Recientemente se han descrito mutaciones missense en la filamina C (FLNC) como causa de miocardiopatía. Los conocimientos sobre la patogenicidad y la correlación genotipo-fenotipo son escasos. Nuestro objetivo es describir un fenotipo cardiaco distintivo relacionado con mutaciones missense en el dominio ROD2 de FLNC (FLNC-mRod2).Incluimos 21 familias independientes con fenotipo de miocardiopatía hipertrófica (MCH)/miocardiopatía restrictiva (MCR) portadoras de variantes missense en FLNC-mRod2. Se estudió clínicamente a los portadores, además de hacer un cribado en cascada. Se analizó histológicamente el tejido miocárdico de tres corazones explantados y se comparó con un corazón portador de un truncamiento de FLNC y con un control sano. Se transfectaron plásmidos con mutaciones missense de FLNC y se analizaron mediante microscopía confocal.En 11 familias (52%) con 20 individuos evaluados (37 [23,7-52,7] años), 15 casos presentaron un fenotipo cardiaco consistente en una superposición de MCH-MCR e hipertrabeculación ventricular izquierda (apariencia de dientes de sierra). Durante una mediana de seguimiento de 6,49 años presentaron principalmente insuficiencia cardiaca avanzada (16 (80%) disfunción diastólica, 3 trasplantes cardiacos, 3 muertes por insuficiencia cardiaca) en ausencia de alteraciones de la conducción cardiaca o miopatía esquelética. Un total de 6 familias presentaban segregación genotipo-fenotipo leve, y las restantes eran mutaciones de novo. Se observó una remodelación de la matriz extracelular y distribución de la FLNC diferencial en los cardiomiocitos. Las células HT1080 y H9c2 no revelaron agregados citoplasmáticos de FLNC.Las variantes en FLNC-mRod2 exhiben una alta prevalencia de fenotipo solapado de MCR, MCH e hipertrabeculación en dientes de sierra, con una remodelación histopatológica cardiaca distintiva.Missense mutations in the filamin C (FLNC) gene have been reported as cause of inherited cardiomyopathy. Knowledge of the pathogenicity and genotype-phenotype correlation remains scarce. Our aim was to describe a distinctive cardiac phenotype related to rare missense FLNC variants in the ROD2 domain.We recruited 21 unrelated families genetically evaluated because of hypertrophic cardiomyopathy (HCM)/restrictive cardiomyopathy (RCM) phenotype carrying rare missense variants in the ROD2 domain of FLNC (FLNC-mRod2). Carriers underwent advanced cardiac imaging and genetic cascade screening. Myocardial tissue from 3 explanted hearts of a missense FLNC carrier was histologically analyzed and compared with an FLNC-truncating variant heart sample and a healthy control. Plasmids independently containing 3 FLNC missense variants were transfected and analyzed using confocal microscopy.Eleven families (52%) with 20 assessed individuals (37 [23.7-52.7]) years showed 15 cases with a cardiac phenotype consisting of an overlap of HCM-RCM and left ventricular hypertrabeculation (saw-tooth appearance). During a median follow-up of 6.49 years, they presented with advanced heart failure: 16 (80%) diastolic dysfunction, 3 heart transplants, 3 heart failure deaths) and absence of cardiac conduction disturbances or skeletal myopathy. A total of 6 families had moderate genotype-phenotype segregation, and the remaining were de novo variants. Differential extracellular matrix remodeling and FLNC distribution among cardiomyocytes were confirmed on histology. HT1080 and H9c2 cells did not reveal cytoplasmic aggregation of mutant FLNC.FLNC-mRod2 variants show a high prevalence of an overlapped phenotype comprising RCM, HCM and deep hypertrabeculation with saw-tooth appearance and distinctive cardiac histopathological remodeling.Full English text available from:www.revespcardiol.org/en

La monitorización remota de los dispositivos electrónicos cardiacos implantables ha demostrado ser fiable en cuanto a la transmisión de información; más eficiente que los seguimientos presenciales convencionales, dado que reduce las visitas presenciales, la carga de trabajo y los costes, y más segura, porque nos permite actuar de forma precoz ante alteraciones clínicas o técnicas que pueden comprometer la vida de nuestros pacientes.La introducción de esta tecnología supone una reorganización de la estructura de seguimiento de los dispositivos cardiacos implantables en nuestros centros, lo que hace crucial la protocolización de la respuesta a las alertas para poder aprovechar al máximo los recursos que nos brinda esta tecnología.

