Impact of dual-chamber pacing with closed loop stimulation on quality of life in patients with recurrent reflex vasovagal syncope: results of the SPAIN study.

AIMS: Reflex vasovagal syncope (VVS) is the most common cause of syncope and patients with recurrent episodes may severely impair quality of life (QoL). This pre-specified analysis evaluated whether the clinically significant reduction in syncope burden demonstrated by dual-chamber pacing with closed loop stimulation (DDD-CLS) reported in the SPAIN trial translates into improved QoL. METHODS AND RESULTS: Patients aged ≥40 years with ≥5 VVS episodes and cardioinhibitory response induced by head-up tilt testing were included. Patients were randomized 1:1 to active DDD-CLS pacing algorithm for 12 months followed by sham DDI mode for the remaining 12 months (Group A) or vice versa (Group B). QoL was assessed using the Short Form-36 (SF-36) health survey, Physical Component Score (PCS), and Mental Component Score (MCS) before randomization (baseline) and at 12- and 24-month follow-up. Fifty-four patients were enrolled from 11 participating centres. No significant carryover effect was detected for any variable, and the only period effect was observed in the vitality subdomain (P = 0.033). Mean SF-36 scores were higher in the DDD-CLS group vs. the DDI group for the eight subdomains and significantly different in physical role, bodily pain, and vitality (P < 0.05). The analysis of component summary scores indicated that DDD-CLS benefited both mental and physical components with significant differences in PCS when compared with the DDI group. CONCLUSION: Dual-chamber pacing with closed loop stimulation determined a significant and clinically relevant improvement in QoL across both mental and physical components in patients with recurrent VVS. REGISTRATION: Closed Loop Stimulation for Neuromediated Syncope (SPAIN Study); NCT01621464.

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

BACKGROUND: Pacing in vasovagal syncope remains controversial. OBJECTIVES: The authors evaluated dual-chamber pacing with closed loop stimulation (DDD-CLS) in patients with cardioinhibitory vasovagal syncope. METHODS: This 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. RESULTS: A 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). CONCLUSIONS: DDD-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).

Prognostic value of the electrocardiogram in patients with syncope: data from the group for syncope study in the emergency room (GESINUR).

BACKGROUND: The Group for Syncope Study in the Emergency Room (GESINUR) was a Spanish multicenter, prospective, observational study that evaluated the clinical presentation and acute management of loss of consciousness in Spain. Several studies have shown that an abnormal ECG is a poor prognostic factor in patients with syncope. However, the prognostic significance of each ECG abnormality is not well known. OBJECTIVE: The purpose of this study was to study the association between specific ECG abnormalities and mortality in patients with syncope from the GESINUR study. METHODS: All patients in the GESINUR study who had syncope and had available, readable ECG and 12-month follow-up data were included in this retrospective observational study (n = 524, age 57 ± 22 years, 50.6% male). ECG abnormalities were analyzed and assessed to evaluate whether an association with all-cause mortality existed at 12 months. RESULTS: ECGs were classified as abnormal in 344 patients (65.6%). Thirty-three patients died during follow-up (6.3%), but only 1 due to sudden cardiovascular death. Atrial fibrillation (odds ratio [OR] 6.8, 95% confidence interval [CI] 2.8-16.3, P <.001), intraventricular conduction disturbances (OR 3.8, 95% CI 1.7-8.3, P = .001), left ventricular hypertrophy ECG criteria (OR 6.3, 95% CI 1.5-26.3, P = .011), and ventricular pacing (OR 21.8, 95% CI 4.1-115.3, P <.001) were the only independent ECG predictors of all-cause mortality. CONCLUSION: Although an abnormal ECG in patients with syncope is a common finding, only the presence of atrial fibrillation, intraventricular conduction disturbances, left ventricular hypertrophy ECG criteria, and ventricular pacing is associated with 1-year all-cause mortality.

Medium-term results of cryoballoon ablation of the pulmonary veins in patients with paroxysmal and persistent atrial fibrillation. First experience of a Spanish center.

