Treatment of Unexplained Syncope: A Multicenter, Randomized Trial of Cardiac Pacing Guided by Adenosine 5'-Triphosphate Testing (original) (raw)
Related papers
Pacing for syncope: what role? which perspective?
European Heart Journal Supplements, 2007
Cardiac pacing is the most effective therapy to prevent syncopal recurrences when syncope is due to bradycardia. Causes of bradycardia-induced syncope are intrinsic [primary dysfunction of the atrioventricular (AV) conduction system and of sinus node function] and extrinsic (vagal reflexes). Intrinsic and extrinsic mechanisms often coexist in the same patient, especially in the case of sick sinus syndrome. Although formal randomized controlled trials have not been performed, cardiac pacing is commonly considered very effective and therefore accepted as therapy of choice in all patients in whom an AV block is responsible for syncope. Cardiac pacing is also commonly indicated in patients in whom syncope is caused by sick sinus syndrome or carotid sinus syndrome. However, owing to the frequently associated vasodepressor reflex, syncope still recurs during long-term observation in 20% of the patients. Despite several controlled trials, the indications for cardiac pacing are still controversial in patients with vasovagal syncope (VVS). To date, cardiac pacing may be only indicated in selected older patients affected by VVS who present with severe recurrent impredictable syncopal attacks affecting quality of life. Also in these patients some rare syncopal recurrence should be expected over the long term.
Syncope in Patients with Pacemakers
Arrhythmia & Electrophysiology Review, 2015
Syncope in a pacemaker patient is a serious symptom but it is rarely due a pacemaker system malfunction. Syncope occurs in about 5 % of patients paced for atrioventricular (AV) block in 5 years, 18% in those paced for sinus node disease in 10 years, 20 % of those paced for carotid sinus syndrome in 5 years and 5–55 % of those older patients paced for vasovagal syncope in 2 years. The vastly different results in vasovagal syncope depend on the results of tilt testing, where those with negative tests approach results in pacing for AV block and those with a positive tilt test show no better results than with no pacemaker. The implication of tilt results is that a hypotensive tendency is clearly demonstrated by tilt positivity pointing to syncope recurrence with hypotension. This problem may be addressed by treatment with vasoconstrictor drugs in those who are suited or, more commonly, a reduction or cessation of hypotensive therapy in hypertensive patients. Other causes of syncope such...
Implications of mechanism of bradycardia on response to pacing in patients with unexplained syncope
Europace, 2007
Asystole >3 s or sinus bradycardia with a ventricular rate <40 in association with complete heart block or sinus node dysfunction are considered to be Class 1 indications for permanent cardiac pacing. Nevertheless, these phenomena may be observed in symptomatic patients with neurocardiogenic syncope, who may not respond to pacing therapy. We hypothesized that the pattern of spontaneous bradycardia in symptomatic patients would distinguish patients with sinus node dysfunction or conduction system disease who would benefit from pacing from patients with neurally-mediated syncope who would derive lesser benefit. Patients with symptomatic spontaneous bradycardia during long-term monitoring for unexplained syncope who underwent pacemaker implantation were classified according to the ISSUE classification system and followed for recurrent syncope. Follow-up included review of medical records, pacemaker clinic visits, and telephone interviews. Loop recorder tracings were reviewed to identify characteristics potentially predicting a favourable response to pacing. Thirty-three patients (21 male; age, 70 +/- 14) were followed for 3.56 +/- 1.71 years. Six patients had a recurrence of syncope during the follow-up. All patients with recurrent syncope despite pacing demonstrated a Type 1A (n = 5) or 1B (n = 1) pattern with gradual onset of bradycardia at baseline, suggesting a neurocardiogenic mechanism. There was no difference in the severity of bradycardia or duration of asystole in baseline loop recorded events in responding and non-responding patients. Multivariate analysis using stepwise logistic regression revealed that the ISSUE classification and the absence of structural heart disease were the only independent predictors of treatment failure of cardiac pacing in patients with spontaneous symptomatic bradycardia. Patients with syncope associated with abrupt bradycardia displayed a better response to cardiac pacing therapy than those with gradual onset bradycardia.
