BackgroundPredictive medicine relies on algorithms to determine clinical treatments tailored to each patient’s individual characteristics. Predictive models based on artificial intelligence have shown promise in identifying atrial fibrillation episodes; however, they rarely focus on short-term dynamic prediction. ObjectiveThis study aimed to evaluate the use of an artificial intelligence model and remote monitoring data extracted from pacemaker devices to predict the onset or worsening of arrhythmias in the short term. MethodsThis was a multicenter prospective observational study in which data from 314 patients were analyzed. A total of 65,243 data sequences were collected, of which 55,532 (85.1%) were used to train the algorithm. This model used 31-day records to predict whether the number of arrhythmic episodes would increase, decrease, or remain the same in the following 14 days. ResultsThe sensitivity and specificity of the generated predictions were calculated from 9711 prediction-observation pairs. The global sensitivity was 66.4% (95% CI 64.3%-68.3%), and specificity was 77.4% (95% CI 76.4%-78.4%). For patients with baseline arrhythmia, sensitivity was 76.8% (95% CI 74.6%-78.8%), and specificity was 39.6% (95% CI 35.8%-43.5%). The prediction for patients with no baseline arrhythmia showed a sensitivity of 39% (95% CI 35.1%-43%) and a specificity of 81% (95% CI 80.0%-81.9%). The analysis for the patient subgroup without history of atrial fibrillation (232/314, 73.9%) yielded a 69% sensitivity (95% CI 66.5%-71.5%) and an 80% specificity (95% CI 79.3%-81.3%). ConclusionsThis model was capable of predicting short-term increases or decreases in arrhythmic episodes with reasonable sensitivity and specificity using data collected through remote monitoring of implantable devices. The model’s performance is expected to improve progressively as more data samples become available, including demographic data and clinical records.

Background Data on the spontaneous onset of ventricular tachyarrhythmias (VTAs) in Brugada syndrome (BrS), including polymorphic ventricular tachycardia (PVT) and monomorphic ventricular tachycardia (MVT), remain limited. Objectives The goal of this study was to compare the clinical profile and mode of initiation of PVT and MVT in BrS. Methods This retrospective multicenter registry included 154 patients with BrS from 29 centers with documented VTA initiation captured by implantable cardioverter-defibrillator (94.9%) or electrocardiogram (5.1%). A total of 234 VTAs were analyzed, and initiation patterns were classified by using predefined electrocardiographic criteria. Results PVT was observed in 80.5% of patients, MVT in 16.9%, and both in 2.6%. Patients with MVT tended to be older, exhibit drug-induced Brugada electrocardiogram, and were more frequently White. Pause-dependent initiation occurred in approximately 25% of PVT and approximately 33% of MVT episodes. Coupling intervals initiating PVT were nonsignificantly shorter than for MVT (median 368 milliseconds vs 395 milliseconds), with a significantly lower prematurity index and faster early arrhythmia cycle length. Antecedent premature ventricular complexes were present in approximately 43% of both VTA types, commonly sharing morphology with the initiating premature ventricular complex. The prevalence of pathogenic/likely pathogenic SCN5A mutation did not differ between groups. Conclusions In this largest analysis to date of spontaneous VTA onset in BrS, MVT occurred in a substantial minority and was associated with older age, White ethnicity, drug-induced electrocardiogram pattern, and a preceding tachycardia. Initiation patterns were broadly similar across arrhythmia types, although PVT exhibited a significantly lower prematurity index and faster early cycle length despite only nonsignificant shorter coupling intervals. These findings refine the clinical and electrophysiological characterization of BrS-related arrhythmias and delineate distinct features of PVT and MVT initiation.

