A syncope collared / A "nyakon fogott" syncope esete

Carotid sinus syncope is a temporary, exaggerated circulatory response to carotid massage, characterized by marked drop in arterial pressure, and varying degree of bradycardia, or even asystole lasting for several seconds, resulting in short lasting loss of consciousness. A related reflex mediated disorder is a fainting precipitated by a parapharyngeal space-occupying lesion, manifests in prolonged episodes of hemodynamic instability. We report a case, where the hemodynamic features of the syncope are well documented. The case illustrates the potential overlap between pulseless electrical activity and syncope, and a simple noninvasive solution for the frightening symptoms is also suggested.

Complementary effectiveness of carotid sinus massage and tilt testing for the diagnosis of reflex syncope in patients older than 40 years: a cohort study.

AIMS: Indications, methodology, and diagnostic criteria for carotid sinus massage (CSM) and tilt testing (TT) have been standardized by the 2018 Guidelines on Syncope of the European Society of Cardiology. Aim of this study was to assess their effectiveness in a large cohort which reflects the performance under 'real-world' conditions. METHODS AND RESULTS: We analysed all patients who had undergone CSM and TT in the years 2003-2019 for suspected reflex syncope. Carotid sinus massage was performed according to the 'Method of Symptoms'. Tilt testing was performed according to the 'Italian protocol' which consists of a passive phase followed by a sublingual nitroglycerine phase. For both tests, positive test was defined as reproduction of spontaneous symptoms in the presence of bradycardia and/or hypotension. Among 3293 patients (mean age 73 ± 12 years, 48% males), 2019 (61%) had at least one test positive. A bradycardic phenotype was found in 420 patients (13%); of these, 60% were identified by CSM, 37% by TT, and 3% had both test positive. A hypotensive phenotype was found in 1733 patients (53%); of these, 98% were identified by TT and 2% had both TT and CSM positive. CONCLUSION: The overall diagnostic yield of the tests in patients >40-year-old with suspected reflex syncope was 61%. Both CSM and TT are useful for identifying those patients with a bradycardic phenotype, whereas CSM has a limited value for identifying the hypotensive phenotype. Since the overlap of responses between tests is minimal, both CSM and TT should be performed in every patient over 40 years receiving investigation for unexplained but possible reflex syncope.

Trends in Low-Value Carotid Imaging in the Veterans Health Administration From 2007 to 2016.

Importance: As part of the Choosing Wisely campaign, primary care, surgery, and neurology societies have identified carotid imaging ordered for screening, preoperative evaluation, and syncope as frequently low value. Objective: To determine the changes in overall and indication-specific rates of carotid imaging following Choosing Wisely recommendations. Design, Setting, and Participants: This serial cross-sectional study compared annual rates of carotid imaging before Choosing Wisely recommendations (ie, 2007 to 2012) and after (ie, 2013 to 2016) among adults receiving care in the Veterans Health Administration (VHA) national health system. Data analysis was performed from April 10, 2019, to November 27, 2019. Exposures: Release of the Choosing Wisely recommendations. Main Outcomes and Measures: Annual rates of overall imaging, imaging ordered for stroke workup, imaging ordered for low-value indications (ie, screening owing to carotid bruit, preoperative evaluation, and syncope). Indications were identified using a text lexicon algorithm based on electronic health record review of a stratified random sample of 1000 free-text imaging orders. The subsequent performance of carotid procedures within 6 months after carotid imaging was assessed. Results: Between 2007 and 2016, 809 071 carotid imaging examinations were identified (mean [SD] age of patients undergoing imaging, 69 [10] years; 776 632 [96%] men), of which 201 467 images (24.9%) were ordered for low-value indications (67 064 [8.2%] for carotid bruit, 25 032 [3.1%] for preoperative evaluation, and 109 400 [13.5%] for syncope), 257 369 (31.8%) for stroke workup, and 350 235 (43.3%) for other indications. Imaging for carotid bruits declined across the study period while there was no significant change in imaging for syncope or preoperative evaluation. Compared with the 6 years before, during the 4 years following Choosing Wisely recommendations, there was no change in the trend for syncope, a small decline in preoperative imaging (post-Choosing Wisely trend, -0.1 [95% CI, -0.1 to <-0.1] images per 10 000 veterans), and a continued but less steep decline in imaging for carotid bruits (post-Choosing Wisely trend, -0.3 [95% CI, -0.3 to -0.2] images per 10 000 veterans). During the study period, 17 689 carotid procedures were identified, of which 3232 (18.3%) were preceded by carotid imaging ordered for low-value indications. Conclusions and Relevance: These findings suggest that Choosing Wisely recommendations were not associated with a meaningful change in low-value carotid imaging in a national integrated health system. To reduce low-value testing and utilization cascades, interventions targeting ordering clinicians are needed to augment the impact of public awareness campaigns.