Introduction and objectives: This report presents the findings of the 2018 Spanish Catheter Ablation Registry. Methods: Data collection was retrospective. A standardized questionnaire was completed by each of the participating centers. Results: Data sent by 100 centers were analyzed, with a total number of 16 566 ablation procedures performed (the highest historically reported in this registry) for a mean of 165.5 +/- 127.9 and a median of 119 procedures per center. The ablation targets most frequently treated were atrial fibrillation (n = 4234; 25.6%), atrioventricular nodal re-entrant tachycardia (n = 3525; 21.3%) and cavotricuspid isthmus (n = 3425; 20.7%). A new peak was observed in the ablation of atrial fibrillation, increasing the distance from the other substrates. The overall success rate was 91%. The rate of major complications was 2.2%, and the mortality rate was 0.04%. A total of 2.1% of the ablations were performed in pediatric patients. Conclusions: The Spanish Catheter Ablation Registry enrolls systematically and continuously enrolls the ablation procedures performed in Spain, showing a progressive increasing in the number of ablations over the years, with a high success rate and low percentage of complications. (C) 2019 Sociedad Espanola de Cardiologia. Published by Elsevier Espana, S.L.U. All rights reserved.

Aims:Tachycardia mediated by septal accessory pathways (AP) and atypical atrioventricular nodal re-entry (AVNRT) require careful electrophysiologic evaluation for differential diagnosis. We aim to describe the differential behaviour of local ventriculo-atrial (VA) intervals which predicts the tachycardia mechanism.Methods and results:The local VA intervals at the para-Hisian septum were measured under three different situations: (i) tachycardia; (ii) sustained entrainment from the right ventricular apex (RVA); and (iii) continuous pacing from the RVA during sinus rhythm. Differences were computed as follows: Δ-VAentr = VA during entrainment - VA during tachycardia; and Δ-VApac = VA while pacing during sinus rhythm - VA during tachycardia. In contrast to AVNRT, we hypothesized that an invariable retrograde conduction through the septal AP will keep the result of the subtractions close to 0 ms in cases of ortodromic atrioventricular re-entrant tachycardia (AVRT). We analysed 55 atypical AVNRT (45% posterior type) and 82 AVRT (10 anteroseptal, 18 para-Hisian, 12 mid-septal, and 42 posteroseptal). Δ-VAentr was longer for AVNRT (98.5 ± 40.3 ms) compared with septal AP (-5.7 ± 19.3 ms; P < 0.001). A value of 50 ms showed 98.7% sensitivity and 92% specificity (AUC 0.99; 95% CI 0.98-1). According to physiological criteria, a negative Δ-VAentr remains unobserved in the case of AVNRT (positive predictive value 100% for septal AP). Δ-VApac was also longer for AVNRT (66.5 ± 14.6 ms) compared with septal AP (-9.7 ± 3.3 ms; P < 0.001). A value of 50 ms showed 100% sensitivity and 74% specificity (AUC 0.86; 95% CI 0.76-0.93).Conclusions:Delta of the local VA intervals enables distinction between atypical AVNRT and AVRT mediated by septal AP.

Aims Sensitivity to flecainide testing results in suboptimal findings in patients with Brugada syndrome (BrS), leading to safety concerns. Because cardiac syncope effectively predicts outcomes in BrS, we aimed to explore its predictive value in a large cohort of negative and positive responders (NR and PR) to standard flecainide testing. Methods and results We analysed the data of 251 consecutive patients, 177 NR vs. 74 PR, to flecainide testing, performed according to standard recommendations. Cardiac syncope was defined as syncope presenting without prodromal symptoms and in the absence of any specific situation. Comparing PR with NR, there were no differences regarding age (39 ± 15 vs. 44 ± 13 years; P = 0.052), male gender (70.1% vs. 66.2%; P = 0.553), and family history of sudden cardiac death in relatives younger than 45 years (27% vs. 27%; P = 1). Cardiac syncope was more frequent in PR (12.2% vs. 4%; P = 0.022), and previous sudden cardiac arrest (SCA) was documented only in PR (5.4% vs. 0%; P = 0.007). During the follow-up period (6.2 ± 3.3 years), one NR, who had previously experienced cardiac syncope, developed SCA 3 months after flecainide testing. Following resuscitation, a type I electrocardiogram was spontaneously recorded. The follow-up event rate was higher in patients with cardiac syncope, both in PR and in NR (P < 0.001 both). In a multivariate analysis, cardiac syncope was the unique variable that predicted adverse outcomes (hazard ratio 14.9, 95% confidence interval 1.84-121.25; P = 0.011). Conclusions In patients with false-negative responses to the provocative testing with flecainide, cardiac syncope predicts SCA, allowing a more extensive and individualized evaluation.