Background The results of ablation of sustained monomorphic ventricular tachycardia (SMVT) are suboptimal. For many patients with implantable cardioverter-defibrillators (ICDs), ICD electrograms (ICD-EGs) provide the only available information on SMVT. ICD-EGs have the ability to distinguish morphologically distinct SMVT and can be used for pace mapping. Objectives This study aimed to evaluate whether using ICD-EG information during an ablation procedure influences outcomes. Methods Patients with structural heart disease and SMVT documented by an ICD-EG, undergoing ablation, were randomly assigned in a 1:1 ratio to either an ablation incorporating ICD-EG data during the procedure (intervention group) or to conventional ablation. The ICD-EG obtained during induced SMVT and pace mapping was compared to ICD-EG from spontaneous SMVT to target the “clinical” SMVT for ablation. Ablation could be performed during SMVT (if tolerated), during sinus rhythm (“substrate ablation”), or both. Results A total of 15 centers randomized 260 patients. Characterization of induced SMVT as clinical/nonclinical and pace mapping were more frequent in the intervention group. Most patients underwent pure substrate ablation (65%), with complementary ablation during SMVT in 26%, showing no significant difference between groups. No differences were found in acute efficacy. In the intention-to-treat analysis, the primary endpoint of SMVT recurrence within 6 months postablation occurred in 46 (36%) patients in the intervention group and 59 (46%) in the conventional group (HR: 0.73; 95% CI: 0.49-1.07; P = 0.11). In the per-protocol analysis, SMVT recurrence at 6 months postablation reached statistical significance (HR: 0.66; 95% CI: 0.44-0.99; P = 0.045). During the entire follow-up period (44 ± 29 months), SMVT recurrence occurred in 67% and 76% (HR: 0.80; 95% CI: 0.60-1.08; P = 0.14). The number of SMVT episodes was significantly lower in the intervention group (HR: 0.45; 95% CI: 0.24-0.84; P = 0.013), as was the rate of electrical storm (23% vs 41%; HR: 0.54; 95% CI: 0.34-0.85; P = 0.007). There were no differences in ICD shocks. Conclusions In patients with structural heart disease and ICD-documented SMVT, using ICD-EG information during the ablation procedure to focalize ablation toward the clinical ventricular tachycardia is associated with a nonsignificant decrease in SMVT recurrence rate, a significant reduction in the number of ventricular tachycardia episodes, and a lower rate of arrhythmic storm.

Introduction and objectives: Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) is considered more reliable, efficient, and safer than conventional in-person follow-up. However, the implementation of RM is still suboptimal. This study aimed to analyze the impact of the COVID-19 pandemic on the rates of CIED implants and RM activations in Spain. Methods: The COVID-19 RM Spain Registry was used to analyze the monthly number of all CIED implantations and RM activations from January 2018 to December 2021. A descriptive analysis was performed using aggregated data from the five major CIED manufacturers. Results: A total of 205 345 CIEDs were recorded. The number of implants decreased sharply (48.2%) during the pandemic lockdown (March-June 2020) but gradually increased thereafter, compensating for the previous reduction. However, pacemakers and implantable cardiac defibrillators (ICD) showed an aggregate loss of 7% and 3%, respectively, from the annual average during 2020-2021. In contrast, cardiac resynchronization therapy defibrillators (CRT-D) increased by 17%, and pacemakers (CRT-P) by 4.5% over the 2-year period. The percentage of RM activations increased from 24.5% in 2018 to 49.0% in 2021, with a sharp increase during the lockdown. The RM activation rates consistently increased during the lockdown for all devices: pacemakers (14.4% vs 37.2%; P < .001); ICD (75.6% vs 94.2%; P < .001); CRT-D/ CRT-P (68.6-44.2% vs 81.6-61%; P < .001), and implantable loop recorders (50.2% vs 68.7%; P < .001). Conclusions: The significant decline in implants during the lockdown gradually recovered, except for pacemakers and ICD. However, the COVID-19 pandemic boosted RM for all CIEDs in Spain. (c) 2023 Sociedad Espanola de Cardiologia. Published by Elsevier Espana, S.L.U. All rights reserved.

Graphical Abstract The left panel depicts a female thorax in supine position, highlighting the 2 cm below the underwire bra (2BB) inframammary insertion and chest X-ray images of a patient with the device inserted in the proposed position. The middle panel shows boxplots with median, Q1, Q3, Min, and Max values for the R-wave amplitude at insertion, wound follow-up, and end of follow-up (left axis) and the percentage of patients for whom P-waves were visible at standard resolution at insertion, wound follow-up, and end of follow-up (right axis), and an electrocardiogram recorded by a device implanted in the 2BB position. The right panel shows mean scores for each questionnaire item (0 = not at all, 5 = very much).