Myotonic dystrophy type 1 and high ventricular vulnerability at the electrophysiological evaluation: ICD yes or not?

A significant number of sudden death (SD) is observed in myotonic dystrophy (DM1) despite pacemaker implantation and some consider the ICD to be the preferential device in patients with conduction disease. According to the latest guidelines, prophylactic ICD implantation in patients with neuromuscular disorder should follow the same recommendations of non-ischemic dilated cardiomyopathy, being reasonable when pacing is needed. We here report a case of DM1 patient who underwent ICD implantation even in the absence of conduction disturbances on ECG and ventricular dysfunction/fibrosis at cardiac magnetic resonance. The occurrence of syncope, non-sustained ventricular tachycardias at 24-Holter ECG monitoring and a family history of SD resulted associated with ventricular fibrillation inducibility at electrophysiological study, favouring ICD implantation. On our advice, DM1 patient with this association of SD risk factors should be targeted for ICD implantation.

Risk factors and psychological impact of syncope in migraine patients.

BACKGROUND: Migraine is associated with syncope. We investigated risk factors for syncope and burden of syncope in migraine patients. METHODS: Participants were recruited from a headache clinic. All participants provided information on lifestyle, co-morbidity, syncope, headache and suicide, and completed the MIDAS and HADS questionnaires. Genetic data were available for a subset of participants. Risk of syncope in relation to participant's characteristics and migraine susceptibility loci, and risks of psychological disorders associated with syncope, were calculated using logistic regression. RESULTS: Underweight, regular tea intake, diabetes mellitus, and migraine with aura were associated with increased syncope risks, with adjusted ORs of 1.76 (95% CI 1.03-3.03), 1.84 (95% CI 1.22-2.79), 4.70 (95% CI 1.58-13.95), and 1.78 (95% CI 1.03-3.10), respectively. Preliminary results showed that rs11172113 in LRP1 was associated with syncope risks. Comorbid syncope in migraine patients was associated with increased risks of depression (OR 1.95, 95% CI 1.18-3.22) and suicide attempt (OR 2.85, 95% CI 1.48-5.48). CONCLUSION: Our study showed the potential roles of vascular risk factors in the association between migraine and syncope. Modifiable risk factors for syncope in patients with migraine include body mass index and tea intake. The debilitating psychological impact of co-morbid syncope in migraine patients warrants clinical attention of treating physicians.

Characterization and Management of Arrhythmic Events in Young Patients With Brugada Syndrome.

BACKGROUND: Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited. OBJECTIVES: The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence. METHODS: A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31). RESULTS: Patients' median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents. CONCLUSIONS: Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered.

Flecainide Versus Procainamide in Electrophysiological Study in Patients With Syncope and Wide QRS Duration.

