Syncope Burden Research Articles

Syncope in a Working-Age Population: Recurrence Risk and Related Risk Factors.

Syncope in a worker undertaking risky tasks may result in fatalities for the individual or for third parties. We aimed at assessing the rate of syncope recurrence and the risk factors underlying the likelihood of syncope relapse in a working-age population. A prospective cohort of all patients aged 18–65 years consecutively admitted to the Emergency Department for syncope was enrolled. Risk of syncope relapse was assessed at a six-month, 1-year, and 5-year follow-up. Predictors of syncope recurrence have been evaluated at six months and 1 year from the syncope index by a multivariable logistic regression analysis. 348 patients were enrolled. Risk of syncope relapse was 9.2% at 6 months, 11.8% at 1 year, and 23.4% at 5 years. At 6-month follow-up, predictor of syncope recurrence was ≥3 prior lifetime syncope episodes. At 1-year, ≥3 prior lifetime syncope episodes, diabetes mellitus, and anaemia were risk factors for syncope relapse. There was an exceeding risk of recurrence in the first 6 months and a reduced risk of 3.5% per year after the first year. Anaemia, diabetes mellitus, and prior lifetime syncope burden are of importance when giving advice about the resumption of “high risk” jobs following a syncope episode.

Dual-Chamber Pacing With Closed Loop Stimulation in Recurrent Reflex Vasovagal Syncope: The SPAIN Study

BackgroundPacing in vasovagal syncope remains controversial. ObjectivesThe authors evaluated dual-chamber pacing with closed loop stimulation (DDD-CLS) in patients with cardioinhibitory vasovagal syncope. MethodsThis randomized, double-blind, controlled study included Canadian and Spanish patients age ≥40 years, with high burden syncope (≥5 episodes, ≥2 episodes in the past year), and a cardioinhibitory head-up tilt test (bradycardia <40 beats/min for 10 s or asystole >3 s). Patients were randomized to either DDD-CLS pacing for 12 months followed by sham DDI mode pacing at 30 pulses/min for 12 months (group A), or sham DDI mode for 12 months followed by DDD-CLS pacing for 12 months (group B). Patients in both arms crossed-over after 12 months of follow-up or when a maximum of 3 syncopal episodes occurred within 1 month. ResultsA total of 46 patients completed the protocol; 22 were men (47.8%), and mean age was 56.30 ± 10.63 years. The mean number of previous syncopal episodes was 12 (range 9 to 20). The proportion of patients with ≥50% reduction in the number of syncopal episodes was 72% (95% confidence interval [CI]: 47% to 90%) with DDD-CLS compared with 28% (95% CI: 9.7% to 53.5%) with sham DDI mode (p = 0.017). A total of 4 patients (8.7%) had events during DDD-CLS and 21 (45.7%) during sham DDI (hazard ratio: 6.7; 95% CI: 2.3 to 19.8). Kaplan-Meier curve was significantly different between groups in time to first syncope: 29.2 months (95% CI: 15.3 to 29.2 months) versus 9.3 months (95% CI: 6.21 months, NA; p < 0.016); odds ratio: 0.11 (95% CI: 0.03 to 0.37; p < 0.0001). ConclusionsDDD-CLS pacing significantly reduced syncope burden and time to first recurrence by 7-fold, prolonging time to first syncope recurrence in patients age ≥40 years with head-up tilt test–induced vasovagal syncope compared with sham pacing. (Closed Loop Stimulation for Neuromediated Syncope [SPAIN Study]; NCT01621464)

GENDER DIFFERENCES IN PRESENTATION AND OUTCOME OF VASOVAGAL SYNCOPE: A POST HOC ANALYSIS OF THE PREVENTION OF SYNCOPE TRIALS (POST) I AND II