Introducción: Se presentan los datos de implantes de sistemas de estimulación cardiaca en España en el año 2023.Métodos: El registro se basa en la información que los centros proporcionan tras el implante de dispositivos a la plataforma de registros de la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología, a través de la plataforma online del registro nacional, Cardiodispositivos. Otras fuentes de información incluyen: a) la cesión de datos de la industria fabricante y comercializadora; b) la tarjeta europea de paciente portador de marcapasos, y c) las bases de datos locales remitidas desde los centros implantadores.Resultados: Han participado en el registro 112 hospitales (30 más que en 2022). Se han comunicado 24.343 unidades (el 48,1% más que en 2022), frente a 45.120 comunicadas por Eucomed (European Confederation of Medical Suppliers Associations). De ellas, 1.646 marcapasos resincronizadores. El número de marcapasos sin cables experimentó el mayor incremento, con 963 dispositivos, un 18,1% más que en 2022. La indicación más frecuente fue el bloqueo auriculoventricular, seguido, por primera vez, de la taquiarritmia auricular con respuesta ventricular lenta. Los dispositivos incluidos en monitorización a distancia también crecieron (resincronizadores de alta energía, 71%; marcapasos resincronizadores, 63%; marcapasos convencionales, 28%), aunque más moderadamente.Conclusiones: En 2023 se ha experimentado un crecimiento en el número de hospitales participantes en el registro, un 48,1% en la comunicación de unidades al registro y un 18,1% en el implante de marcapasos sin cables. La monitorización a distancia también creció discretamente respecto a años previos.

BACKGROUND:There is limited information on the mode of arrhythmia initiation in idiopathic ventricular fibrillation (IVF). A non-pause-dependent mechanism has been suggested to be the rule. OBJECTIVES:The aim of this study was to assess the mode and characteristics of initiation of polymorphic ventricular tachycardia (PVT) in patients with short or long-coupled PVT/IVF included in THESIS (THerapy Efficacy in Short or long-coupled idiopathic ventricular fibrillation: an International Survey), a multicenter study involving 287 IVF patients treated with drugs or radiofrequency ablation. METHODS:We reviewed the initiation of 410 episodes of ≥1 PVT triplet in 180 patients (58.3% females; age 39.6 ± 13.6 years) with IVF. The incidence of pause-dependency arrhythmia initiation (prolongation by >20 ms of the preceding cycle length) was assessed. RESULTS:Most arrhythmias (n = 295; 72%) occurred during baseline supraventricular rhythm without ambient premature ventricular complexes (PVCs), whereas 106 (25.9%) occurred during baseline rhythm including PVCs. Nine (2.2%) arrhythmias occurred during atrial/ventricular pacing and were excluded from further analysis. Mode of PVT initiation was pause-dependent in 45 (15.6%) and 64 (60.4%) of instances in the first and second settings, respectively, for a total of 109 of 401 (27.2%). More than one type of pause-dependent and/or non-pause-dependent initiation (mean: 2.6) occurred in 94.4% of patients with ≥4 events. Coupling intervals of initiating PVCs were <350 ms, 350-500 ms, and >500 ms in 76.6%, 20.72%, and 2.7% of arrhythmia initiations, respectively. CONCLUSIONS:Pause-dependent initiation occurred in more than a quarter of arrhythmic episodes in IVF patients. PVCs having long (between 350 and 500 ms) and very long (>500 ms) coupling intervals were observed at the initiation of nearly a quarter of PVT episodes.