PURPOSE: Cryoballoon ablation of the pulmonary veins (CAPV) is a new technique that could have similar results to radiofrequency procedures, but with fewer complications. We analyzed the outcomes and safety of this technique in a consecutive cohort of patients with atrial fibrillation (AF). METHODS: A total of 63 patients with paroxysmal (n = 40) or persistent (n = 23) AF were studied. Patient follow-up was performed at 3 months and then every 6 months with 72-h continuous electrocardiographic recordings. RESULTS: A total of 262 pulmonary veins were treated; 60.3 % of the cases presented normal pulmonary vein drainage with 4 pulmonary veins, and 23.8 % of the cases presented a common left-sided antrum. Complete isolation of all veins was achieved in 95.2 % of cases with 10.3 ± 2.8 (mean ± standard deviation) applications per patient. Transient right phrenic nerve injury was the most common complication (4.7 %). Median follow-up was 5.5 months. The probability of being free of recurrence at 1 and 2 years was, respectively, 86.2 and 72.2 % for paroxysmal AF and 49 and 36.4 % for persistent AF (P = 0.012). Patients with structural heart disease experienced recurrence more often than patients with a normal heart (62.5 versus 24.5 %; P = 0.03). CONCLUSIONS: CAPV appears to be a safe and effective procedure for the treatment of patients with AF, particularly those with paroxysmal AF and no structural heart disease.

Outcome of patients with syncope beyond the implantable loop recorder.

AIMS: The implantation of an implantable loop recorder (ILR) leads to the diagnosis in about 35% of patients with syncope of unknown origin. Information on outcome of patients in whom a diagnosis is not reached during the lifetime of the device is scarce. The aim of our study is to determine the outcome of these patients in terms of syncope recurrence and survival. METHODS AND RESULTS: An ILR was implanted to 97 patients with syncope of unknown origin. Patients were classified in groups A and B depending on their high or low risk, respectively, of having arrhythmic syncope. Diagnosis had not been reached in 60 patients (62%) when the ILR battery reached end operational life. Five patients were lost to follow up. During a median follow-up of 48 months after ILR explantation (interquartile range 36-56), 22 patients (40%) had recurrence of syncope (32% in group A vs. 48% in group B, P = 0.3). Syncopes with no neurally mediated profile were more frequent in group A (18 vs. 0%, P = 0.05) and neurally mediated profile syncopes were more frequent in group B (44 vs. 11%, P = 0.007). Five patients died, four of them in group A and 1 in group B (P = 0.4). No sudden or cardiac deaths were detected during follow-up. All deaths were due to non-cardiac causes. CONCLUSION: Recurrent syncope is common in patients in whom a diagnosis is not established after the full battery life of an ILR. The prognosis of these patients seems to be good, without observed sudden or cardiac death.

Ablation or conservative management of electrical storm due to monomorphic ventricular tachycardia: differences in outcome.

AIMS: Electrical storm (ES) is a life-threatening condition that predicts bad prognosis. Treatment includes antiarrhythmic drugs (AAD) and catheter ablation (CA). The present study aims to retrospectively compare prognosis in terms of survival and ES recurrence in 52 consecutive patients experiencing a first ES episode. METHODS AND RESULTS: Patients were admitted from 1995 to 2011 and treated for ES by conservative therapy (pharmacological, 29 patients) or by CA (23 patients), according to the physician's preference and time of occurrence, i.e. conservative treatments were more frequently administered during the first years of the study, as catheter ablation became more frequent as the years passed by. After a median follow-up of 28 months, no differences either in survival (32% vs. 29% P = 0.8) or in ES recurrence (38% in ablated vs. 57% in non-ablated patients, P = 0.29) were observed between groups. Low left ventricle ejection fraction (LVEF) was the only variable associated with ES recurrence in ablated patients. When including patients with LVEF > 25%, ES recurrence was significantly lower in ablated patients (24 months estimated risk of ES recurrence was 21% vs. 62% in ablated and non-ablated patients, respectively); however, no benefit in survival was observed. CONCLUSION: Our data suggest that in most patients, especially those with an LVEF > 25%, catheter ablation following a first ES episode, decreases the risk of ES recurrence, without increasing survival.