Vasovagal syncope is the loss of consciousness due to decreased heart rate(HR) and blood pressure(BP) from increased parasympathetic tone and concomitant inhibition of sympathetic outflow. It occurs in >40% of Canadians, however differences in presentation and outcomes between male and female patients are not understood. The Prevention of Syncope Trial (POST) I and II were multicenter randomized controlled trials testing the effectiveness of metoprolol and fludrocortisone, respectively on patients with syncope. We investigated sex-dependent differences in presentation and outcome of vasovagal syncope. We hypothesized that women would suffer a greater burden of syncope and that the triggers for syncopal spells would differ. There were 418 patients with >2 lifetime syncope events, with no significant comorbidities, pacemaker, glaucoma, diabetes, hepatic disease, hypertension or contraindication to the study medications. Data regarding clinical presentation, outcomes and time to first syncopal event after randomization were compared between men and women. χ2 analysis was used for categorical variables and Student t-test for continuous variables; the Wilcoxon rank-sum-test was used to compare median values. Survival analysis was performed using the Kaplan Meier method and the log-rank test for significance. A Cox proportional hazards model was used to perform multivariate analysis for time to syncope. There were 280 women (67%) and 138 men (33%). Baseline systolic BP was lower in women (117 vs 124mmHg, p < 0.001) while baseline HR was higher in women (71 vs 69 bpm, p=0.01). Men were older at the time of randomization (42 vs 35, p < 0.0001). Women were younger at the time of the first syncope event (20.5 vs 26.1 years p=0.0009); women had more median lifetime episodes than men (14.5 vs 8.0; p < 0.0001). Syncope due to venipuncture was a more common trigger in men (5% vs 0%, p=0.02), while response to heat was more common in women (65.7% vs 50%, p=0.01). Clinical presentation in women consisted more commonly of feeling warm, having a seizure and having palpitations, as opposed to men (49.1% vs 40.5% p=0.05, 10.5% vs 2.7% p=0.01, 15.4% vs 9.1% p < 0.05, respectively). Post-syncope fatigue was more common in women (53.0% vs 40.6%, p =0.04). After randomization, men were less likely to experience recurrent syncope, after adjustment for pre-randomization syncope burden in the last 12 months and randomization assignment (active treatment vs placebo) (HR 0.64 95% CI 0.45,0.91 p=0.0117) (See Figure). Clinical presentation and triggers of vasovagal syncope differ between men and women, as do recurrent events.

Childhood trauma and lifetime syncope burden among older adults

ObjectiveVasovagal syncope is governed by the autonomic nervous system and often precipitated by highly salient emotional situations. We hypothesized that a lifetime tendency towards vasovagal syncope may be precipitated by exposure to childhood trauma. MethodsWe examined data from the first wave of The Irish Longitudinal Study on Ageing (TILDA) of adults aged 50+ (n=6497) who were asked to report lifetime syncope frequency and any history of childhood sexual or physical abuse. Mediation analysis was used to assess the relative importance of pathways via which childhood trauma could plausibly increase risk of later life recurrent syncope including via depression, mid-life cardiovascular disease and frequent syncope in youth. Results18.2% reported a lifetime syncopal event: 4.0% frequent syncope in youth and 1.5% recurrent syncope in the last year. 10.9% reported childhood sexual or physical abuse, rising to 14.2% among those reporting any lifetime syncopal event, 21.0% with frequent syncope in youth and 20.2% with recurrent syncope in later life. In fully adjusted logistic regression models the report of childhood sexual or physical abuse was independently associated with frequent syncope in youth (OR 1.85 (CI 95% 1.27–2.71); p=0.001; OR 2.14 (1.48–3.10); p<0.001 respectively). A history of frequent syncope in youth and depression partially mediated the relationship between childhood sexual and physical abuse and recurrent syncope in later life, while mid-life cardiovascular disease was less important. ConclusionChildhood trauma may contribute to a lifelong vasovagal tendency. Early attention should be given to the potential precipitating and perpetuating psychosocial factors affecting recurrent syncope.

Syncope in the Pediatric Emergency Department – Can We Predict Cardiac Disease Based on History Alone?

BackgroundThe American Heart Association recommends a “meticulous history” when evaluating patients with an initial episode of syncope. However, little is known about which historical features are most helpful in identifying children with undiagnosed cardiac syncope. ObjectivesOur objectives were 1) to describe the cardiac disease burden in Emergency Department (ED) syncope presentations, and 2) to identify which historical features are associated with a cardiac diagnosis. MethodsUsing syncope presentations in our ED between May 1, 2009 and February 28, 2013, we 1) performed a cross-sectional study describing the burden of cardiac syncope, and 2) determined the sensitivity and specificity of four historical features identifying cardiac syncope. ResultsOf 3445 patients, 44.5% were male presenting at 11.5 ± 4.5 years of age. Of patients with a cardiac diagnosis (68, ∼2%), only 3 (0.09%) were noted to have a previously undiagnosed cardiac cause of syncope: 2 with supraventricular tachycardia and 1 with myocarditis. Among the three cases and 100 randomly selected controls, the respective sensitivity and specificity of the historical features were 67% and 100% for syncope with exercise, 100% and 98% for syncope preceded by palpitations, and 67% and 70% for syncope without prodrome. The presence of at least two features yielded a sensitivity of 100% and specificity of 100%. ConclusionsOur study, which represents the largest published series of pediatric syncope presenting to the ED, confirms that newly diagnosed cardiac causes of syncope are rare. Using a few specific historical features on initial interview can help guide further work-up more precisely.