OBJECTIVES: This study sought to compare the differences between procainamide and flecainide to stress the His-Purkinje system during electrophysiological study (EPS) in patients with syncope and bundle branch block (BBB). BACKGROUND: Patients with syncope and BBB are at risk of developing atrioventricular block. EPS is recommended including class I drug challenge to unmask His-Purkinje disease in cases with baseline normal His-ventricular interval. There is little data on differences between different class I drugs. METHODS: This was a prospective study of all consecutive patients undergoing EPS for syncope and BBB at a single center (January 1, 2012 to June 30, 2017). Of those patients with negative baseline EPS, 2 cohorts were compared: group A (historical cohort: procainamide) and group B (flecainide). RESULTS: During the study, 271 patients (age 73.9 ± 12.1 years, 64.9% male, QRS duration: 139.4 ± 13.9 ms) underwent EPS. In 166, baseline EPS was negative and class I drug challenge was performed (90 procainamide, 76 flecainide). The final value and percentage increase in the His-ventricular interval (76 ± 16 ms vs. 64 ± 10 ms and 22.5 ± 6.2% vs. 11.8 ± 5.3%; p < 0.001) and diagnostic yield (14.5% vs. 7.8%, p = 0.04) were higher with flecainide. No differences were found in baseline characteristics. During follow-up (25.8 ± 6.3 months), 39 patients (24.8%) with negative EPS (19.2% with flecainide vs. 30.1% with procainamide: relative risk: 5.1; 95% confidence interval: 2.6 to 10.2; p < 0. 001) received a pacemaker. CONCLUSIONS: Flecainide has a higher diagnostic yield than does procainamide in patients with BBB, syncope, and negative baseline EPS due to a greater increase of the His-ventricular interval. Additionally, there is a lesser need for pacemaker implantation in patients in whom the class I drug test using flecainide was negative.

Syncope, conduction disturbance, and negative electrophysiological test: Predictive factors and risk score to predict pacemaker implantation during follow-up.

BACKGROUND: Patients with syncope and bundle branch block (BBB) are at risk for atrioventricular block (AVB). Electrophysiological study (EPS) can help in identifying patients at higher risk for AVB, but the false-negative rate is remarkable. Few data on the predictors of the need for pacemaker implantation during follow-up have been reported. OBJECTIVE: The purpose of this study was to analyze the rate of patients who need pacemaker implantation after negative EPS and predictive factors. METHODS: A single-center prospective study of 159 consecutive patients (73.9 ± 12.1 years; male 64.9%) with syncope and BBB (January 2012-December 2016) and negative EPS was conducted. An implantable loop recorder was implanted. RESULTS: After 27.9 ± 10.8 months of follow-up, 39 patients (24.8%) underwent pacemaker implantation because of bradyarrhythmia. In the univariate analysis, bifascicular (right BBB + left fascicular block) block, bifascicular block + long PR interval, conduction disturbance different from isolated right BBB, HV ≥60 ms, and HV ≥70 ms after class I drug challenge were predictors of pacemaker implantation. In the multivariate analysis, only bifascicular block (hazard ratio 2.5; 95% confidence interval 1.4-4.8; P = .04) and HV interval ≥60 ms (hazard ratio 3.5; 95% confidence interval 1.8-6.2; P <.001) were statistically significant. A risk score according to the multivariate model identified 3 levels of pacemaker implantation rate (13.5%, 32.7%, and 66.7%; P <.001). No death or severe trauma related to bradyarrhythmia occurred. CONCLUSION: The strategy of an implantable loop recorder in patients with syncope and BBB is safe after negative EPS, but some patients might need pacemaker implantation during follow-up. A risk score based on HV ≥60 ms and bifascicular block can be useful in identifying patients at risk for advanced AVB after negative EPS.

Sudden-onset severe presyncope in a 67-year-old man.

A 67-year-old man presented to the emergency department with sudden onset of severe presyncope. He reported that he had a permanent pacemaker implanted in 2006 following atrioventricular node ablation for persistent atrial fibrillation (AF). After suffering increasing shortness of breath, he underwent upgrade to cardiac resynchronisation therapy (CRT) in 2016. He denied any recent falls, interventions or changes in medication. ECG monitoring showed AF with a broad ventricular escape rhythm at around 25 bpm with pauses of up to 3 s. Placement of a magnet over the device resulted in pacing (figure 1A). The implanted device (Medtronic Syncra C2TR01) was interrogated (figure 1B), and a chest radiograph was obtained (figure 2). heartjnl;105/8/657/F1F1F1Figure 1(A) Twelve-lead ECG demonstrating intrinsic rhythm and pacing after application of magnet. (B) Device interrogation with right ventricular threshold test. heartjnl;105/8/657/F2F2F2Figure 2(C) Anteroposterior chest radiograph demonstrating lead position on admission. QUESTION: What was the cause of this presentation?Noise oversensing on the right ventricular (RV) lead due to lead fracture.The RV septal lead has displaced into the right atrial (RA).RA and RV leads were switched in the can during the CRT upgrade.Increase in threshold of RV and left ventricular (LV) leads resulting in loss of capture.

