Long-term outcome of patients with vasovagal syncope

Background

After abnormal head-up tilt test (HUT), several trials have evaluated treatment strategies for vasovagal syncope (VVS). However, few unequivocal results have been obtained. The aim of the study was to prospectively analyze the natural history of patients with VVS who did not undergo specific treatment but received education for avoiding syncope after an abnormal HUT.

Methods

From 1996, 334 consecutive patients with VVS and an abnormal HUT result were followed. All of them received education for avoiding syncope as first-line therapy.

Results

During 30.4 ± 21 months, there were no cardiac deaths. However, 101 patients (30.2%) had recurrences (1 recurrence, n = 64; ≥2, n = 37), which were not influenced by the type of response during HUT or by age. Time to first recurrence was correlated with the number of recurrences (r: −0.34, P = .0001). Mean recurrence-free time was 50.1 months (95% CI 46-54) and the cumulative probability of no recurrence was 69.8%. Receiver operator character curve analysis, demonstrated significant differences in the recurrence rate between patients with <5 or ≥5 previous episodes of syncope (25.1% vs 44%; P = .001). In addition, the mean recurrence-free time of patients with <5 episodes was significantly longer (54.1 months) than in patients with ≥5 episodes (39.6 months; P = .0005). Multivariate logistic regression identified the previous number of episodes as an independent risk marker of recurrences (odds ratio 2.34, 95% CI 1.4-3.8, P = .001). Age (at HUT performance) as a continuous variable was not a predictor of outcome.

Conclusions

Survival of patients with VVS presenting after an abnormal HUT is excellent. Although the broad majority of those patients do not suffer recurrences after education, the number of previous syncopal episodes critically influences the recurrence rate.     

Electrophysiologic evaluation and outcome of patients with syncope of unknown origin

Electrophysiologic studies were performed in 134 patients (87 males, mean age 59 years) with unexplained syncope. Seventy-one patients had organic heart disease (ischaemic in 50). Electrophysiologic studies revealed conduction abnormalities and tachyarrhythmias that could account for syncope in 40 patients (30%). Thirty-seven (93%) of these patients received pacing or antiarrhythmic therapy compared with 23 (24%) of the remaining 94 patients who had a negative study and received empiric therapy (P less than 0.0001). Risk of having an abnormal electrophysiologic study was greater in patients with underlying heart disease (P less than 0.05). During a mean follow-up of 22 +/- 17 months, 26 patients (19%) either had recurrent syncope (22 patients) or died (four patients) suddenly. Men had a higher incidence of recurrent syncope than women (26% vs 6%, P less than 0.005). Other clinical characteristics, electrophysiologic findings, final diagnosis and therapy at discharge were not predictive of outcome. We conclude that (1) 19% of patients investigated for syncope will have a recurrent event, (2) female gender may be an independent predictor of favourable outcome.     

Evaluation of prognostic classifications for patients with syncope

To evaluate two published sets of prognostic classifications for patients with syncope, 176 consecutive patients who presented to an emergency room with syncope were studied. Although relatively few patients had cardiac syncope, these data confirmed their high one-year mortality. At the other extreme, it was also confirmed that patients who were 30 years of age or less or 70 years of age or less and had vasovagal/psychogenic syncope or syncope of unknown cause had a benign prognosis, with only two deaths in 225 patients in pooled data. However, these data did not confirm the previously reported prognoses for "medium-risk patients" or for patients with diagnosable noncardiovascular causes of syncope, largely because of differences in criteria for patient eligibility. It is concluded that available data allow over 70 percent of patients with syncope to be placed into either very-high or very-low-risk groups. However, further investigation, taking into account differences in patient selection criteria, will be required before accurate prognostic classifications can be derived for the nearly 30 percent of patients who do not fall into one of these extreme prognostic categories.     

177例血管迷走性晕厥的临床特征及治疗转归

目的对血管迷走性晕厥(VVS)患者的临床特征及治疗转归进行总结。方法 177例患者经倾斜试验确诊为VVS,对其VVS的类型、年龄段分类、发作晕厥的症状和体征、不同季节发生情况以及治疗转归进行统计。结果血管抑制型56例、心脏抑制型6例、混合抑制型115例,分别占31.6%、3.4%、65.0%。所有患者在晕厥发生前均有心率突然增快,继之突然下降的过程,可表现为窦性心动过缓、心脏停搏等心率缓慢的症状。倾斜试验阳性与季节似乎无关。年龄在40～59岁之间的人群中VVS发生较高。β受体阻滞剂治疗VVS有效。结论 VVS可能是自主神经失调所致,β受体阻滞剂抗交感治疗有效。     