Recent syncope and unexplained falls are associated with poor cognitive performance.

To compare cognitive performance in participants with and without syncope and unexplained falls in a large population representative sample aged 50 years or older. Participants of the Irish longitudinal study on ageing (TILDA) were studied. Participants with a history of syncope and/or unexplained falls in the past 12 months were compared with those with no reported events. Cognitive performance was measured using the Montreal cognitive assessment (MoCA) score. Multivariate linear regression analysis controlling for potential confounders was performed to compare cognitive function by syncope and falls status. Five thousand eight hundred and forty-six participants were analysed, median age 62 years (inter-quartile range=14), and 54% were female. Five hundred and forty-nine (9.4%) had a syncopal event and/or an unexplained fall in past 12 months. One hundred and two (1.8%) subjects had two-plus syncopal events in the same period. There was a significant association between syncope/falls history and lower MoCA score, following adjustment for all confounders (B=-0.4; -0.69, -0.11; P=0.006). Higher syncope burden was also associated with lower performance; however, this was largely explained by confounders. There was no age interaction with these findings. Participants who experienced syncope and/or non-accidental falls in the previous year have poor global cognitive performance compared with case-controls. There was no effect of age on our results. Further investigation of the association between syncope burden, unexplained falls and cognitive decline is required to establish a relationship between these disorders.

The Cost Burden Of Syncope At A Hospital Level In Spain.

The Cost Burden Of Syncope At A Hospital Level In Spain.

The effect of late adoption of Canadian innovations: A case for implantable cardiac monitors

Syncope is a sudden and generally momentary loss of consciousness, which can have serious adverse events. The outcomes of the syncope episode can vary from a fall to fatal accidents. Syncope has a major negative effect on the patient’s health-related quality of life. The economic burden of syncope on healthcare systems is considerable. There are no clear diagnostic pathways for identifying the cause of syncope; patients can be admitted to hospital and undergo expensive and often repeated and inconclusive diagnostic tests. Implantable cardiac monitors have been available for more than a decade to help early diagnosis of syncope in unexplained cases. However, despite being a Canadian invention, the use of the implantable cardiac monitors has been suboptimal in the Canadian healthcare system. This study provides an overview of syncope, its management, and presents the estimated potential cost savings per diagnosis of systematic use of implantable cardiac monitors in Ontario.

Abstract 18469: Syncope in the Pediatric Emergency Department - Can We Predict Cardiac Disease Based on History Alone?

Objective: The AHA published a statement on the evaluation of syncope in 2006 which stated that a "meticulous history" is of paramount importance when evaluating patients with an initial episode of syncope. However, little is known about which features of the history are most helpful in identifying children with undiagnosed cardiac syncope. Our objective was 1) to describe in a pediatric ED the burden of syncope due to cardiac disease and 2) to identify the historical features which are associated with an underlying cardiac diagnosis. We hypothesized that patients with cardiac syncope would present with at least two of the following four historical features: syncope with exercise, syncope preceded by palpitations, syncope without prodrome, or syncope with exercise preceded by chest pain. Methods: Using a cohort of patients who presented with syncope to our pediatric ED between May 1, 2009 and February 28, 2013, we 1) performed a cross-sectional study to describe the burden of cardiac syncope and 2) determined the sensitivity and specificity of our identified historical features with regard to identifying patients with cardiac syncope. Results: Of 3624 patients, 43.3% were male presenting at a mean age of 12.7 +/- 7.3 years. Of 67 (1.8%) with a cardiac diagnosis, 52 were previously known. Of the 15 new cardiac diagnoses, 12 were considered incidental. Three patients (0.11%) had a newly confirmed cardiac cause of syncope; two with supraventricular tachycardia and one with myocarditis. Among the three cases of cardiac syncope and 50 randomly selected cases of non-cardiac syncope, the respective sensitivity and specificity of the historical features were 67% and 100% for syncope with exercise, 100% and 98% for syncope preceded by palpitations, 67% and 70% for syncope without prodrome, and 67% and 100% for chest pain preceding syncope. Using the presence of at least 2 of the features as a marker for cardiac syncope yielded a sensitivity of 100% and specificity of 100%. Conclusions: Our study represents the largest series of pediatric patients presenting with syncope to an ED and our data confirms that newly diagnosed cardiac causes of syncope are rare. Furthermore, use of a few specific historical features on initial interview can help guide further workup more precisely.