The Etiology of Syncope in Pacemaker Patients
Pacing and Clinical Electrophysiology, 1991
PAVLOVIC, S.U., ET AL.: The Etiology of Syncope in Pacemaker Patients. A total of 46 patients with syncopal episodes after VVI pacemaker implantation were studied. Of these, 92% had one to three syncopal episodes and 8% more than three. All underwent a thorough clinical examination, which included chest X ray, echocardiogram, neurological exam, and the following protocol: 24-hour HoJfer monitoring, EEG, hlood pressure (BP) measurement in three positions, Doppler exam of the carotid vessels, fasting blood glucose, and head-up tilt table test (60 minutes, 60°). Hoiter monitoring showed exit block in two patients (4.3%) and failed sensing in one (2.1%). In two patients there was unilateral slowing on EEG. Orthostatic hypotension was found in four patients (8.6%), and hypoglycemia in three insuJin-dependent diabetics. An occiusive atherosclerotic plaque in the carotid artery was found in three patients {6.5%}. Syncope was induced in 17 patients (36.9%) by the tilt table test, after a mean standing time of 47 ± 11 minutes. The mean resting systolic BP of these patients was 140 ± 24 mmHg, and fell to a mean level of 56 ± 8 mmHg (mean systolic BP drop was 79 ± 8 mmHg). Sixteen of these 17 patients with positive tilt table were being paced at the time of syncope and one had a spontaneous heart rate of 73 beafs/min. In 14 cases (30.4%) the cause of syncopal episodes after this extensive workup remained unexplained. These results indicate that pacemaker dysfunction is a not major cause of syncopal episodes in pacemaker patients and that these are most often due to vasovagal syncope. Long-term follow-up is warranted to determine the prognostic significance of various types of syncope in pacemaker patients. (PACE, Vol. 14, December 1991) pacemaker, artificial syncope, etiology diagnosis of vasovagal syncope.^"^ It is the aim of this study to implement a protocol for the workup of syncope in pacemaker patients in order to determine the prevalence of the various causes of loss of consciousness after pacemaker implantation. Particular attention will be given to the hemodynamic mechanisms of vasovagal syncope in this patient group, using the head-up tilt table test.
Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology, 2015
The aim of this study was to determine the long-term effects and determinants of success of cardiac pacing in patients affected by reflex syncope enrolled in the Syncope Unit Project 2 (SUP 2) study. Initial results have validated the effectiveness of a standardized guideline-based algorithm which can be used in clinical practice in order to select suitable candidates for cardiac pacing. In this prospective, multicentre, observational study, patients aged >40 years, affected by severe unpredictable recurrent reflex syncope, underwent carotid sinus massage (CSM), followed by tilt testing (TT) if CSM was negative, followed by implantation of an implantable loop recorder (ILR) if TT was negative. Those who had an asystolic response to one of these tests received a dual-chamber pacemaker. Of 281 patients who met the inclusion criteria, 137 (49%) received a pacemaker and were followed up for a mean of 26 ± 11 months: syncope recurred in 25 (18%) of them. At 3 years, the actuarial sync...
Pacing and Clinical Electrophysiology, 2013
Background: Few studies have examined the prevalence of permanent pacemaker (PPM) malfunction among patients with a previously implanted pacemaker admitted to the hospital with syncope. Objective: This study sought to examine causes of syncope in patients with a previously implanted pacemaker admitted to our hospital with syncope. Methods: We retrospectively reviewed our hospital admission database for patients who had both keywords "syncope" and "pacemaker" as their diagnoses from January 1, 1995 until June 1, 2012. One hundred and sixty-two patients who were admitted to the hospital because of syncope and had a PPM implanted prior to the index syncopal episode were included. All patients had pacemakers interrogated during the admission. Two independent physicians examined the discharge summary of each patient and determined the cause of syncope in each case. Results: Of the 162 patients studied, eight (4.9%) were found to have pacemaker system malfunction as a cause of syncope. In 96 patients (59.2%), the cause of syncope could not be determined prior to hospital discharge. Among the identifiable causes of syncope, orthostatic hypotension was most prevalent (16%) followed by vasovagal (6%), severe aortic stenosis (4.3%), atrial arrhythmia (3.1%), acute and subacute infection (3.1%), and other less prevalent causes (3.1%). Conclusion: In this study, PPM system malfunction was rarely a cause of syncope in patients admitted to the hospital with a previously implanted device.