Evaluation of syncope in geriatric patients: normal values, complications and outcome of invasive electrophysiological study

Invasive electrophysiologic study (EPS) is an important tool in the assessment of patients with unexplained syncope. Especially in the elderly, the need for a complete diagnostic work-up is counterbalanced by the fear of complications associated with invasive procedures. Thus, the present study specifically addressed the question whether the risk/benefit ratio of EPS in geriatric patients with unexplained syncope justifies this invasive procedure. An invasive EPS was performed in 96 patients between 70 and 80 years and 21 patients older than 80 years. The control group consisted of 65 patients younger than 40 years. With increasing age, the diagnostic yield of EPS also increased (positive EPS finding in 20% of the control group and in 54% of the oldest patients). The majority of complications were of minor clinical significance and no significant differences were found between the three groups. Finally, no age-related difference in measured standard electrophysiological parameters was evident. Due to the high diagnostic value and the low complication rate, EPS can be recommended in elderly patients with unexplained syncope. An age-specific standardization of electrophysiologic parameters, measured during EPS, does not seem to be required.     

Electrophysiologic testing in patients with unexplained syncope: clinical and noninvasive predictors of outcome

To assess whether the level of risk of having significant electrophysiologic abnormalities can be determined, 29 clinical variables were analyzed in 104 patients with unexplained syncope who underwent electrophysiologic testing. A positive electrophysiologic study was defined as: a sinus node recovery time greater than or equal to 3 seconds; HV interval greater than or equal to 100 ms; infranodal block during atrial pacing; unimorphic ventricular tachycardia; and supraventricular tachycardia associated with hypotension. Thirty-one patients had a positive study, with inducible ventricular tachycardia being the most common finding (71% of positive studies). A left ventricular ejection fraction less than or equal to 0.40 was the most powerful predictor of a positive electrophysiologic study (p less than 0.00001), followed by the presence of bundle branch block (p less than 0.00003), coronary artery disease (p less than 0.0003), remote myocardial infarction (p less than 0.00006), use of type 1 antiarrhythmic drugs (p less than 0.00003), injury related to loss of consciousness (p less than 0.01) and male sex (p less than 0.01). A negative electrophysiologic study was associated with an ejection fraction greater than 0.40 (p less than 0.00001), the absence of structural heart disease (p less than 0.00001), a normal electrocardiogram (ECG) (p less than 0.0001) and normal ambulatory ECG monitoring (p less than 0.0001). The probability of a negative study increased as the number and duration of syncopal episodes increased.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term outcome of patients with syncope associated with coronary artery disease and a nondiagnostic electrophysiologic evaluation

Syncope in the patient with structural heart disease and a nondiagnostic noninvasive workup is a generally accepted indication for an invasive electrophysiologic study. However, if the electrophysiologic evaluation is not highly sensitive, arrhythmic causes of syncope may not be discovered. In these patients, recurrent syncope and even sudden death may be observed at follow-up. Thus, we evaluated long-term follow-up in 68 consecutive patients who presented with syncope, coronary artery disease, and who had a negative invasive electrophysiologic evaluation. At a mean follow-up of 30 +/- 18 months (range 1 to 65), there have been 2 sudden deaths and 1 episode each of ventricular fibrillation and ventricular tachycardia in patients treated with an implantable cardioverter-defibrillator. All 4 arrhythmias occurred in patients with left ventricular fractions < or = 25%. Seventeen patients had recurrent presyncope or syncope. Bradycardia causing syncope was found in 8 of these patients. A bundle branch block at the initial evaluation predicted for the occurrence of bradycardia at follow-up. We conclude that in patients with coronary artery disease and syncope, noninducibility at electrophysiologic study predicts a lower risk of sudden death and ventricular arrhythmias. However, in patients with a reduced ejection fraction, the risk of sudden death and ventricular arrhythmias remains up to 10%/year and these patients may warrant treatment with implantable cardioverter-defibrillators. Recurrent syncope is common, and frequently a bradyarrhythmia is found to be the cause. Treatment of selected patients (especially those with bundle branch blocks) with permanent pacemakers may be justified.     

Evaluation of the patient with syncope

Evaluation of the patient who has experienced spontaneous, transient loss of consciousness requires a comprehensive consideration of many disease etiologies. Syncope may be a relatively benign condition with a good prognosis or may be a precursor of subsequent cardiac arrest and sudden death. In this article, the cardiovascular causes of syncope and the role of electrophysiologic testing in the diagnostic evaluation of patients with syncope are discussed.     