Dangerous mistake: an accidental caffeine overdose.

Caffeine (1,3,7-trimethylxanthine) is a natural product commonly presented in food's composition, beverages and medicinal products. Generally, it is thought to be safe under normal dosage, yet it can be fatal in case of severe intoxication. We report a case of a healthy 32-year-old woman who went to the local emergency department (ED) 30 min after ingesting, accidentally, 5000 mg of anhydrous caffeine for a preworkout supplement. At the ED, she presented an episode of presyncope followed by agitation. ECG showed polymorphic broad complex QRS tachycardia and arterial blood gas revealed metabolic acidaemia with severe hypokalemia. The dysrhythmia was successfully treated with intravenous propranolol. Acid-base and hydroelectrolytic disorders were also corrected. A persistent sinus tachycardia was observed in the first 2 days in the ward and 5 days later she was discharged asymptomatic with internal medicine follow-up.

Taquicardia ventricular polimórfica durante teste de inclinação na doença de Chagas / Polymorphic ventricular tachycardia during tilt testing in Chagas disease

Paciente do sexo masculino, de 62 anos de idade, com megacólon chagásico sem manifestações cardíacas, apresentou evento sincopal sem pródromos, sendo submetido a Holter de 24 horas, ecocardiografia, teste ergométrico e cineangiocoronariografia, que se mostraram normais. O estudo eletrofisiológico mostrou ausência de distúrbios de condução e de indução de taquiarritmias. Durante a fase basal do teste de inclinação, o paciente apresentou taquicardia ventricular polimórfica. Foi realizado implante de cardioversor-desfibrilador implantável. Na evolução, apresentou deterioração da função ventricular com início de terapêutica específica. Após sete anos de acompanhamento, observaram-se três episódios de taquicardia ventricular polimórfica adequadamente revertidos pelo cardioversor-desfibrilador implantável

A 62 year-old man with Chagasic megacolon without cardiac manifestations developed a syncope without prodrome and was submitted to 24-hour Holter monitoring, echocardiogram, exercise test and coronary angiography. Electrophysiology tests showed there was no conduction and tachyarrhythmia induction disorders. During the baseline phase of the tilt test, the patient presented a polymorphic ventricular tachycardia. An implantable cardioverter defibrillator was implanted. At the follow-up, the patient presented left ventricular deterioration and specific therapy was started. After seven years of follow-up, three episodes of polymorphic ventricular tachycardia were observed and were successfully converted

Feasibility and safety of Reveal LINQ insertion in a sterile procedure room versus electrophysiology laboratory.

BACKGROUND: Insertable cardiac monitors (ICMs) are increasingly utilized for diagnosis of unexplained syncope and arrhythmia monitoring. The Reveal LINQ is a novel miniaturized ICM with improved algorithms. The feasibility and safety of insertion outside the traditional electrophysiology laboratory is unknown. Here we compare outcomes of Reveal LINQ insertion in different environments. METHODS: We report on a prospective, single-centre, non-randomized, observational experience of consecutive Reveal LINQ implantation in the electrophysiology laboratory or a procedure room between October 2013 and October 2015. RESULTS: Of 178 consecutive patients who underwent LINQ device insertion, 80 were implanted in the electrophysiology laboratory and 98 in a procedure room. There were no significant differences in baseline patient characteristics. All implants were performed in the recommended manufacturer method with the exception of 1 which required suture closure. Only a minority received peri-procedural antibiotics with a greater number in the electrophysiology laboratory group (11 [14%] versus 1 [1%], p=0.007). Overall, there were 3 (1.7%) complications with no significant difference between the electrophysiology laboratory and the procedure room groups (2 [3%] versus 1 [1%], p=0.45). There was 1 superficial infection in the procedure room group and 1 superficial infection with device extrusion and 1 traumatic extrusion in the electrophysiology laboratory group. Procedure room implantation subjectively improved laboratory efficiency and patient flow. CONCLUSION: Reveal LINQ insertion can be safely performed outside of the cardiac laboratory provided a sterile technique is followed by the operator using manufacturer recommendations for insertion. These findings have significant resource implications for hospitals undertaking such procedures.

A case report of QT prolongation with glycopyrronium bromide in a patient with chronic tamoxifen use.