Higher syncope burden is associated with poor cognitive function in an older adult population study

Higher syncope burden is associated with poor cognitive function in an older adult population study

PMD38 The Cost Burden of Unexplained Syncope in Five European Countries: A Database Analysis

PMD38 The Cost Burden of Unexplained Syncope in Five European Countries: A Database Analysis

Correlation of syncopal burden with anxiety symptoms score in recurrent vasovagal syncope

Vasovagal syncope (VVS) is the transitory loss of consciousness secondary to generalized cerebral hypoperfusion due to arterial hypotension with or without a concomitant reduction of heart rate [1]. Subjects suffering from recurrent VVS can have a high psychological stress including anxiety, depression, concern, and somatic complaints [2,3]. In previous studies, syncopal burden has been inversely correlated with quality of life but no significant correlation was observed between anxiety, depression and the patient's syncopal burden [2,3]. The aim of this study was to correlate syncopal burden with symptoms score of anxiety and depression in subjects with VVS and no psychiatric disorders. The study included 51 patients (27 females, median age 17 years, age range 15 to 45 years old) attending a syncope unit. All patients were evaluated by an expert physician. Diagnosis was established in the presence of a clinical history characteristic of VVS (simple fainting of very brief duration that occurs with the subject standing or at the moment of stand-up) with one or more of the following prodromal symptoms: dizziness, pallor, visual blurring, diaphoresis, dysesthesia, sighing dyspnea, tremor in fingers, or nausea [4,5]. All participants filled out the Beck Depression Inventory (BDI), the Beck Anxiety Inventory (BAI) and a cognitive function test [6–8]. Syncopal burden was classified as follows: low burden (≤3 events in the last 6 months), high syncopal burden (N3 events). No significant differences were observed in cognitive function and educational grade among subjects with high or low syncopal burden (data not shown). Exclusion criteria were: orthostatic hypotension, suspected or confirmed heart disease, other specific causes of neurally mediated syncope (situational or associated to coughing, swallowing or brisk neck movements), metabolic or neurological disorders, any concurrent disease or treatment that affects the autonomic nervous system, or knownpsychiatric disorder. All subjects gave informed written consent to participate. The study complies with the ethical guidelines of the 1975 Declaration of Helsinki, as well as the standards established by the Ethics Committee of the Instituto Nacional de Cardiologia Ignacio Chavez. The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology. Results are shown in Table 1. In the total study group, anxiety symptoms were present in 17 patients (33%), and depression symptoms in 23 subjects (45%). Anxiety symptoms score was directly associated with the syncopal burden: patients with high syncopal burden had a higher anxiety score than subjects with low syncopal burden. No significant differences were observed in gender or depression symptoms score among subjects with high or low syncopal burden. It is clinically relevant to correctly discriminate anxiety related to VVS from anxiety as a part of a psychopathology that will need, by itself, specific treatment. Subjects with a psychiatric disorder usually do not respond to conventional treatment of VVS, have a higher severity of syncope, more prodromal symptoms and higher recurrence of syncope thanpatients without a psychiatric illness [9]. On the other hand, subjects without psychopathology can develop anxiety related to recurrence of VVS. In them, anxietymay be the result, not the cause of VVS and could be solved by avoiding the recurrence of the events. Our finding of higher levels of anxiety, but not depression, in subjects with VVS and a higher syncopal burden is relevant for two reasons: (1) it supports the hypothesis of a bidirectional relationship between cognitive/affective factors and syncopal symptoms in subjects with VVS [10], and (2) because, as suggested bymany investigators, the diagnosis and treatment of these minor psychiatric disorders may be crucial for the effective treatment of VVS. The subgroup of patients with a high syncopal burden could be the most benefited by early intervention aimed to acquire skills for functional coping with their distressing symptoms. Also relevant, the present finding could explain the reported benefit of clonazepam, a drug with anxiolytic effects, in subjects with VVS [11,12]. In conclusion, higher levels of anxiety were observed in subjects with a clinical diagnosis of VVS and a high recurrence of syncopal episodes, supporting a bidirectional relationship between cognitive/affective factors and syncopal symptoms in VVS. The authors thank Alma Delia Ferreira Vidal for her assistance during the recruitment of participants, and Ms Betty Lou Chin R.N. for her support in the preparation of the manuscript.