Introduction: Data on implants of cardiac pacing systems in Spain in 2023 are presented. Methods: The registry is based on the information provided by centers to the recording platform of the Heart Rhythm Association after device implantations, through Cardiodispositivos, the online platform of the National Registry. Other information sources include: a) data transfers from the manufacturing and marketing industry; b) the European pacemaker patient card; and c) local databases submitted by the implanting centers. Results: In 2023, 112 hospitals participated in the registry (30 more than in 2022). A total of 24 343 device implantations were reported (48.1% more than in 2022) compared with 45 120 reported by Eucomed (European Confederation of Medical Suppliers Associations). Of these, 1646 were cardiac resynchronization therapy pacemakers. The devices showing the largest increases were leadless pacemakers, with 963 devices implanted, representing an 18.1% increase over 2022. The most frequent indication was atrioventricular block followed, for the first time, by atrial tachyarrhythmia with slow ventricular response. The number of devices included in remote monitoring also increased (cardiac resynchronization therapy defibrillators, 71%; cardiac resynchronization therapy pacemakers, 63%; and conventional pacemakers, 28%), although more moderately. Conclusions: In 2023, there was an increase in the number of institutions participating in the registry. The reporting of device implantations rose by 48.1%, and the implantation of leadless pacemakers grew by 18.1%. Remote monitoring also experienced modest growth compared with previous years. (c) 2024 Sociedad Espa & ntilde;ola de Cardiologia. Published by Elsevier Espa & ntilde;a, S.L.U. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Abstract Background Cryoballoon ablation (CA) procedures require optimal occlusion of the pulmonary veins (PV), which is conventionally evaluated by iodine contrast injection through the catheter tip. This technique has some weaknesses such as risk of allergic reactions, nephrotoxicity, requirement of fluoroscopy (sometimes at high doses), requirement of a second operator, among others. PV pressure waveform assessment is an alternative method for confirming occlusion, however, multicentre assessment of periprocedural efficacy and safety is lacking. Purpose To describe the intra-procedural performance and safety of routine pressure-based CA. Methods In this independent prospective multicentre observational study, baseline and procedure data from consecutive pressure-guided CB ablations were collected. Operators were not required to have experience in pressure-guided CA for participating in the registry. They were asked to classify the pressure waveform curves into type 1 (presence of "a-wave" and/or symmetric "v-wave", meaning incomplete PV occlusion) and type 2 (absence of "a-wave" and asymmetric "v-wave", meaning complete PV occlusion), Figure 1. The primary endpoint was PV isolation in all veins without use of contrast. Procedure performance and adverse events were also analyzed. Results A total of 150 patients (mean age: 61 ± 10 y.) with paroxysmal (62%) or persistent AF (38%) were included and underwent pressure-guided CA in 9 centres from Spain. Complete PV isolation was achieved in 148 patients (98%). The operators switched to contrast use in 14 cases (9%), mainly to double check the occlusion. Total procedure and fluoroscopy time were 97 ± 39 and 19 ± 10 min respectively. There were 7 (4.7%) procedure related adverse events: 4 phrenic nerve palsy (3 of them were transient), 1 transient coronary ST elevation (before ablation), 1 gastroparesis and 1 femoral pseudoaneurysm. Most relevant results are summarized in Figure 2. Conclusion In this multicentre and multi-brand assessment, CA guided by pressure waveforms provided outstanding procedural outcomes, which were equivalent to those reported with the conventional approach. All operators could easily obtain and identify the waveform without a specific learning curve, avoiding the use of iodine contrast in most cases. The long-term efficacy of this approach will be presented in future analyses.Pressure waveforms types in cryoablationProcedural data

Obstructive sleep apnoea (OSA) and cardiac conduction disorders are pathologies with a rising prevalence due to increased life expectancy. Upper airway patency is affected by environmental factors that may be associated with seasonal periods. The ability to record the degree of nocturnal apnoea on a daily basis may provide a more accurate picture of seasonal variability. This study used an observational, cross-sectional design recruiting consecutive patients with Sorin/Livanova/Microport® pacemakers. The study assessed the seasonal influence on the daily degree of nocturnal apnoea over a minimum period of 180 days. The respiratory events were recorded using a pacemaker-integrated detection algorithm based on transthoracic impedance variation. A generalised linear repeated measure mixed model was used to study the seasonal effect. A sample of 101 subjects with a mean of 227 valid nights was compiled. Summer was associated with higher RDI (respiratory disturbance index) values and winter with lower values. The mean daily RDI ratio in summer was 1.099 times higher than in winter. Slight seasonal influences on the degree of nocturnal apnoea were detected through the daily observation of an unselected sample of pacemaker wearers. The degree of apnoea is higher in warmer months and lower in colder months.

