Sex Differences in Left Bundle Branch Area Pacing Versus Biventricular Pacing for Cardiac Resynchronization Therapy.

BACKGROUND: Women respond more favorably to biventricular pacing (BIVP) than men. Sex differences in atrioventricular and interventricular conduction have been described in BIVP studies. Left bundle branch area pacing (LBBAP) offers advantages due to direct capture of the conduction system. We hypothesized that men could respond better to LBBAP than BIVP. OBJECTIVES: This study aims to describe the sex differences in response to LBBAP vs BIVP as the initial cardiac resynchronization therapy (CRT). METHODS: In this multicenter prospective registry, we included patients with left ventricular ejection fraction ≤35% and left bundle branch block or a left ventricular ejection fraction ≤40% with an expected right ventricular pacing exceeding 40% undergoing initial CRT with LBBAP or BIVP. The composite primary outcome was heart failure-related hospitalization and all-cause mortality. The primary safety outcome included all procedure-related complications. RESULTS: There was no significant difference in the primary outcome when comparing men and women receiving LBBAP (P = 0.46), whereas the primary outcome was less frequent in women in the BIVP group than men treated with BIVP (P = 0.03). The primary outcome occurred less frequently in men undergoing LBBAP (29.9%) compared to those treated with BIVP (46.5%) (P = 0.004). In women, the incidence of the primary endpoint was 24.14% in the LBBAP group and 36.2% in the BIVP group; however, this difference was not statistically significant (P = 0.23). Complication rates remained consistent across all groups. CONCLUSIONS: Men and women undergoing LBBAP for CRT had similar clinical outcomes. Men undergoing LBBAP showed a lower risk of heart failure-related hospitalizations and all-cause mortality compared to men undergoing BIVP, whereas there was no difference between LBBAP and BIVP in women.

Extracción de electrodo intracardiaco ubicado en la vena interventricular posterior, con vaina de corte rotacional mecánica, en paciente con vena cava superior izquierda persistente / Extraction of intracardiac electrode located in the posterior interventricular vein, with a mechanical rotational cutting sheath, in a patient with persistent left superior vena cava

Resumen El uso de dispositivos cardiacos implantables ha aumentado en los últimos años, lo que ha generado un aumento en el número de procedimientos de extracción de electrodos a medida que se intervienen pacientes con un mayor número de comorbilidades. En la actualidad, la técnica percutánea de extracción es de elección en la mayoría de los pacientes debido a los excelentes resultados alcanzados y a una morbi-mortalidad asociada inferior a la de la extracción quirúrgica. No obstante, algunos pacientes pueden presentar retos que aumentan el grado de dificultad técnica del procedimiento, entre los que se encuentran variantes anatómicas, calcificaciones extensas o la necesidad de extraer electrodos de fijación pasiva. Se expone el caso de la extracción de un electrodo disfuncionante en una paciente portadora de marcapasos por bloqueo auriculoventricular completo, con estimulación diafragmática por electrodo ventricular de fijación pasiva implantado a través de una vena cava superior izquierda persistente en una vena posterolateral del seno coronario.

Abstract The use of cardiac electronic devices has increased over the last decades, which has generated an increase in the number of electrode extraction procedures, as a greater number of patients with multiple comorbidities undergo cardiac electronic device implantation. Currently, the percutaneous technique is preferable in most patients, given its excellent clinical results and lower morbidity and mortality compared to surgical extraction. Nonetheless, some clinical scenarios increase procedural difficulty, including anatomical variants, or the need to extract passive fixation leads. We present a case of a patient with pacemaker due to complete atrioventricular block, with diaphragmatic stimulation caused by a passive fixation ventricular electrode that was implanted in a posterolateral vein of the coronary sinus through a persistent left superior vena cava, who underwent successful transvenous lead extraction.

Improved all-cause mortality with left bundle branch area pacing compared to biventricular pacing in cardiac resynchronization therapy: a meta-analysis.