Evaluation of syncope

Syncope is not an uncommon condition. The evaluation can be as frustrating as the treatment. The role of a detailed history and physical examination cannot be underestimated and both remain a cornerstone in the evaluation of syncope. A systematic approach may not only lead to correct diagnosis in most cases, but also ultimately will be cost effective. This review emphasizes the systematic approach for the evaluation of this challenging problem.     

Evaluation and management of syncope

The history and physical examination still provide the best basis for the initial evaluation of syncope. In addition to revealing the possibility of a serious--even life-threatening--condition, they also point the way for specific testing.     

Evaluation and management of syncope

Syncope is a common symptom and accounts for approximately 1% of all emergency visits. There are four main causes of syncope: reflex, neurally mediated syncope, orthostatic hypotension and cardiac syncope. The prognosis of patients with reflex syncopes is good, whereas patients with cardiac syncope are at increased risk for sudden cardiac death. The first diagnosic step after transient loss of consciousness the diagnosis syncope has to be established. It has to be differentiated from other forms of loss of consciousness according to current definition. Careful evaluation of the patient with syncope is mandatory. If the underlying cause of syncope can be diagnosed during initial evaluation, the patient should be treated accordingly. If the cause of syncope remains unclear, the patient has to be stratified with respect to the risk of a cardiovascular event and sudden cardiac death and further evaluation initiated. This review gives a comprehensive summary of definition, work-up and treatment of syncope based on the current guidelines for the evaluation of syncope.     

Evaluating elderly patients with syncope

Age-related physiologic changes together with high prevalence of chronic illness and the use of multiple medications predispose older adults to syncope. The causes of many of these patients' syncope are unexplained and most remained symptomatic. A thoughtful diagnostic strategy is essential to pinpoint the cause in each patient. The initial assessment includes a comprehensive medical history, preferably with an eye witness account, and a thorough physical examination. The decision for further diagnostic tests often depends on whether there is evidence of underlying structural heart disease. In the absence of heart disease, tilt table testing and the related autonomic function testing are usually most productive. Various cardiac studies will be more appropriate for those with suspected structural heart disease. A cause of syncope can only be concluded if there is a sufficiently strong correlation between syncopal symptoms and the detected abnormalities on investigations. A strategic evaluation of syncope of the elderly subjects should allow a correct diagnosis and appropriate management.     

Effects of therapy based on tilt testing results on the long-term outcome in patients with syncope

BACKGROUND: The use of tilt testing (TT) in guiding therapy in patients with syncope remains controversial. AIM: To assess the long-term effectiveness of TT-based therapy in patients with syncope of unknown origin. METHODS: The study group consisted of 340 patients (182 females, mean age 38.2+/-16.5 years, range 15-78 years) with at least two syncopal episodes during 6 months preceding the study. TT was performed at 60 degrees angle for 20 min, followed by sublingual nitroglycerine (NTG) challenge (250 microg) when necessary. After positive baseline TT and returning to supine position, 0.1 mg/kg of propranolol was intravenously administered and a second TT was performed. All patients with positive TT were advised to take propranolol, midodrine or fludrocortisone for 6 months -- the choice of agent was based on standard criteria. The time to first syncope was an indicator of the efficacy of treatment and a recurrence of syncope was the end-point of the study. In patients who did not faint during follow-up, the last date of contact was taken as the end of observation period. RESULTS: Out of 340 patients who underwent TT, 148 with positive TT and propranolol challenge were included in the study; 82 patients (group I) received long-term therapy whereas 66 did not (group II). During a 12.8+/-0.9 month follow-up, syncope recurred in 86 patients - 40 (49%) from group I and 46 (70%) from group II (p<0.01). Survival analysis showed that medical therapy was associated with a significant reduction of the risk of syncope recurrence (RRR: 36%, 95% CI: 23-47). The greatest benefit from long-term treatment was documented in patients taking propranolol (RRR: 42%; 95% CI: 18-58; p<0.008), particularly in those in whom intravenous propranolol prevented TT-induced syncope (RRR: 50%; 95% CI: 23-67; p<0.012). Risk reduction in patients treated with midodrine or fludrocortisone was moderate (RRR: 22%; 95% CI: 11-34; p>0.09). CONCLUSIONS: Carefully selected and TT-based long-term pharmacological treatment is associated with a 36% risk reduction of syncope recurrences in patients with syncope of unknown origin.     