Background Debate regarding the prognosis of asymptomatic patients with Brugada syndrome (BrS) is possibly affected by the selection bias of survivors of sudden cardiac arrest (SCA). We aimed to determine variables influencing surveillance after SCA. Methods We analyzed a BrS cohort of 145 patients belonging to 37 families. We compared the clinical data and circumstances surrounding SCA (i.e., place of occurrence and people accompanying the subject) in 10 patients who survived an episode of SCA (Group A) vs. 27 deceased relatives (first or second degree) who suffered sudden cardiac death (SCD; Group B). Information concerning Group B was agreed upon by at least 3 relatives. A sub-analysis was performed considering families carrying a mutation in SCN5A (Group B-Mutant). Results Syncope was unique in predicting SCA in the BrS cohort. Comparing Groups A vs. B, there were no differences in the mean age at time of SCA/SCD (46.2 [SD 17.1] vs. 39.9 [SD 14.5] years; p = 0.271), gender (male 60% vs. 74.1%; p = 0.442), prior cardiomyopathy (0%), administration of cardiovascular treatments (anti-hypertensive and lipid-lowering drugs; 20% vs. 14.8%; p = 0.653) or conventional cardiovascular risk factors. Environmental circumstances surrounding the SCA/SCD were not significantly different between groups. Prior syncope was more frequent in Group A (80% vs. 3.7%; p < 0.001) and unique in predicting surveillance (p < 0.001). Group B-Mutant displayed equivalent data. Conclusions A previous syncope, as an alarm symptom, might contribute to better surveillance of SCA compared with subjects with SCA as the debut of BrS. The latter might behave as a factor of selection bias.

Atrial fibrillation (AF) is generally considered a progressive disease, typically evolving from paroxysmal through persistent to 'permanent' forms, a process attributed to electrical and structural remodelling related to both the underlying disease and AF itself. Medical treatment has yet to demonstrate clinical efficacy in preventing progression. Large clinical trials performed to date have failed to show benefit of rhythm control compared with rate control, but these trials primarily included patients at late stages in the disease process. One possible explanation is that intervention at only an early stage of progression may improve prognosis. Evolving observations about the progressive nature of AF, along with the occurrences of major complications such as strokes upon AF presentation, led to the notion that earlier and more active approaches to AF detection, rhythm-reversion, and maintenance of sinus rhythm may be a useful strategy in AF management. Approaches to early and sustained rhythm control include measures that prevent development of the AF substrate, earlier catheter ablation, and novel antiarrhythmic drugs. Improved classifications of AF mechanism, pathogenesis, and remodelling may be helpful to enable patient-specific pathophysiological diagnosis and therapy. Potential novel therapeutic options under development include microRNA-modulation, heatshock protein inducers, agents that influence Ca(2+) handling, vagal stimulators, and more aggressive mechanism-based ablation strategies. In this review, of research into the basis and management of AF in acute and early settings, it is proposed that progression from paroxysmal to persistent AF can be interrupted, with potentially favourable prognostic impact.