BACKGROUND: Left bundle branch area pacing (LBBAP) has emerged as a physiological alternative pacing strategy to biventricular pacing (BIVP) in cardiac resynchronization therapy (CRT). We aimed to assess the impact of LBBAP vs. BIVP on all-cause mortality and heart failure (HF)-related hospitalization in patients undergoing CRT. METHODS: Studies comparing LBBAP and BIVP for CRT in patients with HF with reduced left ventricular ejection fraction (LVEF) were included. The coprimary outcomes were all-cause mortality and HF-related hospitalization. Secondary outcomes included procedural and fluoroscopy time, change in QRS duration, and change in LVEF. RESULTS: Thirteen studies (12 observational and 1 RCT, n = 3239; LBBAP = 1338 and BIVP = 1901) with a mean follow-up duration of 25.8 months were included. Compared to BIVP, LBBAP was associated with a significant absolute risk reduction of 3.2% in all-cause mortality (9.3% vs 12.5%, RR 0.7, 95% CI 0.57-0.86, p < 0.001) and an 8.2% reduction in HF-related hospitalization (11.3% vs 19.5%, RR 0.6, 95% CI 0.5-0.71, p < 0.00001). LBBAP also resulted in reductions in procedural time (mean weighted difference- 23.2 min, 95% CI - 42.9 to - 3.6, p = 0.02) and fluoroscopy time (- 8.6 min, 95% CI - 12.5 to - 4.7, p < 0.001) as well as a significant reduction in QRS duration (mean weighted difference:- 25.3 ms, 95% CI - 30.9 to - 19.8, p < 0.00001) and a greater improvement in LVEF of 5.1% (95% CI 4.4-5.8, p < 0.001) compared to BIVP in the studies that reported these outcomes. CONCLUSION: In this meta-analysis, LBBAP was associated with a significant reduction in all-cause mortality as well as HF-related hospitalization when compared to BIVP. Additional data from large RCTs is warranted to corroborate these promising findings.

Intracardiac Echocardiography-guided Left Atrial Appendage Occlusion.

Left atrial appendage occlusion (LAAO) is a suitable alternative to oral anticoagulant therapy to prevent stroke in patients with AF. Most procedures are performed under transoesophageal echocardiography (TOE) guidance, which facilitates transseptal puncture, reduces the risk of procedurerelated complications and provides an additional method for device selection and real-time monitoring during device deployment. However, TOE has significant shortcomings, including the need for general anaesthesia/deep sedation as well as a significant risk of procedure-related adverse events. More recently, intracardiac echocardiography has been proposed as an alternative to TOE guidance during LAAO procedures. In this review, we summarise the available evidence as well as providing a step-by-step approach for intracardiac echocardiography-guided LAAO.

Impact of intracardiac echocardiography versus transesophageal echocardiography guidance on left atrial appendage occlusion procedures: A meta-analysis.

BACKGROUND: Intracardiac echocardiography (ICE) is increasingly used during left atrial appendage occlusion (LAAO) as an alternative to transesophageal echocardiography (TEE). The objective of this study is to evaluate the impact of ICE versus TEE guidance during LAAO on procedural characteristics and acute outcomes, as well the presence of peri-device leaks and residual septal defects during follow-up. METHODS: All studies comparing ICE-guided versus TEE-guided LAAO were identified. The primary outcomes were procedural efficacy and occurrence of procedure-related complications. Secondary outcomes included lab efficiency (defined as a reduction in in-room time), procedural time, fluoroscopy time, and presence of peri-device leaks and residual interatrial septal defects (IASD) during follow-up. RESULTS: Twelve studies (n = 5637) were included. There were no differences in procedural success (98.3% vs. 97.8%; OR 0.73, 95% CI 0.42-1.27, p = .27; I2 = 0%) or adverse events (4.5% vs. 4.4%; OR 0.81 95% CI 0.56-1.16, p = .25; I2 = 0%) between the ICE-guided and TEE-guided groups. ICE guidance reduced in in-room time (mean-weighted 28.6-min reduction in in-room time) without differences in procedural time or fluoroscopy time. There were no differences in peri-device leak (OR 0.93, 95% CI 0.68-1.27, p = 0.64); however, an increased prevalence of residual IASD was observed with ICE-guided versus TEE-guided LAAO (46.3% vs. 34.2%; OR 2.23, 95% CI 1.05-4.75, p = 0.04). CONCLUSION: ICE guidance is associated with similar procedural efficacy and safety, but could result in improved lab efficiency (as established by a significant reduction in in-room time). No differences in the rate of periprocedural leaks were found. A higher prevalence of residual interatrial septal defects was observed with ICE guidance.