Evaluation of outcome of care in patients with haemophilia

Haemophilia is a potentially disabling condition associated with high financial costs, and so the need for robust measures to evaluate outcome of care is essential. This paper is a review of some of the outcome measures commonly used to evaluate treatment in haemophilia and includes quality of life measures, evaluation of the musculoskeletal system and orthopaedic surgical procedures. Quality-of-life questionnaires are discussed with particular reference to the SF36 and AIMS2. Results of published studies to date have demonstrated variable results. Overall, haemophilia appears to reduce quality of life compared to normal population figures. Several factors are perceived to reduce quality of life, and these include being human immunodeficiency virus (HIV) positive, having impairments, and a history of orthopaedic surgery. The evaluation of the musculoskeletal system is important in order to detect any deterioration over time. Various standardized measurement tools are described. Orthopaedic surgical procedures have also been evaluated in patients with haemophilia. To date, the Hospital for Special Surgery Knee rating scale has been the most commonly used to evaluate the outcome of total knee replacement. The limitations of this system for patients with haemophilia are outlined. Overall, these measures provide useful tools for evaluating outcome, but none have been specifically developed for patients with haemophilia. Further studies would be useful to evaluate these tools and others in more depth.     

Etiology of syncope in patients hospitalized with syncope and predictors of mortality and rehospitalization for syncope at 27-month follow-up

The authors investigated the etiologies of syncope and risk factors for mortality and rehospitalization for syncope at 27‐month follow‐up in 325 consecutive patients, mean age 66 years, hospitalized for syncope. The causes of syncope were diagnosed in 241 patients (74%). Of 325 patients, 13 (4%) were rehospitalized for syncope and 38 (12%) died. Stepwise logistic regression analysis showed that significant independent prognostic factors for rehospitalization for syncope were diabetes (odds ratio [OR], 5.7; 95% confidence interval [CI], 1.6–20.4), atrial fibrillation (OR, 4.0; 95% CI, 1.0–15.6), and smoking (OR, 4.6; 95% CI, 1.3–16.8). Stepwise Cox regression analysis showed that significant independent prognostic factors for time to mortality were diabetes (hazard ratio [HR], 2.7; 95% CI, 1.4–5.2), coronary artery bypass graft surgery (HR, 2.9; 95% CI, 1.3–6.5), malignancy history (HR, 2.5; 95% CI, 1.2–5.2), narcotics use (HR, 4.0; 95% CI, 1.7–9.8), smoking (HR, 2.8; 95% CI, 1.4–5.5), atrial fibrillation (HR, 2.4; 95% CI, 1.0–5.4), and volume depletion (HR, 2.8; 95% CI, 1.4–5.8). Copyright © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Long-term outcome of patients with unexplained syncope treated with an electrophysiologic-guided approach in the implantable cardioverter-defibrillator era.

OBJECTIVES: We evaluated the long-term outcome of patients with coronary artery disease and unexplained syncope who were treated with an electrophysiologic (EP)-guided approach. BACKGROUND: Electrophysiologic studies are frequently performed to evaluate unexplained syncope in patients with coronary artery disease. Patients with this profile who have inducible ventricular tachycardia are considered at high risk for sudden death and increased overall mortality, and therefore are often treated with an implantable cardioverter-defibrillator (ICD). The impact of this EP-guided strategy is unknown because there are no data comparing the long-term outcome of ICD recipients with that of noninducible patients. METHODS: We evaluated 67 consecutive patients with coronary artery disease and unexplained syncope. All patients were treated with an EP-guided approach that included ICD implantation in patients with inducible ventricular tachycardia. RESULTS: Electrophysiologic testing suggested a plausible diagnosis in 32 (48%) of these patients. Inducible monomorphic ventricular tachycardia was the most common abnormality. Despite frequent appropriate therapy with ICDs, the total mortality for patients with inducible monomorphic ventricular tachycardia was significantly higher than for noninducible patients. The respective one- and two-year survival rates were 94% and 84% in noninducible patients and 77% and 45% in inducible patients (p = 0.02). CONCLUSIONS: Electrophysiologic testing suggests an etiology for unexplained syncope in approximately 50% of patients and risk stratifies these patients with regard to long-term outcome. Patients who receive an ICD for the management of inducible ventricular tachycardia have a high incidence of spontaneous ventricular arrhythmias requiring ICD therapy. However, despite ICD implantation and frequent appropriate delivery of ICD therapies, patients with inducible ventricular tachycardia have a significantly worse prognosis than do those who are noninducible.