Diagnosis, management, and outcomes of patients with syncope and bundle branch block.

AIMS: Although patients with syncope and bundle branch block (BBB) are at high risk of developing atrio-ventricular block, syncope may be due to other aetiologies. We performed a prospective, observational study of the clinical outcomes of patients with syncope and BBB following a systematic diagnostic approach. METHODS AND RESULTS: Patients with ≥1 syncope in the last 6 months, with QRS duration ≥120 ms, were prospectively studied following a three-phase diagnostic strategy: Phase I, initial evaluation; Phase II, electrophysiological study (EPS); and Phase III, insertion of an implantable loop recorder (ILR). Overall, 323 patients (left ventricular ejection fraction 56 ± 12%) were studied. The aetiological diagnosis was established in 267 (82.7%) patients (102 at initial evaluation, 113 upon EPS, and 52 upon ILR) with the following aetiologies: bradyarrhythmia (202), carotid sinus syndrome (20), ventricular tachycardia (18), neurally mediated (9), orthostatic hypotension (4), drug-induced (3), secondary to cardiopulmonary disease (2), supraventricular tachycardia (1), bradycardia-tachycardia (1), and non-arrhythmic (7). A pacemaker was implanted in 220 (68.1%), an implantable cardioverter defibrillator in 19 (5.8%), and radiofrequency catheter ablation was performed in 3 patients. Twenty patients (6%) had died at an average follow-up of 19.2 ± 8.2 months. CONCLUSION: In patients with syncope, BBB, and mean left ventricular ejection fraction of 56 ± 12%, a systematic diagnostic approach achieves a high rate of aetiological diagnosis and allows to select specific treatment.

Síncope y bloqueo de rama. Rendimiento del uso escalonado del estudio electrofisiológico y de la monitorización electrocardiográfica prolongada / Syncope and bundle branch block. Diagnostic yield of a stepped use of electrophysiology study and implantable loop recorders

Introducción y objetivos. El objetivo del estudio es evaluar la utilidad de un protocolo diagnóstico escalonado mediante estudio electrofisiológico (EEF) y registrador de eventos implantable (REI) en pacientes con síncope y bloqueo de rama (BR). Métodos. Se realizó un EEF con provocación farmacológica con procainamida en 85 pacientes consecutivos remitidos por síncope y BR tras una evaluación inicial no diagnóstica. En aquellos sin indicación de desfibrilador implantable, se implantó un REI. Se realizó seguimiento hasta el diagnóstico o el agotamiento de la batería del dispositivo. Resultados. El EEF fue diagnóstico en 36 pacientes (42%); el mecanismo más frecuente fue el bloqueo auriculoventricular (BAV) paroxístico (n=27), seguido por la taquicardia ventricular (TV) (n=6). Todos los pacientes con TV tuvieron cardiopatía estructural y mayor prevalencia de BR izquierda. Se implantó un REI a 38 pacientes, y se alcanzó un diagnóstico en 13 (34%); el BAV paroxístico fue el más frecuente (n=10). La mediana de seguimiento hasta el diagnóstico de BAV paroxístico mediante el REI fue 97 días (intervalo intercuartilo, 60-117 días). El BAV paroxístico fue más frecuente en los pacientes con BR derecha y PR prolongado y/o desviación del eje. No se observaron TV o muertes arrítmicas durante el seguimiento. Conclusiones. En pacientes con síncope y BR, la etiología principal está representada por el BAV paroxístico, seguido por la TV. El uso escalonado del EEF y del REI en los casos negativos permite alcanzar un rendimiento diagnóstico alto y con seguridad, dado que la TV suele identificarse durante el EEF(AU)