Europace, 2013
The aim of this European Heart Rhythm Association (EHRA) survey was to provide an insight into the current practice of work-up and management of patients with syncope among members of the EHRA electrophysiology research network. Responses were received from 43 centres. The majority of respondents (74%) had no specific syncope unit and only 42% used a standardized assessment protocol or algorithm. Hospitalization rates varied from 10% to 25% (56% of the centres) to .50% (21% of the centres). The leading reasons for hospitalization were features suggesting arrhythmogenic syncope (85% of respondents), injury (80%), structural heart disease (73%), significant comorbidities (54%), and older age (41%). Most widely applied tests were electrocardiogram (ECG), echocardiography, and Holter monitoring followed by carotid sinus massage and neurological evaluation. An exercise test, tilt table test, electrophysiological study, and implantation of a loop recorder were performed only if there was a specific indication. The use of a tilt table test varied widely: 44% of respondents almost always performed it when neurally mediated syncope was suspected, whereas 37% did not perform it when there was a strong evidence for neurally mediated syncope. Physical manoeuvres were the most widely (93%) applied standard treatment for this syncope form. The results of this survey suggest that there are significant differences in the management of patients with syncope across Europe, specifically with respect to hospitalization rates and indications for tilt table testing in neurally mediated syncope. The majority of centres reported using ECG, echocardiography, and Holter monitoring as their main diagnostic tools in patients with syncope, whereas a smaller proportion of centres applied specific assessment algorithms. Physical manoeuvres were almost uniformely reported as the standard treatment for neurally mediated syncope.
International journal of cardiology, 2018
Benefit of cardiac pacing in patients with vasovagal syncope (VVS) and cardioinhibitory response to head-up tilt test (HUTT) is still debated. We aimed at retrospectively assessing the long-term effect of cardiac pacing in a cohort routinely followed in our institutions. From a cohort of 1502 patients who performed HUTT between 2008 and 2014, 181 (12%) patients had VASIS 2A (40) or 2B (141) response (median age 43 [interquartile range, 25-56] years, 59% male). Fifty patients (28%) received a dual-chamber pacemaker and 131 (72%) received training on physical maneuvers and medical therapy. The so-called 'Closed Loop Stimulation' (CLS) function was activated for at least 18 months in the pacing group. The 5-year recurrence rate of syncope of paced patients was compared with non-paced patients and with a subgroup of 18 propensity-score matched patients selected among non-paced patients. The 5-year Kaplan-Meier syncope free-rate was 81% (CI, 67%-90%) in the pacing group, 57% (47%...
Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology, 2014
The randomized, double-blind Third International Study on Syncope of Uncertain Etiology (ISSUE-3) showed that dual-chamber permanent pacing was effective in reducing the recurrence of syncope in patients ≥ 40 years with severe asystolic, probably neurally mediated syncope (NMS), documented by implantable loop recorder (ILR). Analysis in ISSUE-3 was performed according to the intention-to-treat principle. In the present study, we performed an on-treatment analysis, which included additionally those non-randomized patients followed up in the ISSUE registry to evaluate in a better manner the effectiveness of cardiac pacing therapy. Initially, 504 patients received an ILR, 162 (32%) patients had a diagnosis consistent with NMS within a mean observation period of 15 ± 11 months: 99 (19%) patients had documentation of syncope with ≥ 3 s asystole or ≥ 6 s asystole without syncope. Sixty patients affected by asystolic NMS received cardiac pacing therapy and 86 (33 asystolic and 53 non-asyst...