their training and symptoms. Patients had a repeat tilt test at 3 months. Outcome Measures: Time to syncope at repeat tilt-table testing, low-frequency heart rate variability (LF-HRV), high-frequency heart rate variability (HF-HRV), mean upslope baroreflex sensitivity (BRS) and mean downslope BRS were assessed. Results: A total of 106 patients with recurrent syncope underwent tilt-table testing. Of these, 45 consecutive patients (30 in the O65 group and 15 in the U65 group) were recruited. Two, one and three patients withdrew or were lost-to-follow-up in the O65+, O65-, and U65 groups, respectively. Symptomatic benefit occurred in four (31 %) of the O65+, four (29 %) of the O65-, and six (50 %) of the U65. None of the autonomic measures changed significantly in any group. No difference was seen with HF-HRV, LF-HRV mean upslope BRS and mean downslope BRS. Fifty per-cent of the O65+ group stopped training because of back pain. Time constraint (25 %) was the most common reason for cessation in the U65 group. Conclusions: Despite good tilt training compliance, no improvement in autonomic measures in any group was shown. The most common reason for cessation of training was back pain in the elderly groups. This study does not support the use of HOT in elderly patients.

Therapy for Syncope

The diagnostic process in patients with syncope is not always easy and includes a detailed clinical history, physical examination and baseline electrocardiogram; according to the results of these initial approaches, some additional tests must be performed. Using this strategy, the cause of syncope is diagnosed in 60% to 80% of patients; in the remaining patients, risk stratification can be established to identify those patients at risk of having cardiac events or death at midterm follow-up. This article reviews the treatment of patients with syncope according to the different causes.

Non-invasive management of vasovagal syncope

Vasovagal syncope (VVS) is a common disorder of the autonomic nervous system. While recurrent syncope can cause very impaired quality of life, the spells are not generally life-threatening. Both non-pharmacological and pharmacological approaches can be used to treat patients. Conservative management with education, exercise and physical maneuvers, and aggressive volume repletion is adequate for controlling symptoms in most patients. Unfortunately, a minority of patients will continue to have recurrent syncope despite conservative therapy, and they may require medications. These could include vasopressor agents, beta-blockers, or neurohormonal agents. Some patients may require more aggressive device based therapy with pacemakers or radiofrequency ablation, which are emerging therapies for VVS. This paper will review non-procedure based treatments for VVS.

Symptomatic presentation of carotid sinus hypersensitivity is associated with impaired cerebral autoregulation

Background

Carotid sinus hypersensitivity (CSH) is associated with syncope, unexplained falls, and drop attacks in older people but occurs asymptomatically in 35% of community‐dwelling elders. We hypothesized that impaired cerebral autoregulation is associated with the conversion of asymptomatic CSH to symptomatic CSH. We therefore conducted a case–control study evaluating individuals with CSH with and without the symptoms of syncope or unexplained falls, as well as non‐CSH controls, to determine whether the blood pressure and heart rate changes associated with CSH are associated with symptoms only when cerebral autoregulation is altered.

Methods and Results

Bilateral middle cerebral artery blood flow velocities (BFV) were measured in consecutive patients with symptomatic CSH (n=22) and asymptomatic controls with (n=18) and without CSH (n=14) using transcranial Doppler ultrasonography during lower body negative pressure‐induced systemic hypotension. Within‐group comparisons revealed significantly lower cerebrovascular resistance index (CVR_i) at nadir for the asymptomatic CSH group (right, mean [95% CI]: 2.2 [1.8, 2.8] versus 2.6 [2.2, 3.0]; P=0.005; left: 2.8 [2.4, 3.3] versus 3.1 [2.7, 3.8]; P=0.016). Between‐group comparisons showed higher mean BFV (right: estimated mean difference, B=5.49 [1.98, 8.80], P=0.003; left: 4.82 [1.52, 8.11], P=0.005) and lower CVR_i (right: B=0.08 [0.03, 0.12], P=0.003, left: B=0.07 [0.02, 0.12], P=0.006) in asymptomatic CSH versus symptomatic CSH groups. There were no significant differences in bilateral mean BFV or right CVR_i between the non‐CSH and symptomatic CSH groups but differences were present for left CVR_i (B=0.07 [0.02, 0.013], P=0.015).

Conclusion

Cerebral autoregulation is altered in symptomatic CSH and therefore appears to be associated with the development of hypotension‐related symptoms in individuals with CSH.