Introduction and objectives: The objective of this study was to determine the diagnostic yield of a stepped protocol involving an electrophysiologic study (EPS) and implantable loop recorders (ILR) in patients with syncope and bundle branch block (BBB). Methods: Eighty-five consecutive patients referred for syncope and BBB after initial non-diagnostic assessment underwent EPS including a pharmacological challenge with procainamide. Those patients without indication for defibrillator implantation received ILRs. Follow-up continued until diagnosis or end of battery life. Results: The EPS was diagnostic in 36 patients (42%). The most frequent diagnoses were paroxysmal atrioventricular block (AVB) (n = 27), followed by ventricular tachycardia (VT) (n = 6). All patients with VT had structural heart disease; left BBB was more prevalent in this group. Thirty-eight patients received ILRs and diagnosis was achieved in 13 (34%) of them; paroxysmal AVB (n = 10) was the most frequent diagnosis. Median follow-up to diagnosis of paroxysmal AVB was 97 days (interquartile range 60-117 days). Paroxysmal AVB was more frequent in patients with right BBB and prolonged PR interval and/or axis deviation. We found no occurrence of VT or arrhythmic death during follow-up. Conclusions: The most common etiology of syncope in patients with BBB was paroxysmal AVB, followed by VT. The stepped use of EPS and ILR in negative patients enables us to safely achieve a high diagnostic yield, given that VT is usually diagnosed during EPS(AU)

Syncope and bundle branch block. Diagnostic yield of a stepped use of electrophysiology study and implantable loop recorders.

INTRODUCTION AND OBJECTIVES: The objective of this study was to determine the diagnostic yield of a stepped protocol involving an electrophysiologic study (EPS) and implantable loop recorders (ILR) in patients with syncope and bundle branch block (BBB). METHODS: Eighty-five consecutive patients referred for syncope and BBB after initial non-diagnostic assessment underwent EPS including a pharmacological challenge with procainamide. Those patients without indication for defibrillator implantation received ILRs. Follow-up continued until diagnosis or end of battery life. RESULTS: The EPS was diagnostic in 36 patients (42%). The most frequent diagnoses were paroxysmal atrioventricular block (AVB) (n=27), followed by ventricular tachycardia (VT) (n=6). All patients with VT had structural heart disease; left BBB was more prevalent in this group. Thirty-eight patients received ILRs and diagnosis was achieved in 13 (34%) of them; paroxysmal AVB (n=10) was the most frequent diagnosis. Median follow-up to diagnosis of paroxysmal AVB was 97 days (interquartile range 60-117 days). Paroxysmal AVB was more frequent in patients with right BBB and prolonged PR interval and/or axis deviation. We found no occurrence of VT or arrhythmic death during follow-up. CONCLUSIONS: The most common etiology of syncope in patients with BBB was paroxysmal AVB, followed by VT. The stepped use of EPS and ILR in negative patients enables us to safely achieve a high diagnostic yield, given that VT is usually diagnosed during EPS.

Epidemiological characteristics and diagnostic approach in patients admitted to the emergency room for transient loss of consciousness: Group for Syncope Study in the Emergency Room (GESINUR) study.

AIMS: To assess the clinical presentation and acute management of patients with transient loss of consciousness (T-LOC) in the emergency department (ED). METHODS AND RESULTS: A multi-centre prospective observational study was carried out in 19 Spanish hospitals over 1 month. The patients included were > or =14 years old and were admitted to the ED because of an episode of T-LOC. Questionnaires and corresponding electrocardiograms (ECGs) were reviewed by a Steering Committee (SC) to unify diagnostic criteria, evaluate adherence to guidelines, and diagnose correctly the ECGs. We included 1419 patients (prevalence, 1.14%). ECG was performed in 1335 patients (94%) in the ED: 498 (37.3%) ECGs were classified as abnormal. The positive diagnostic yield ranged from 0% for the chest X-ray to 12% for the orthostatic test. In the ED, 1217 (86%) patients received a final diagnosis of syncope, whereas the remaining 202 (14%) were diagnosed of non-syncopal transient loss of consciousness (NST-LOC). After final review by the SC, 1080 patients (76%) were diagnosed of syncope, whereas 339 (24%) were diagnosed of NST-LOC (P < 0.001). Syncope was diagnosed correctly in 84% of patients. Only 25% of patients with T-LOC were admitted to hospitals. CONCLUSION: Adherence to clinical guidelines for syncope management was low; many diagnostic tests were performed with low diagnostic yield. Important differences were observed between syncope diagnoses at the ED and by SC decision.