La monitorización a distancia (MD) de los dispositivos cardiacos implantables (DCI) se considera más fiable, eficiente y segura que los convencionales seguimientos presenciales, aunque su implantación es aún subóptima. Este estudio pretende analizar el impacto de la pandemia de COVID-19 en las tasas de implantes y activaciones de MD de DCI en España. Se utilizó el Registro COVID-19 de MD en España para analizar el número mensual de todos los implantes de DCI y activaciones de MD desde enero de 2018 hasta diciembre de 2021 en España. Se sumaron los datos de los 5 principales fabricantes de DCI y se analizaron de manera descriptiva. Se registró un total de 205.345 DCI. El número de implantes disminuyó bruscamente (48,2%) con el confinamiento (marzo a junio de 2020) y aumentó progresivamente después hasta compensar la reducción previa, excepto en marcapasos y desfibriladores automáticos implantables (DAI), con una pérdida agregada (2020-2021) del 7 y el 3%, respectivamente, respecto a la media anual. Aumentaron la terapia de resincronización cardiaca con desfibrilador (TRC-D, 17%) y con marcapasos (TRC-P, 4,5%) a los 2 años. El porcentaje de activaciones de MD aumentó del 24,5% en 2018 al 49,0% en 2021, con un fuerte aumento durante el confinamiento. Las tasas de activación de MD aumentaron invariablemente durante el confinamiento con todos los dispositivos: marcapasos (el 14,4 frente al 37,2%; p < 0,001); DAI (el 75,6 frente al 94,2%; p < 0,001); TRC-D/TRC-P (del 68,6/44,2% al 81,6/61%; p < 0,001), y Holters implantables (el 50,2 frente al 68,7%; p < 0,001). La significativa reducción de los implantes que se produjo durante el confinamiento se recuperó gradualmente después, excepto los de marcapasos y DAI. La pandemia de COVID-19 impulsó la MD de todos los DCI en España. Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) is considered more reliable, efficient, and safer than conventional in-person follow-up. However, the implementation of RM is still suboptimal. This study aimed to analyze the impact of the COVID-19 pandemic on the rates of CIED implants and RM activations in Spain. The COVID-19 RM Spain Registry was used to analyze the monthly number of all CIED implantations and RM activations from January 2018 to December 2021. A descriptive analysis was performed using aggregated data from the five major CIED manufacturers. A total of 205 345 CIEDs were recorded. The number of implants decreased sharply (48.2%) during the pandemic lockdown (March-June 2020) but gradually increased thereafter, compensating for the previous reduction. However, pacemakers and implantable cardiac defibrillators (ICD) showed an aggregate loss of 7% and 3%, respectively, from the annual average during 2020-2021. In contrast, cardiac resynchronization therapy defibrillators (CRT-D) increased by 17%, and pacemakers (CRT-P) by 4.5% over the 2-year period. The percentage of RM activations increased from 24.5% in 2018 to 49.0% in 2021, with a sharp increase during the lockdown. The RM activation rates consistently increased during the lockdown for all devices: pacemakers (14.4% vs 37.2%; P < .001); ICD (75.6% vs 94.2%; P < .001); CRT-D/CRT-P (68.6-44.2% vs 81.6-61%; P < .001), and implantable loop recorders (50.2% vs 68.7%; P < .001). The significant decline in implants during the lockdown gradually recovered, except for pacemakers and ICD. However, the COVID-19 pandemic boosted RM for all CIEDs in Spain.

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

Abstract Funding Acknowledgements Type of funding sources: None. Background The Covid-19 pandemic has meant a very significant reduction in all urgent and non-urgent activity, including the implants of Cardiac Implantable electronic devices (CIEDs) throughout 2020. From the end of 2020 and throughout the year 2021, hospital activity has normalised, but it is uncertain whether the devices that were not implanted within 2020 have been delayed in time or actually lost. Purpose We sought to evaluate the pre and post-pandemic trends in CIEDs implantations from a large nationwide database in order to determine the global effect of the COVID-19 pandemic on CIEDs implants in Spain. Methods The Covid-19 Remote Monitoring Spain Registry (Covid-19 RM-Spain) is a survey supported by the Heart Rhythm Association of the Spanish Society of Cardiology to request the whole national data regarding the number of CIED´s implants and remote monitoring activations from the five main manufacturers classified according to each autonomous community (not by institutions).All data were aggregated and anonymized to analyse the total sample. Appropriate permissions were granted to use the data and a confidentiality agreement was signed in order to avoid any transmission of sensitive information. Results No institution objected to the use of their data, so the total number of devices implanted in Spain were obtained, which were 50258, 52994, 47330 and 54490 in 2018, 2019, 2020 and 2021 respectively. When we try to balance the drop in implants during 2020 and the subsequent increase experienced during 2021 against the average of 2018 and 2019, we have observed that approximately 2600 pacemakers (7%) and about 150 defibrillators (3.1%) have been "lost". With regard to the rest of the devices, adding up the differences between 2020 and 2021 and comparing them with the average for 2018-19, an increase of 419 Cardiac Resynchronization defibrillators (18%), 130 Cardiac Resynchronization Pacemakers (9.4%) and 1189 Implantable Loop recorders ( 26%) have been observed. Conclusion(s) In 2020 there was a large reduction in all CIEDs implants. In the most numerous devices (pacemakers), unlike the rest, the increment has not compensated for the reduction in implants that occurred in 2020 by the end of 2021. The marked increase in the number of cardiac resynchronization implants may suggest that the indication for single or dual-chamber defibrillator implantation may have finally evolved in a significant number of patients into an indication for cardiac resynchronization. Abbreviations: CRT-D: Cardiac resynchronization Therapy -Desfibrillator; CRT-P: Cardiac resynchronization Therapy -pacemaker; ICD: Implantable cardiac defibrillators; ILR: Implantable Loop recorders; LLPM: Leadles Pacemakers; PM: Pacemakers; S-ICD: Subcutaneous Implantable cardiac defibrillator.