A standardized education protocol significantly reduces traumatic injuries and syncope recurrence: an observational study in 316 patients with vasovagal syncope

The aim of this study was to assess the role of a non-pharmacological approach on the frequency of traumatic injuries and syncope recurrence in patients with vasovagal syncope and normal hearts. We report the experience in our syncope centre with a standardized education and teaching protocol for patients with vasovagal syncope. The treatment of vasovagal syncope is often complex and discouraging. Besides medical options, behaviour modification is a main component of therapy but has no statistical evidence to support its use. Between January 1999 and September 2006, we prospectively enrolled all patients with vasovagal syncope. The patients were counselled about the benign nature of their disease. Specific recommendations were made according to a standardized education protocol established at our syncope centre. A pre-/post-study was conducted to investigate the effectiveness of our approach on syncope recurrence and frequency of injury as the study endpoints. Complete follow-up data were available from 85% of the study population (316 of 371) after a mean time of 710 ± 286 days (mean age 50 years; standard deviation ± 18 years, 160 female). Eighty-seven patients (27.5%) had a syncope recurrence with 22 suffering an injury during syncope. During the follow-up period, the syncope burden per month was significantly reduced from 0.35 ± 0.03 at initial presentation to 0.08 ± 0.02 (P< 0.001). The frequency of traumatic syncope was significantly lower at the time of recurrence compared with the initial presentation (25 vs. 42%; McNemar's test P= 0.02). A standardized education protocol significantly reduces traumatic injuries and syncope recurrence in patients with vasovagal syncope.

Recent History of Vasovagal Syncope in a Young, Referral‐Based Population Is a Stronger Predictor of Recurrent Syncope Than Lifetime Syncope Burden

accurate selection of patients for vasovagal syncope studies requires strong risk stratification and knowledge of the natural history of syncope. We aimed to test the hypothesis that recent history of vasovagal syncope compared to distant history better predicts subsequent recurrence of syncope. in all, 208 subjects with a positive tilt test and ≥ 3 lifetime syncope spells were followed for 1 year. Syncope episodes in the preceding year and total historical spells were compared for their ability to predict a syncope recurrence using the criteria of optimal statistical significance, best linear separation of risk populations, and impact on power calculations. The number of vasovagal syncope spells in the preceding year better predicted syncope recurrence when compared to total number of historical spells (likelihood ratio statistic 28.4, P < 0.0001; versus 20.4, P = 0.001), and showed a substantial effect as the number of syncope events increased. For example, syncope recurred in 22% of those with <2 spells in the previous year compared to 69% in those with >6 spells. A history of no syncope compared to any syncope in the preceding year was associated with a 1-year probability of 7% versus 46% for syncope recurrence. A study designed to detect a 50% decrease in syncope recurrence at P = 0.05 with 80% power would require 159 patients with at least 3 lifetime spells, and only 108 patients with at least 3 spells in the previous year. the number of syncope events in the year preceding clinical evaluation is the best predictor of syncope recurrence.

The clinical relevance of the duration of loss of consciousness provoked by tilt testing