The Working Group on Cardiac Catheterization and Interventional Cardiology presents the yearly report on the data collected for the Spanish registry.Institutions provided their data voluntarily (online) and the information was analyzed by the Working Group's Steering Committee.Data were provided by 109 hospitals (71 public and 38 private) that mainly treat adults. There were 136 912 diagnostic procedures, 120 441 of which were coronary angiograms, slightly fewer than the year before, with a rate of 2979 diagnostic studies per million population. Percutaneous coronary interventions increased slightly to 65 909 procedures, for a rate of 1434 interventions per million population. Of the 99 110 stents implanted, 62% were drug-eluting stents. In all, 17 125 coronary interventions were carried out during the acute phase of myocardial infarction, 10.5% more than in 2011, representing 25.9% of the total number of coronary interventions. The most frequently performed intervention for adult congenital heart disease was atrial septal defect closure (292 procedures). The use of percutaneous mitral valvuloplasty continued to decline (258 procedures) and percutaneous aortic valve implantations increased by only 10% in 2012.In 2012, the only increase in hemodynamic activity occurred in the field of ST-elevation myocardial infarction, and the increasing trend had slowed for percutaneous aortic valve implantation and other procedures affecting structure.La Sección de Hemodinámica y Cardiología Intervencionista presenta su informe anual con los datos del registro de actividad nacional correspondientes a 2012.Los centros proporcionan sus datos voluntariamente. La información se introduce online y la analiza la Junta Directiva de la Sección de Hemodinámica.Enviaron datos 109 hospitales (71 centros públicos y 38 privados), que realizan su actividad predominantemente en adultos. Se realizaron 136.912 estudios diagnósticos (120.441 coronariografías), con una leve disminución respecto al año anterior, al igual que la tasa de 2.979 estudios diagnósticos por millón de habitantes. Los procedimientos intervencionistas coronarios mostraron un ascenso progresivo hasta 65.909 tras una ligera reducción en 2011, con una tasa de 1.434 intervenciones por millón de habitantes. Se implantaron 99.110 stents (el 62% farmacoactivos). Se llevaron a cabo 17.125 procedimientos en el infarto agudo de miocardio, lo que supone un incremento del 10,5% respecto a 2011 y representa el 25,9% del total de intervenciones coronarias percutáneas. El intervencionismo más frecuente en las cardiopatías congénitas del adulto fue el cierre de la comunicación interauricular, con 292 procedimientos. La valvuloplastia mitral sigue en descenso, con 258 casos. El implante percutáneo de válvulas aórticas ha moderado su crecimiento de años previos hasta un escaso 10%.El único aumento importante en la actividad en hemodinámica sigue teniendo relación con el infarto de miocardio con elevación de ST, mientras que el implante percutáneo de válvulas y otros procedimientos estructurales frenaron su crecimiento durante 2012.

Los electrodos de desfibrilación Sprint Fidelis presentan riesgo de disfunción precoz. La mayor parte de las series en la literatura provienen de un solo centro. Describimos la experiencia clínica en nueve centros españoles. Se analizaron los datos clínicos, del implante y el seguimiento de todos los pacientes con un electrodo Sprint Fidelis, describiendo los casos problema, calculando la supervivencia del electrodo a medio plazo e identificando posibles predictores de disfunción. Se incluyó un total de 378 electrodos en 376 pacientes (el 85,7% varones), con una media de edad de 64,9 ± 13,6 años. El 59,8% se implantó en pacientes con cardiopatía isquémica. La fracción de eyección ventricular izquierda era 33,4% ± 14,5%. En el 74,8% de los casos se implantó por punción subclavia izquierda. Tras un seguimiento medio de 30,9 ± 14 meses, 16 pacientes presentaron disfunción del electrodo; la supervivencia a 36 meses fue del 96,1%. En 11 electrodos ocurrió una disfunción aislada del sistema de sensado/estimulación; en 3, del sistema de alta energía, y en 2, de ambos. Una mejor función ventricular se asoció con una mayor probabilidad de fractura del electrodo (el 42,4% ± 16% frente al 33% ± 14,3%; p = 0,011); tres centros presentaron una tasa de fracturas superior al 10% y los seis restantes, inferior al 5%. En esta serie multicéntrica de 378 electrodos, la supervivencia estimada a 3 años resultó mayor que en series previas, con un perfil de presentación clínica similar de las disfunciones. La fracción de eyección ventricular izquierda y el centro implantador fueron variables asociadas a la presencia de disfunción. Sprint Fidelis defibrillation leads are prone to early failure. Most of the reported series come from a single institution. This paper describes the clinical experience in nine Spanish hospitals. Clinical, implant, and follow-up data of all patients with a Sprint Fidelis lead were analyzed. All cases of lead failure were identified, medium-term lead survival was calculated, and possible predictors for lead failure were determined. In total, 378 leads in 376 patients were studied. The mean age (male 85.7%) was 64.9±13.6 years. The majority of patients (59.8%) had ischemic heart disease. Mean left ventricular ejection fraction was 33.4%±14.5%. Left subclavian vein puncture was used in 74.8%. During a mean follow-up of 30.9±14 months, 16 lead failures have occurred, with a lead survival of 96.1% at 36 months after implantation. Eleven of 16 lead failures were caused by failure of pace/sense conductors, 3 by defects in the high-voltage conductor, and 2 by defects in both types of conductors. A less depressed left ventricular ejection fraction was associated with an increased probability of lead failure (42.4%±16% vs. 33%±14.3%; P=.011). Three hospitals presented a rate of lead failure higher than 10%; the rate was less than 5% in the remaining 6 hospitals. In this multicenter series of 378 leads, the 3-year estimated survival was higher than that reported in prior series. Clinical presentation of lead failures was similar to that reported previously. Left ventricular ejection fraction and hospital of implantation were variables associated to lead failure. Full English text available from: www.revespcardiol.org