La ablación transcatéter: una técnica de la cardiología práctica diaria / Transcatheter ablation. A routine cardiology technique

La ablación transcatéter, especialmente con energía de radiofrecuencia, ha sido el avance más significativo de la arritmología y uno de los de mayor impacto global en la cardiología de los últimos 25 años. Su introducción clínica en 1982 para la interrupción de la conducción auriculoventricular se siguió, a principios de los noventa, de la demostración amplia de su eficacia en el tratamiento curativo de pacientes con vías accesorias y en pacientes con taquicardias por reentrada nodal. Posteriormente se añadieron el aleteo auricular, las taquicardias auriculares y las taquicardias ventriculares idiopáticas. El abordaje de las taquicardias ventriculares asociadas a cardiopatía estructural permite en muchos casos el control total de la arritmia, mientras que en cualquier caso puede utilizarse como parte de una terapia híbrida, junto con los fármacos y los dispositivos implantables. Por último, las técnicas de ablación de la fibrilación auricular, en pleno desarrollo, han venido a completar una oferta terapéutica que el cardiólogo clínico puede y debe ofrecer a los pacientes con arritmias (AU)

Transcatheter ablation, especially with radiofrequency energy, is the most significant advance in arrhythmology and is one of the developments that has had the greatest impact on the whole field of cardiology over the last 25 years. It was introduced into clinical practice in 1982 to block atrioventricular conduction. This was followed at the beginning of the 1990s by widespread evidence that the technique was effective as curative treatment for patients with accessory pathways or atrioventricular nodal reentrant tachycardia. Subsequently, atrial flutter, atrial tachycardia and idiopathic ventricular tachycardia were added to the list. Using the technique to treat ventricular tachycardias associated with structural heart disease enables these arrhythmias to be completely controlled in many cases. In addition, the technique can also be used as part of hybrid therapy together with drugs and implantable devices. Finally, techniques for ablating atrial fibrillation, which are currently under development, complete the range of treatment choices that clinical cardiologists can and should offer to patients with arrhythmias (AU)

Reproducibility of electrocardiographic findings in patients with suspected reflex neurally-mediated syncope.

The reproducibility of electrocardiographic (ECG) recordings in syncopal recurrences and the diagnostic role of nonsyncopal arrhythmias are not well known. The objective of this study was to analyse the reproducibility of the ECG findings recorded with implantable loop recorders in 41 patients with suspected neurally-mediated syncope who were included in the International Study on Syncope of Uncertain Origin-2 study and that had > or =2 events recorded by implantable loop recorders. In these patients, the electrocardiogram obtained with the first documented syncope (index syncope) was compared with other recorded events. Twenty-two patients had > or =2 syncopes, and their electrocardiograms were reproducible in 21 (95%): 15 with sinus rhythm, 5 with asystole, and 1 with ventricular tachycardia; 1 had asystole at first syncope and sinus rhythm at recurrent syncope. In 32 patients with nonsyncopal episodes, an arrhythmia was documented in 9, and all of them had the same arrhythmia during the index syncope (100% reproducibility); conversely, when sinus rhythm was documented (23 patients) during nonsyncopal episodes, an arrhythmia was still documented in 6 during the index syncope (70% reproducibility; p = 0.0004). In conclusion, the ECG findings during the first syncope are highly reproducible in subsequent syncopes. The presence of an arrhythmia during nonsyncopal episodes is also highly predictive of the mechanism of syncope, but the presence of sinus rhythm does not rule out the possibility of arrhythmia during syncope. Therefore the finding of an arrhythmia during a nonsyncopal episode allows the etiologic diagnosis of syncope, and eventually to anticipate treatment, without waiting for syncope.

Implantation of single-lead atrioventricular permanent pacemakers guided by electroanatomic navigation without the use of fluoroscopy.