BACKGROUND: Glycopyrronium bromide has recently been approved as a once daily maintenance inhalation therapy for moderate to severe chronic obstructive pulmonary disease (COPD). Efficacy and safety trial data have found rare cases of significant QT prolongation. To our knowledge, we describe the first case report of QT prolongation >600 ms with initiation of glycopyrronium bromide in a real world setting. CASE PRESENTATION: A 78-year-old female with moderate COPD recently started on glycopyrronium bromide, presented to Emergency Department (ED) with syncope. Her past medical history was significant for a left total mastectomy and she had been on Tamoxifen for 9 months. One day prior to her presentation, she had visited a naturopathic clinic for a vitamin infusion resulting in emesis. The following day she continued to feel dizzy and had a witnessed syncopal episode without any reported cardiac or neurological symptoms preceding the event or after regaining consciousness. In the emergency department, she reported dizziness and was found to be hypotensive. Her symptoms completely resolved with intravenous fluids. Lab work was normal however her electrocardiogram (ECG) demonstrated a QTc interval of 603 and 631 ms (Friderica and Bazett's respectively) with a normal QT interval on her baseline ECG prior to initiating Tamoxifen. She was admitted to the Cardiology service for further work-up of QT prolongation. Her syncope was felt to be due to orthostatic hypotension and the QT prolongation secondary to medications, which were both discontinued during her admission. After 2 days, her QT interval normalized consistent with the half-life of Glycopyrronium bromide (13-57 h) compared to Tamoxifen (8-14 days). CONCLUSION: Glycopyrronium bromide is guideline recommended as first line therapy for prevention of exacerbation in moderate to severe COPD however safety data had been limited to select populations. This case report highlights the need for future studies to identify high-risk populations at potential risk of life-threatening arrhythmias who may benefit from periodic ECG surveillance.

"Cardio-Neuromodulation" With a Multielectrode Irrigated Catheter: A Potential New Approach for Patients With Cardio-Inhibitory Syncope.

Syncope is frequently neurally mediated and can seriously affect quality of life. Different ablation strategies have been successfully performed. These approaches have not gained wide acceptance and are quite extensive and complex, exposing patients to significant risks. This article reports the case of a 16-year-old girl who was severely affected by frequent and prolonged episodes of syncope and was treated by tailored ablation of the anterior right ganglionated plexus with a multielectrode irrigated catheter. She had fainted >30 times in the 5 years preceding treatment, experiencing approximately 10 severe episodes of syncope in the previous 12 months. After 3 minutes of ablation, the P-P interval was reduced by >400 milliseconds. Syncope disappeared and the patient has remained completely asymptomatic over a follow-up of 22 months. The "reset" basal P-P interval has remained unchanged (follow-up electrocardiogram at 16 months). At 6 months, there was no residual heart rate activity <50 bpm. On 24-hour rhythm registration, P-P intervals ≥1,000 milliseconds (corresponding to a heart rate of ≤60 bpm) were reduced by >16,000 beats. We believe that this case report is original for several reasons: the unusual clinical presentation; the unique structure targeted; the very limited ablation, implying much lower risks for the patient; the anatomical approach; and the different endpoint. This new "cardio-neuromodulation" approach could be useful for the treatment of patients with neurally mediated syncope.

Insight into specific pro-arrhythmic triggers in Brugada and early repolarization syndromes: results of long-term follow-up.

The pro-arrhythmic triggers in Brugada and early repolarization syndromes (BrS, ERS) have not been analyzed systematically except for case reports. We clinically investigated the circumstances which precede/predispose to arrhythmic events in these syndromes during long-term follow-up. A detailed history from the patients/witnesses was taken to investigate the antecedent events in the last few hours that preceded syncope/ventricular fibrillation (VF); medical records, ECG and blood test from the emergency room (ER) were reviewed. 19 patients that fulfilled the investigation criteria were followed up for 71 ± 49 months (34-190 months). Prior to the event (syncope/VF), the patients were partaking different activities in the following decreasing order; drinking alcoholic beverage, having meal, and getting up from sleep, exercise. 3 patients reported mental/physical stress prior to the event and 2 patients developed VF several days after starting oral steroid for treatment of bronchial asthma. In the ER, elevated J-wave amplitude (0.27 ± 0.15 mV) was found with 58 % of the patients having hypokalemia. After electrolyte correction and cessation of steroids, the following day plasma K+ (4.2 ± 0.3 mEq/L, P < 0.001) was significantly increased and J-wave amplitude (0.13 ± 0.1 mV, P < 0.001) was remarkably reduced. Three patients were kept on oral spironolactone/potassium supplements. During follow-up for 71 ± 49 (34-190) months, among 4 patients with VF recurrence, one patient developed VF after taking oral steroid. In ERS and BrS, hypokalemia and corticosteroid therapy add substantial pro-arrhythmic effects, but potentially treatable. Stopping steroid therapy and avoiding hypokalemia had excellent long-term outcome.