Introduction and objectives: Sprint Fidelis defibrillation leads are prone to early failure. Most of the reported series come from a single institution. This paper describes the clinical experience in nine Spanish hospitals.Methods: Clinical, implant, and follow-up data of all patients with a Sprint Fidelis lead were analyzed. All cases of lead failure were identified, medium-term lead survival was calculated, and possible predictors for lead failure were determined.Results: In total, 378 leads in 376 patients were studied. The mean age (male 85.7%) was 64.9 +/- 13.6 years. The majority of patients (59.8%) had ischemic heart disease. Mean left ventricular ejection fraction was 33.4% +/- 14.5%. Left subclavian vein puncture was used in 74.8%. During a mean follow-up of 30.9 +/- 14 months, 16 lead failures have occurred, with a lead survival of 96.1% at 36 months after implantation. Eleven of 16 lead failures were caused by failure of pace/sense conductors, 3 by defects in the high-voltage conductor, and 2 by defects in both types of conductors. A less depressed left ventricular ejection fraction was associated with an increased probability of lead failure (42.4% +/- 16% vs. 33% +/- 14.3%; P=.011). Three hospitals presented a rate of lead failure higher than 10%; the rate was less than 5% in the remaining 6 hospitals.Conclusions: In this multicenter series of 378 leads, the 3-year estimated survival was higher than that reported in prior series. Clinical presentation of lead failures was similar to that reported previously. Left ventricular ejection fraction and hospital of implantation were variables associated to lead failure. (C) 2010 Sociedad Espanola de Cardiologia. Published by Elsevier Espana, S. L. All rights reserved.

A 58‐year‐old woman with symptomatic multiple monomorphic premature ventricular beats of a right ventricular outflow tract origin was referred for ablation. An inferior vena cava interruption with azygos continuation was discovered during catheter placement. This case describes positioning of the noncontact mapping array and successful radiofrequency ablation in this challenging anatomy. (PACE 2013; 36:e129–e131)

Background: In typical counterclockwise atrial flutter (AFL), the route of impulse propagation to anteroinferior right atrium (AIRA) during transient entrainment (TE) from the coronary sinus (CS) is expected to be similar to that during pacing from the same CS site during sinus rhythm (SR) when cavotricuspid isthmus (CTI) block has occurred. This could be used to identify CTI block during ablation procedures. Methods: Thirty‐six patients with AFL (cycle length [CL], 240 ± 25 ms) underwent CTI ablation during AFL. CS pacing was performed at a CL of 20 ms less than AFL CL before ablation (n = 36), and at several CL during SR with conduction through the CTI (n = 21) and after CTI block (n = 36). Results: TE with orthodromic activation of AIRA occurred in all 36 patients. Conduction time from CS to AIRA during TE (T‐entr, 199 ± 29 ms) was significantly longer than during pacing in SR (T‐CTI) at the same rate not only with CTI conduction (T‐CTI‐C, 135 ± 24 ms, P < 0.001), but also with CTI block (T‐CTI‐B, 186 ± 24 ms, P < 0.01). T‐entr did not correlate with T‐CTI‐C, but there was an excellent correlation between T‐entr and T‐CTI‐B (r = 0.874, P < 0.001). A “TE index” that corrected T‐CTI for individual T‐entr identified CTI block with 97% sensitivity and 91% specificity. T‐CTI at low rates differed from T‐CTI at high rates but correlated significantly with them. Conclusion: Comparison of conduction times during TE from the CS and during pacing from the same site and rate in SR can help to establish whether clockwise CTI block has been achieved in patients with typical AFL.

A 39‐year‐old female patient was referred for ablation of recurrent episodes of atrioventricular nodal reentrant tachycardia. A combination of an anomalous inferior vena cava with azygos continuation and a persistent left superior vena cava was discovered. A nonfluoroscopic navigation system was very useful for catheter ablation of the tachycardia in this unusual case of anomalous venous system of the heart.