AIMS: Fluoroscopy is the standard and almost unique tool used for cardiac imaging during permanent pacemaker implantation, and its use implies exposure of patients and operators to radiation. The usefulness for this purpose of electroanatomic systems not based on fluoroscopy is unknown. Our aim was to study the feasibility of implanting single-lead VDD pacemakers without the use of fluoroscopy. METHODS AND RESULTS: EnSite NavX, a catheter navigation tool based on the creation of a voltage gradient across the thorax of the patient, was used as an exclusive imaging tool during the implantation of single-lead atrioventricular (VDD) permanent pacemakers in 15 consecutive patients with atrioventricular block and normal sinus node function. A retrospective series of 15 consecutive patients in whom VDD pacemakers were implanted under fluoroscopic guidance was used as a control group. The pacemaker could be implanted in all patients. Time spent to obtain the right ventricle anatomy was 10.1 +/- 5.4 min and time to place the lead in an adequate position was 10.1 +/- 7.8 min. Total implant time was 59.3 +/- 15.6 min (51.5 +/- 12.3 min in the control group; P = 0.14). In one patient, a short pulse of radioscopy was needed for a correct catheterization of the subclavian vein. No complications were observed during the procedure. One lead dislodgement that required re-operation was detected 24 h after implantation. At 3 months follow-up, all pacemakers were functioning properly, with adequate pacing and sensing thresholds. CONCLUSION: Electroanatomic navigation systems such as NavX can be used for cardiac imaging during single-lead atrioventricular pacemaker implantation as a reliable and safe alternative to fluoroscopy.

Syncopal monomorphic ventricular tachycardia with pleomorphism, sensitive to antitachycardia pacing in a patient with Brugada syndrome.

Polymorphic ventricular tachycardia and ventricular fibrillation are the most common arrhythmias in Brugada syndrome, causing syncope or sudden death. Sustained monomorphic ventricular tachycardias are rare in this context. We report the case of a 41-year-old man with repetitive syncopal episodes and an ajmaline-induced characteristic Brugada ECG pattern, in whom episodes of monomorphic ventricular tachycardia with pleomorphism and response to ventricular pacing were documented.

[Therapeutic success of a prospective cardioversion protocol for persistent atrial fibrillation]. / Rendimiento terapéutico de un protocolo prospectivo de cardioversión en la fibrilación auricular persistente.

INTRODUCTION AND OBJECTIVES: The best therapeutic approach for persistent atrial fibrillation has yet to be defined. Our aim was to investigate the effects of cardioversion in unselected patients with persistent atrial fibrillation who were treated according to a strict protocol involving pretreatment, cardioversion, and follow-up. METHODS: Consecutive patients with persistent atrial fibrillation of at least 1 months' duration were included prospectively in a cardioversion protocol that involved standard antiarrhythmic pretreatment, with amiodarone being offered first, and follow-up. RESULTS: The study included 295 patients, 87.5% of whom were taking the antiarrhythmic drug amiodarone. Sinus rhythm was restored in 92.5%, with pharmacologic cardioversion occurring in 9.5%. The recurrence rate was 33.5% in the first month and 54.9% by month 12. Antiarrhythmic treatment had to be modified in 10.8% of patients. Independent risk factors for recurrence during the first year after cardioversion were an atrial fibrillation duration greater than one year, previous cardioversion, and left ventricular dilatation. A simple risk scoring system was able to differentiate between subgroups of patients with a low, intermediate or high risk of recurrence in the first year after cardioversion. CONCLUSIONS: Sinus rhythm was maintained for 1 year after effective cardioversion in 45.1% of patients who received homogeneous antiarrhythmic pretreatment. There were few side effects. Recurrence can be predicted using clinical variables such as left ventricular dilatation, arrhythmia duration, and previous cardioversion.

Effectiveness of physical counterpressure maneuvers in preventing vasovagal syncope: the Physical Counterpressure Manoeuvres Trial (PC-Trial).

OBJECTIVES: In this study, we assessed the effectiveness of physical counterpressure maneuvers (PCM) in daily life. BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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).