Objective — The authors assessed the relationships between the duration of loss of consciousness (dLOC) during tilt testing-induced syncope (TTS) and demographics, medical history as well as tilt testing results. Previous research focused on the relevance of the type of neurocardiogenic reaction during TTS. The importance of dLOC has not been assessed so far. The study was carried out in 274 patients with suspected neurally mediated syncope and total loss of consciousness during tilt testing.Results — The syncope burden, demographics, and data regarding spontaneous syncope or TTS were compared between group 1 with dLOC ≥ 47 seconds and group 2 with dLOC < 47 seconds. Medical history revealed that patients in group 1 had more syncopal spells, more frequent syncope-related traumatic injuries, urine incontinence, jerking movements and typical vasovagal history than in group 2. Moreover, group 1 patients had more frequently a cardioinhibitory type of reaction and a shorter active phase duration. In addition, they manifested more frequent accompanying cerebral hypoperfusion signs and reproduction of symptoms during TTS than patients in group 2.Conclusions — The loss of consciousness during tilt testing-induced syncope differs in terms of duration among patients with neurally mediated syncope.The dLOC during TTS is associated with medical history and tilt-testing data which confirm the vasovagal aetiology of spontaneous events. The longer dLOC suggests deeper cerebral haemodynamic disturbances during either spontaneous or provoked syncope.

Prospective evaluation of non-pharmacological treatment in vasovagal syncope

Initial treatment of vasovagal syncope (VVS) consists of assuring an adequate fluid and salt intake, regular exercise and application of physical counterpressure manoeuvres. We examined the effects of this non-pharmacological treatment in patients with frequent recurrences. One hundred patients with > or =3 episodes of VVS in the 2 years prior to the start of the study openly received non-pharmacological treatment. We evaluated this treatment both with respect to syncopal recurrences, factors associated with recurrence, and quality of life (QoL). The median number of syncopal recurrences was lower in the first year of non-pharmacological treatment compared with the last year before treatment (median 0 vs. 3; P < 0.001), but 49% of patients experienced at least one recurrence. In multivariable analysis, a higher syncope burden prior to inclusion was significantly associated with syncopal recurrence. Disease-specific QoL improved over time, with larger improvements for patients with more reduction in syncope burden. In patients with frequent recurrences of VVS, non-pharmacological treatment has a beneficial effect on both syncopal recurrence and QoL, but nearly half of these patients still experience episodes of syncope.

Preliminary observations on the use of closed-loop cardiac pacing in patients with refractory neurocardiogenic syncope

In many patients with recurrent neurocardiogenic syncope (NCS), a significant fall in blood pressure precedes any appreciable decline in heart rate. Closed-loop pacing (CLS) employs a sensing system that measures myocardial contractility, thereby providing a potential way to detect the onset of NCS at a much earlier point in time than that provided by standard pacing systems. Patients were included in the study if they suffered from recurrent NCS and met all of the following criteria: (1) They had suffered at least two syncopal episodes in the preceding 6 months. (2) Patients were refractory to (or intolerant of) all conventional, non-pharmacological, or pharmacological treatments. (3) They had evidence of asystole (>10 s) or severe bradycardia (heart rate <30 bpm) on implantable loop recorder or during head-up tilt test (HUTT). Thirty five patients meeting the above criterion received 44 devices. Twelve patients received a standard unit (with rate drop or rate hysterisis response) and 32 patients received a CLS unit (Cylos, Biotronik). The pacemaker implantation was termed successful if there was no recurrence of syncope, if the syncope burden decreased by > or =50%, if only presyncope occurred, or if the syncope occurred but with significant warning symptoms. Thirty-five patients, 29 females and six males, age 41 +/- 11, with refractory NCS underwent pacemaker implantation. Mean follow-up was 9 +/- 3 months. Out of 32 patients who received CLS, nine had a conventional pacemaker implanted in the past. Recurrence (59% vs 83%), reduction in syncope burden and pacemaker success (84% vs 25%, P = 0.002), and occurrence prodrome/warning signs (40% vs 16%) were much better in the closed-loop group. These preliminary observations suggest that dual-chamber CLS pacing may be promising therapy for refractory NCS. Further randomized trials will be needed to better determine the role of this therapy in refractory NCS.