Describir nuestra experiencia con la utilización del registrador implantable de eventos (REI) en un grupo de pacientes mayores con caídas frecuentes, y factores predictores de síncope de causa arrítmica.Estudio retrospectivo de pacientes mayores con caídas, sospecha de síncope y/o alteraciones en el ECG, a quienes tras una evaluación cardiológica se les implantó un REI, para esclarecer si las caídas estaban provocadas por una arritmia.Se han analizado 13 pacientes (7 varones con una edad media de 78 años), con una media de 3,3 caídas, a los que se implantó un REI como parte del estudio de las mismas. Han sido seguidos durante un periodo mínimo de 24 meses. Seis pacientes han mostrado una arritmia como causa de las caídas, registrada en el REI. En 5 casos se trataba de una bradiarritmia. El otro era una taquiarritmia. Cuatro pacientes no han presentado alteraciones del ritmo cardíaco durante las caídas. Los restantes 3 pacientes no han sufrido nuevas caídas durante el seguimiento.En este grupo seleccionado de pacientes con caídas, el REI ha detectado una causa arrítmica en un apreciable porcentaje de casos.To review our experience on using an implantable loop recorder (ILR) in patients with recurrent falls, when an arrhythmogenic cause is suspected.This is a retrospective, observational study of patients with repetitive unexplained falls, suspected syncope, or electrocardiographic abnormalities. All of them had been evaluated by a cardiologist, who decided to implant a loop recorder (ILR) for an accurate diagnosis.A total of 13 patients received an ILR. The average falls rate for the sample was 3.3. The mean age was 78 years, and 46% were female, with a mean follow-up period of 24 months. During this time, three patients did not suffer from a new fall. An arrhythmogenic diagnosis was obtained in 5 patients: bradycardia was identified in 4 cases, and tachycardia in one of them. The symptoms did not coincide with a documented arrhythmia in the rest of the patients.ILR is a helpful tool to establish an arrhythmogenic cause of unexplained and recurrent falls, in this selected sample of older adults.

La prévalence des syncopes augmente avec l'âge. Plus de la moitié d'entre elles correspondent à une réponse réflexe inappropriée du système nerveux autonome à certaines circonstances déclenchantes. Elles constituent le groupe des syncopes neurocardiogéniques réflexes ou vasovagales, liées soit à une chute tensionnelle, soit à une bradycardie, soit à l'association des deux mécanismes. La recherche du mécanisme réflexe responsable repose habituellement sur le tilt test (test provocatif) capable de reproduire les signes fonctionnels spontanés dans plus de la moitié des cas (tilt positif) par vasoplégie intense (80 % des cas) syncopale ou présyncopale. A l'inverse, le test à l'ATP (20 mg bolus i.v.) provoque une réaction cardio-inhibitrice vagale majeure indépendante de tous facteurs subjectifs (test descriptif) qui, chez le patient souffrant d'hypervagalisme sévère, peut provoquer une pause cardiaque supérieure à dix secondes (test ATP positif), avec ou sans symptômes associés. La positivité de ce test augmente avec l'âge et la présence de cardiopathie sous-jacente. Il a été démontré que l'implantation d'un pacemaker double chambre chez les patients ATP positif réduisait significativement le risque de récidive syncopale et que, sous stimulation permanente à 70 bpm, les éventuelles récidives devaient probablement correspondre à un phénomène vasoplégique associé, minoré jusqu'alors et ne correspondant pas à une indication de stimulation définitive. L'usage du test à l'ATP devrait pouvoir s'étendre au diagnostic de tout type de syncope ; sa positivité identifie un groupe de patients dont le mécanisme de la syncope est susceptible d'être amélioré par l'implantation d'un pacemaker définitif.The prevalence of syncope increases in elderly population. An inappropriate reflex reaction of the autonomous nervous system in specific circumstances is responsible for symptoms in more than 50% of cases. These neurocardiogenic or vasovagal syncopes are due to a vasoplegia or to a cardio-inhibitory reflex or to the association of both mechanisms. Reproducing the symptoms may contribute to identify the responsible mechanism of syncope; this objective is partly reached by the head-up tilt test — a provocative test —, which reproduces symptoms in about half of the cases, mainly by provoking a severe vasodilation with fall of blood pressure. On the opposite, the ATP test (20 mg i.v. bolus) — a descriptive test — provokes a strong cardio-inhibitory reflex independent from external factors like body position but it must be undertaken in a calm environment for preventing any anticipative sympathetic reaction. The test is considered positive if ATP produces a cardiac pause longer than 10 seconds and related symptoms are not taken into account for assessing the final result. ATP test positivity increases with age and with the presence of cardiac diseases. Permanent dual chamber pacing at 70 bpm has been shown to reduce significantly the syncope recurrences in patients with positive ATP test and to have no influence on patients with a negative test. The use of ATP test should be extended to all syncope screening. Its positivity identifies a group of patients in whom the mechanism of the syncope is susceptible to be improved by a permanent dual chamber pacing.