Rendimiento terapéutico de un protocolo prospectivo de cardioversión en la fibrilación auricular persistente / Therapeutic success of a prospective cardioversion protocol for persistent atrial fibrillation

Introducción y objetivos. La mejor estrategia de tratamiento de la fibrilación auricular persistente está por definir. Hemos querido conocer los resultados de la cardioversión en pacientes no seleccionados en los que se aplica un protocolo estricto de preparación, cardioversión y seguimiento. Métodos. Incluimos prospectivamente a pacientes consecutivos con fibrilación auricular persistente de al menos un mes de duración en un protocolo de cardioversión eléctrica con pretratamiento antiarrítmico estandarizado (amiodarona como primera opción) y seguimiento. Resultados. Se incluyó a 295 pacientes, el 87,5% de los cuales tomó amiodarona como fármaco antiarrítmico. Se consiguió restaurar el ritmo sinusal en el 92,5%; en un 9,5% de los casos la cardioversión fue farmacológica. Las recurrencias fueron del 33,5 y el 54,9% a uno y 12 meses. El tratamiento antiarrítmico se tuvo que modificar en un 10,8% de los pacientes. Los predictores independientes de recurrencia durante el primer año fueron la duración de la fibrilación auricular mayor de un año, las cardioversiones previas y la dilatación del ventrículo izquierdo. Una sencilla puntuación de riesgo permite diferenciar a los subgrupos de pacientes con bajo, intermedio y alto riesgo de recurrencia durante el primer año tras la cardioversión. Conclusiones. El mantenimiento del ritmo sinusal tras una cardioversión efectiva en pacientes con un pretratamiento antiarrítmico homogéneo es del 45,1% al año de seguimiento. Los efectos secundarios son escasos. La recurrencia puede predecirse con el uso de variables clínicas, como la dilatación ventricular izquierda, la duración de la arritmia y la historia de cardioversiones previas

Introduction and objectives. The best therapeutic approach for persistent atrial fibrillation has yet to be defined. Our aim was to investigate the effects of cardioversion in unselected patients with persistent atrial fibrillation who were treated according to a strict protocol involving pretreatment, cardioversion, and follow-up. Methods. Consecutive patients with persistent atrial fibrillation of at least 1 months' duration were included prospectively in a cardioversion protocol that involved standard antiarrhythmic pretreatment, with amiodarone being offered first, and follow-up. Results. The study included 295 patients, 87.5% of whom were taking the antiarrhythmic drug amiodarone. Sinus rhythm was restored in 92.5%, with pharmacologic cardioversion occurring in 9.5%. The recurrence rate was 33.5% in the first month and 54.9% by month 12. Antiarrhythmic treatment had to be modified in 10.8% of patients. Independent risk factors for recurrence during the first year after cardioversion were an atrial fibrillation duration greater than one year, previous cardioversion, and left ventricular dilatation. A simple risk scoring system was able to differentiate between subgroups of patients with a low, intermediate or high risk of recurrence in the first year after cardioversion. Conclusions. Sinus rhythm was maintained for 1 year after effective cardioversion in 45.1% of patients who received homogeneous antiarrhythmic pretreatment. There were few side effects. Recurrence can be predicted using clinical variables such as left ventricular dilatation, arrhythmia duration, and previous cardioversion

Lack of correlation between the responses to tilt testing and adenosine triphosphate test and the mechanism of spontaneous neurally mediated syncope.