Clinical relevance of syncope and presyncope induced by tilt testing

Objective — The authors investigated the relation between presyncope and syncope induced by tilt testing (HUTT) and demographics, medical history and HUTT data.The demographics, syncopal burden, data regarding the spontaneous syncope and reproduction of symptoms during HUTT were compared among patients with induced syncope and presyncope. The study group consisted of 574 patients (371 women, 203 men), aged 43.7 ± 18.5 years.Methods and results — Patients with syncope induced by HUTT (418 patients, 63.9% women) had a higher number of syncopal episodes in their medical history. Stepwise logistic regression revealed that syncope provocation was independently related to the cardiodepressive type of neuro-cardiogenic reaction (OR 7.8, CI 4.2-14.4, P < 0.001), NTG use (OR 1.7, CI: 1.0-2.7, P < 0.05), the reproduction of the symptoms during HUTT (OR 2.0, CI: 1.3-3.1, P < 0.01) and the higher number of syncopal episodes (OR 2.0, CI: 1.3-3.0, P < 0.01). In patients with positive HUTT during a passive phase it was related to the cardiodepressive type of reaction (OR 26.5, CI: 5.9-118.5, P < 0.001). In the group with positive HUTT after NTG syncope was related to the cardiodepressive type (OR 5.7, CI: 2.9-11.2, P < 0.001), vasovagal history (OR 2.0, CI: 1.2-3.3, P < 0.01), reproduction of the spontaneous symptoms (OR 1.9, CI: 1.1-3.1, P < 0.05) and higher number of syncopal episodes (OR 2.1, CI: 1.3-3.3, P < 0.01).Conclusions — Syncope is more frequently a HUTT outcome than presyncope.The provocation of syncope in the passive phase of HUTT depends only on the cardiodepressive type of neuro-cardiogenic reaction. The induction of presyncope after nitroglycerin provocation is related to the possibility of a false positive reaction.

Cardioinhibitory carotid sinus hypersensitivity predicts an asystolic mechanism of spontaneous neurally mediated syncope

We correlated the finding of cardioinhibitory carotid sinus hypersensitivity (CSH) with that observed during a spontaneous syncopal relapse by means of an implantable loop recorder (ILR). We included 18 consecutive patients with suspected recurrent neurally mediated syncope and positive cardioinhibitory response during carotid sinus massage (max pause 5.5 +/- 1.6 s) who had subsequent documentation of a spontaneous syncope by means of an ILR. They were compared with a 2:1 age- and sex-matched group of 36 patients with a clinical diagnosis of recurrent neurally mediated syncope and negative response to carotid sinus massage, tilt testing and ATP test. Asystole >3 s was observed at the time of the spontaneous syncope in 16 (89%) of CSH patients and in 18 (50%) of the control group (P = 0.007). Sinus arrest was the most frequent finding among CSH patients but not among controls (72 vs. 28%, P = 0.003). After ILR documentation, 14 CSH patients with asystole received dual-chamber pacemaker implantation; during 35 +/- 22 months of follow-up, 2 syncopal episodes recurred in 2 patients (14%), and pre-syncope occurred in another 2 patients (14%). Syncope burden decreased from 1.68 (95% confidence interval 1.66 - 1.70) episodes per patient per year before to 0.04 (0.038-0.042) after pacemaker implant (98% relative risk reduction). In patients with suspected neurally mediated syncope, the finding of cardioinhibitory CSH predicts an asystolic mechanism at the time of spontaneous syncope and, consequently, suggests a possible benefit of cardiac pacing therapy.

Full Length Article

In this study, we assessed the effectiveness of physical counterpressure maneuvers (PCM) in daily life. There is presently no evidence-based therapy for vasovagal syncope. Current treatment consists of explanation and life-style advice. Physical counterpressure maneuvers have been shown to raise blood pressure and to control or abort vasovagal episodes in laboratory conditions. We performed a multicenter, prospective, randomized clinical trial, which included 223 patients age 38.6 (±15.4) years with recurrent vasovagal syncope and recognizable prodromal symptoms. One hundred and seventeen patients were randomized to standardized conventional therapy alone, and 106 patients received conventional therapy plus training in PCM. The median yearly syncope burden during follow-up was significantly lower in the group trained in PCM than in the control group (p = 0.004). During a mean follow-up period of 14 months, overall 50.9% of the patients with conventional treatment and 31.6% of the patients trained in PCM experienced a syncopal recurrence (p = 0.005). Actuarial recurrence-free survival was better in the treatment group (log-rank p = 0.018), resulting in a relative risk reduction of 39% (95% confidence interval, 11% to 53%). No adverse events were reported. Physical counterpressure maneuvers are a risk-free, effective, and low-cost treatment method in patients with vasovagal syncope and recognizable prodromal symptoms, and should be advised as first-line treatment in patients presenting with vasovagal syncope with prodromal symptoms. (The PC-Trial; http://www.controlled-trials.com/isrctn/trial/45146526/0/45146526.html; ISRCTN45146526)