Syncope in the Elderly

A rapid change in ageing demographic is taking place worldwide such that healthcare professionals are increasingly treating old and very old patients. Syncope in the elderly is a challenging presentation that is under-recognised, particularly in the acute care setting. The reason for this is that presentation in the older person may be atypical: patients are less likely to have a prodrome, may have amnesia for loss of consciousness and events are frequently unwitnessed. The older patient thus may present with a fall rather than transient loss of consciousness. There is an increased susceptibility to syncope with advancing age attributed to age-related physiological impairments in heart rate and blood pressure, and alterations in cerebral blood flow. Multi-morbidity and polypharmacy in these complex patients increases susceptibility to syncope. Cardiac causes and more than one possible cause are also common. Syncope is a major cause of morbidity and mortality and is associated with enormous personal and wider health economic costs. In view of this, prompt assessment and early targeted intervention are recommended. The purpose of this article is to update the reader regarding the presentation and management of syncope in this rapidly changing demographic.

Overview of the contribution of recent clinical trials to advancement of syncope management

In this communication we review those trials that have contributed in recent years to improving our knowledge on the management (diagnosis and treatment) of syncope. In this regard, most recent trials focus on vasovagal syncope (VVS) and consequently these will be the focus of this manuscript. In essence, from a diagnostic perspective the ISSUE studies demonstrate the value of insertable loop recorders (ILR), while in terms of treatment, in the case of VVS current data strongly support use of non-pharmacologic treatment as a primary approach. There is no clear evidence supporting pharmacologic treatment with the possible exception of midodrine. Further, the most recent ISSUE trials suggest that in older very symptomatic patients with VVS in whom an asystole has been documented during spontaneous episode or possibly after ATP administration, implantation of a permanent pacemaker (PPM) can be effective. Which pacing or programming mode will be the more beneficial has not been completely clarified. Management of other forms of neurally-mediated syncope (e.g., carotid sinus syndrome) or other causes of syncope has not been addressed by clinical trials. In those cases, direction is provided by older evidence, the vast majority of which is based on observational reports or small non-randomized patient series.

Medical therapy and physical maneuvers in the treatment of the vasovagal syncope and orthostatic hypotension

Patients with vasovagal syncope and neurogenic orthostatic hypotension can both present with pre-syncope and syncope resulting from systemic hypotension. While not directly responsible for increased mortality, both of these conditions can have a tremendous deleterious impact on the daily lives of patients. This negative impact can take the form of both physical symptoms and injury, but also a psychological impact from living in fear of the next syncopal episode. Despite these similarities, these are different disorders with fixed damage to the autonomic nerves in neurogenic orthostatic hypotension, as opposed to a transient reflex hypotension in "neurally mediated" vasovagal syncope. The treatment approaches for both disorders are parallel. The first step is to educate the patient about the pathophysiology and prognosis of their disorder. Next, offending medications should be withdrawn when possible. Non-pharmacological therapies and maneuvers can be used, both in an effort to prevent the symptoms and to prevent syncope at the onset of presyncope. This is all that is required in many patients with vasovagal syncope. If needed, pharmacological options are also available for both vasovagal syncope and neurogenic orthostatic hypotension, many of which are focused on blood volume expansion, increasing cardiac venous return, or pressor agents to increase vascular tone. There is a paucity of high-quality clinical trial data to support the use of these pharmacological agents. We aim to review the literature on these different therapy choices and to give recommendations on tailored approaches to the treatment of these conditions.

[Tilt training increases vasoconstrictor reserve in patients with neurocardiogenic syncope]

Neurocardiogenic syncope (NCS) is a common clinical entity resulting from an excessive reflex autonomic response, particularly during orthostatism. Treatment options are controversial and of limited effectiveness. Tilt training (TT) is a promising option to treat these patients. However, its mechanism of action and clinical impact remain unclear.

OBJECTIVE

To characterize hemodynamic and autonomic responses during a TT program in patients with NCS refractory to conventional measures.

METHODS

We studied 28 patients (50% male, mean age 41±14 years) without structural heart disease, with NCS documented by tilt testing. The TT program included 9 tilt sessions (3 times a week, 30 min) (60° - 6 sessions, 70° - 3 sessions), under ECG and blood pressure monitoring combined with home orthostatic self-training and 10° head-up during sleep. Systolic volume, cardiac output, total peripheral resistance, baroreflex sensitivity and heart-rate variability were computed. Patients were reassessed at 1 month and every 6 months for a maximum of 36 months (24±12 months).

RESULTS

Over the course of the TT program there was a significant increase in total peripheral resistance (1485±225 vs. 1591±187 dyn·s·cm(-5), p<0.05), with a decrease in standard deviation (206±60 vs. 150±42, p<0.05). During follow-up, syncope recurred in five patients (19%), with a significant reduction in the number of episodes (4.0±3.2/patient in the 12 months before TT vs. 1.4±0.8/patient post-TT, p<0.05).