AIMS: We prospectively correlated the results of tilt testing (TT) and adenosine triphosphate test (ATP) with the findings observed during a spontaneous syncopal relapse by means of an implantable loop recorder (ILR) in patients with a clinical diagnosis of neurally mediated syncope. METHODS AND RESULTS: We included patients with three or more clinically severe syncopal episodes in the last 2 years without significant electrocardiographic and cardiac abnormalities. Patients with orthostatic hypotension and carotid sinus syncope were excluded. After ILR implantation, patients were followed until the first documented syncope. Among 392 enrolled patients, 343 underwent TT, which was positive in 164 (48%), and 180 ATP test, which was positive in 53 (29%). Syncope was documented by ILR in 106 (26%) patients after a median of 3 months. Patients with positive and negative TT had similar baseline characteristics, syncopal recurrence rate, and mechanism of syncope, but those with positive TT had more frequently no or slight rhythm variations during spontaneous syncope (45 vs. 21%, P=0.02). An asystolic pause was more frequently found during spontaneous syncope than during TT (45 vs. 21%, P=0.02), but there was a trend for those with an asystolic response during TT also to have an asystolic response during spontaneous syncope (75 vs. 37%, P=0.1). Patients with positive ATP test responses showed syncopal recurrence rates and mechanism of syncope similar to those with negative ATP tests. CONCLUSION: In patients with neurally mediated syncope, clinical characteristics, outcome, and mechanism of syncope are poorly correlated and not predicted by the results of TT and ATP test. Therefore, these tests are of little or no value in guiding specific therapy.

Early application of an implantable loop recorder allows effective specific therapy in patients with recurrent suspected neurally mediated syncope.

AIMS: This prospective multicentre observational study assessed the efficacy of specific therapy based on implantable loop recorder (ILR) diagnostic observations in patients with recurrent suspected neurally mediated syncope (NMS). METHODS AND RESULTS: Patients with three or more clinically severe syncopal episodes in the last 2 years without significant electrocardiographic and cardiac abnormalities were included. Orthostatic hypotension and carotid sinus syncope were excluded. After ILR implantation, patients were followed until the first documented syncope (Phase I). The ILR documentation of this episode determined the subsequent therapy and commenced Phase II follow-up. Among 392 patients, the 1-year recurrence rate of syncope during Phase I was 33%. One hundred and three patients had a documented episode and entered Phase II: 53 patients received specific therapy [47 a pacemaker because of asystole of a median 11.5 s duration and six anti-tachyarrhythmia therapy (catheter ablation: four, implantable defibrillator: one, anti-arrhythmic drug: one)] and the remaining 50 patients did not receive specific therapy. The 1-year recurrence rate in 53 patients assigned to a specific therapy was 10% (burden 0.07 +/- 0.2 episodes per patient/year) compared with 41% (burden 0.83 +/- 1.57 episodes per patient/year) in the patients without specific therapy (80% relative risk reduction for patients, P = 0.002, and 92% for burden, P = 0.002). The 1-year recurrence rate in patients with pacemakers was 5% (burden 0.05 +/- 0.15 episodes per patient/year). Severe trauma secondary to syncope relapse occurred in 2% and mild trauma in 4% of the patients. CONCLUSION: A strategy based on early diagnostic ILR application, with therapy delayed until documentation of syncope allows a safe, specific, and effective therapy in patients with NMS.

Significance of tilt table testing in patients with suspected arrhythmic syncope and negative electrophysiologic study.

BACKGROUND: The diagnostic significance of a tilt table test (TTT) in patients with a suspected arrhythmic etiology for syncope and negative electrophysiologic study (EPS) has not been previously assessed comparing the TTT results with the findings of prolonged monitoring using an implantable loop recorder (ILR). We sought to assess the diagnostic yielding of TTT in patients with suspected arrhythmic syncope and negative EPS. METHODS AND RESULTS: In 81 patients with suspected arrhythmic etiology for syncope and negative EPS, TTT was performed and an ILR implanted regardless the results of TTT. TTT was positive in 38 patients. During follow-up, syncope or presyncope recurred in 32 patients (39.5%). No differences were found in recurrence rates in patients with positive and negative TTT (31.5% vs 46.5%, P = ns). According to rhythm registered during ILR activation, mechanisms of syncopal events were classified as: arrhythmic (atrioventricular [AV] block and ventricular tachycardia; n = 18), neurally mediated (sinus bradycardia and sinus pause; n = 9), and indeterminate (normal sinus rhythm; n = 5). There was no statistical association between the results of TTT and the mechanism of syncope. CONCLUSIONS: In patients with a suspected arrhythmic etiology for syncope and a negative EPS, TTT is of little value to predict the mechanism of syncope and the ILR implantation seems to be a useful and safe diagnostic strategy.