Safety and tolerability of Tilt Testing and Carotid Sinus Massage in the octogenarians.

OBJECTIVE: to evaluate the safety and tolerability of Tilt Testing (TT) and Carotid Sinus Massage (CSM) in octogenarians with unexplained syncope. METHODS: patients consecutively referred for transient loss of consciousness to the 'Syncope Units' of three hospitals were enrolled. TT and CSM were performed according to the European Society of Cardiology guidelines on syncope. Complications were evaluated in each group. An early interruption of TT was defined as 'intolerance' and considered as a non-diagnostic response. RESULTS: one thousand four hundred and one patients were enrolled (mean age 72 ± 16 years, male 40.8%). Six hundred and ninety-four patients (49.5%) were 80 years old or older (mean age 83 ± 3 years) and 707 (50.5%) were younger (mean age 60 ± 17 years). Complications after TT occurred in 4.5% of older patients and in 2.1% of the younger ones (P = 0.01). All complications were 'minor/moderate', as prolonged hypotension, observed in ∼3% of patients ≥80 years. Major complications such as sustained ventricular tachycardia, ventricular fibrillation, asystole requiring cardiac massage, transient ischaemic attack, stroke and death were not observed in any patient. The presence of orthostatic hypotension and the mean number of syncopal episodes were predictors of TT complications. Intolerance was reported in 2.4% of older patients and 1% of the younger ones (P = 0.08), mainly due to orthostatic intolerance. No complications occurred after CSM. CONCLUSIONS: TT and CSM appear to be safe and well tolerated in octogenarians, who should not be excluded by age from the diagnostic work-up of syncope.

Electrophysiological study generally is negative in patients <40 years suspected of supraventricular tachycardia but also complaining of chest pain and/or syncope.

BACKGROUND: The diagnosis of paroxysmal supraventricular tachycardia (SVT) frequently is a dilemma. Electrophysiological study (EPS) is the only means to evaluate the nature of symptoms when noninvasive studies remain negative. Our objectives were to determine the clinical factors of negativity or positivity of (EPS) in patients suspected of SVT. METHODS: EPS was performed in 2650 patients complaining of tachycardia and suspected of SVT. Transesophageal EPS consisted of programmed atrial stimulation in control state and after isoproterenol. Patients were followed from 1 month to 18 years (2.93 ± 4 years). RESULTS: SVT was induced in 1944 patients, age 48 ± 19.5. EPS remained negative in 706 patients, age 34 ± 17 (p<0.0001). Age <40 years, feeling of dizziness/syncope or chest pain associated with tachycardia, the absence of heart disease or short PR interval was more frequent in patients with negative EPS (respectively 64, 42, 26, 96, 88.5%) than in patients with induced SVT (34, 14, 4, 88, 59%) (p<0.0001).The positive predictive value for the prediction of a negative EPS of age <40, chest pain, syncope or their association was 63.5, 42, 26.5, 11% and negative predictive value was 66, 86, 94.5, 99.5%. At multivariate analysis, age <40 (0.000, OR 2.79), the presence of syncope associated with tachycardia (0.000, OR 5.075) or chest pain (0.000, OR 17.923) was an independent factor of negative EPS. CONCLUSIONS: Among patients complaining of nondocumented tachycardia, suspected of SVT, the association of tachycardia with chest pain and/or syncope and age <40 years generally was correlated with a negative EPS and did not indicate initially invasive studies. In the remaining patients transesophageal EPS is indicated.