CONCLUSION

In refractory NCS, TT may be an effective therapeutic option, with long-term benefits. These results appear to be due to an increase in vasoconstrictor reserve combined with a reduction in its variance.

Functional capacity is significantly impaired in primary biliary cirrhosis and is related to orthostatic symptoms

OBJECTIVE

To assess patient-reported functional ability and its relationship with symptoms in primary biliary cirrhosis (PBC).

METHODS

Functional status was assessed in a representative cohort of 75 patients with PBC using the Patient-Reported Outcome Measure Information System Health-Assessment Questionnaire (PROMIS-HAQ) functional assessment tool and was related to both symptom severity at the point of assessment (assessed using the PBC-40 and Orthostatic Grading Scale) and symptom severity change over the previous 4 years. Functional status in the PBC group was compared with primary sclerosing cholangitis (cholestatic liver disease) and community controls.

RESULTS

Functional impairment at follow-up (PROMIS-HAQ) was substantial in PBC significantly higher than that in both primary sclerosing cholangitis and community controls. PROMIS-HAQ domain scores confirmed that patients with PBC had significant impairment in arising, eating, walking, reach and grip and activity, but not dressing or hygiene. Functional impairment correlated positively with greater PBC-40 Fatigue, Cognitive and Social and Emotional domains and higher orthostatic symptoms. Over 4 years, total symptom burden increased significantly (P=0.03). The predominant factor was rise in Cognitive domain scores indicating worsening cognitive symptoms (P<0.0001). Change in PBC-40 Cognitive, Social and Emotional scores (2005-2009) strongly predicted functional ability in 2009. Multivariate analysis confirmed that PROMIS-HAQ scores were predicted independently by PBC-40 Social and Emotional scores (P=0.02; β=0.3) and orthostatic symptoms (P=0.04; β=0.3).

CONCLUSION

PBC associates with substantial functional impairment. PBC symptom distribution evolves over time, with cognitive symptoms making ever-greater contribution to overall symptom burden. The major potentially modifiable determinant responsible for the functional impairment appears to be orthostatic symptoms.

[Reflex syncope : diagnosis and therapy]

Reflex-mediated syncope is a common cause for syncope. The first step in evaluating the cause of syncope is to assess the risk of a life-threatening cause for syncope, e.g., ventricular arrhythmias. Reflex-mediated syncope has to be differentiated from orthostatic syncope. In orthostatic syncope, there is an insufficient autonomic response. In contrast to a reflex-mediated syncope, in which the autonomic nervous system acts inappropriately, reflex-mediated syncope is classified into the classical vasovagal form, the situational form, or due to carotid sinus hypersensitivity. In the elderly, often a mixed form is present. Treatment is difficult. Most important is educating the patient and avoiding precipitating factors. Physical maneuvers, e.g., counter pressure maneuvers, are more effective than drug treatment. Permanent pacing is rarely needed. However, before indicating a pacemaker, a correlation between bradycardia and syncope should be documented. This is often only possible by implanting a monitoring device at an early stage.

Orthostatic symptoms predict functional capacity in chronic fatigue syndrome: implications for management

OBJECTIVES

To establish the relationship between the functional impairment experienced by Chronic fatigue syndrome (CFS) patients and the symptoms frequently experienced by those with CFS; specifically cognitive impairment, fatigue and orthostatic symptoms.

DESIGN

Cross sectional questionnaire survey.

SETTING

Specialist CFS Clinical Service.

SUBJECTS

Ninety-nine Fukuda diagnosed CFS and 64-matched controls.

MAIN OUTCOME MEASURES

Symptom and functional assessment tools completed and returned by post included; PROMIS HAQ (Patient-Reported Outcomes Measurement Information System, Health Assessment Questionnaire), CFQ (Cognitive Failures Questionnaire), FIS (Fatigue Impact Scale) and OGS (Orthostatic Grading Scale) assessment tools.

RESULTS

CFS patients experience greater functional impairment than controls [mean (95% CI) PROMIS HAQ scores CFS 36 (31-42) vs. controls 6 (2-10); P < 0.0001], especially in the functional domains of activities and reach. Poorer functional ability impairment is significantly associated with greater cognitive impairment (P = 0.0002, r = 0.4), fatigue (P < 0.0001, r = 0.5) and orthostatic symptoms (P < 0.0001, r = 0.6). However, only orthostatic symptoms (OGS) independently associated with functional impairment (beta = 0.4, P = 0.01).

CONCLUSION

Treatment of orthostatic symptoms in CFS has the potential to improve functional capacity and so improve quality of life.