BACKGROUND Pharmacological options for rate control in atrial fibrillation are scarce. Ivabradine was postulated to reduce the ven-tricular rate in this setting.OBJECTIVES The objectives of this study were to evaluate the mechanism of inhibition of atrioventricular conduction produced by ivabradine and to determine its efficacy and safety in atrial fibril-lation.METHODS The effects of ivabradine on atrioventricular node and ventricular cells were studied by in vitro whole-cell patch-clamp ex-periments and mathematical simulation of human action potentials. In parallel, a multicenter, randomized, open-label, phase III clinical trial compared ivabradine with digoxin for uncontrolled permanent atrial fibrillation despite b-blocker or calcium channel blocker treat-ment.RESULTS Ivabradine 1 mM inhibited "funny" current and rapidly activating delayed rectifier potassium channel current by 28.9% and 22.8%, respectively (P < .05). The sodium channel current and L-type calcium channel current were reduced only at 10 mM. Ivabradine slowed the firing frequency of a modeled human atrio- ventricular node action potential by 10.6% and induced a minimal prolongation of ventricular action potential. Thirty-five (51.5%) pa-tients were randomized to ivabradine and 33 (49.5%) to digoxin. The mean daytime heart rate decreased by 11.6 beats/min (-11.5%) in the ivabradine arm (P = .02) vs 19.6 (-20.6%) in the digoxin arm (P < .001), although the noninferiority margin of efficacy was not met (Z = -1.95; P = .97). The primary safety end point occurred in 3 patients (8.6%) on ivabradine and in 8 (24.2%) on digoxin (P = .10).CONCLUSION Ivabradine produced a moderate rate reduction in patients with permanent atrial fibrillation. The inhibition of funny current in the atrioventricular node seems to be the main mecha-nism responsible for this reduction. Compared with digoxin, ivabra-dine was less effective, was better tolerated, and had a similar rate of serious adverse events.

Atrial fibrillation (AF) is explained by anatomical and electrophysiological changes in the atria determined by high pressure, dilatation, infiltration and inflammation in the myocardium. There are some biomarkers implicated in these processes, namely, NT-proBNP, high sensitivity troponin (Hs-Tn), urate, galectin-3, ST2, C reactive protein and fibrinogen. The aim of this study was to assess differences in these biomarkers between patients with AF and healthy controls. We designed a cross-sectional study consecutively including all patients undergoing electrical cardioversion in our hospital for persistent AF and matched healthy controls. We included 115 patients with persistent non-valvular AF and 33 healthy subjects. The biomarkers NT-proBNP, ST2 and Hs-Tn T were significantly related to the presence of AF (1054 ± 833.30 vs. 58.31 ± 59.40, p < 0.001; 35.43 ± 15.89 vs. 27.43 ± 10.95, p < 0.001 and 10.25 ± 6.11 vs. 8.42 ± 6.85, p < 0.001, respectively). NT-proBNP was the best biomarker differentiating AF patients (area under the curve 0.995). The best NT-proBNP cut-off point to differentiate AF was 102 pg/mL; for Hs-Tn T it was 11.5 ng/L and for ST2 it was 37.7 ng/mL. It is possible that these biomarkers intervene at the onset of AF and have no role in AF maintenance.