Left Bundle Branch Pacing vs Left Ventricular Septal Pacing vs Biventricular Pacing for Cardiac Resynchronization Therapy.

BACKGROUND: Left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP) are considered to be acceptable as LBBAP strategies. Differences in clinical outcomes between LBBP and LVSP are yet to be determined. OBJECTIVES: The purpose of this study was to compare the outcomes of LBBP vs LVSP vs BIVP for CRT. METHODS: In this prospective multicenter observational study, LBBP was compared with LVSP and BIVP in patients undergoing CRT. The primary composite outcome was freedom from heart failure (HF)-related hospitalization and all-cause mortality. Secondary outcomes included individual components of the primary outcome, postprocedural NYHA functional class, and electrocardiographic and echocardiographic parameters. RESULTS: A total of 415 patients were included (LBBP: n = 141; LVSP: n = 31; BIVP: n = 243), with a median follow-up of 399 days (Q1-Q3: 249.5-554.8 days). Freedom from the primary composite outcomes was 76.6% in the LBBP group and 48.4% in the LVSP group (HR: 1.37; 95% CI: 1.143-1.649; P = 0.001), driven by a 31.4% absolute increase in freedom from HF-related hospitalizations (83% vs 51.6%; HR: 3.55; 95% CI: 1.856-6.791; P < 0.001) without differences in all-cause mortality. LBBP was also associated with a higher freedom from the primary composite outcome compared with BIVP (HR: 1.43; 95% CI: 1.175-1.730; P < 0.001), with no difference between LVSP and BIVP. CONCLUSIONS: In patients undergoing CRT, LBBP was associated with improved outcomes compared with LVSP and BIVP, while outcomes between BIVP and LVSP are similar.

Cómo realizar una punción transeptal de manera segura y exitosa / How to perform a transseptal puncture safely and effectively

Resumen Introducida inicialmente en la década de los cincuenta para la evaluación de las presiones de la aurícula izquierda y posteriormente para la realización de valvuloplastia mitral, la punción transeptal es, con frecuencia, la vía de acceso para efectuar procedimientos que involucren las cavidades izquierdas. En la actualidad, se usa comúnmente en los laboratorios de electrofisiología, tanto para la ablación de arritmias en cavidades izquierdas como para los procedimientos de cierre percutáneo de orejuela. No obstante, con la llegada de diversas técnicas para el manejo percutáneo de la válvula mitral, se espera un aumento progresivo de su uso por parte de cardiólogos intervencionistas. En este artículo, se revisa la técnica para hacer una punción transeptal segura y se dan recomendaciones y estrategias para el manejo de la punción transeptal difícil.

Abstract Initially described in 1959 as a technique to measure left atrial pressures, and later used during balloon mitral valvuloplasty, transeptal puncture (TSP) is frequently the access route for procedures involving the left heart chambers. Currently, it is mostly used in electrophysiology laboratories for arrhythmia ablation and during left atrial appendage occlusion procedures. However, with the ongoing development of percutaneous mitral valve interventions, it is expected that a greater number of interventional cardiologists will be using this technique in the near future. In this article, we review the technique to perform TSP safely, and we provide recommendations and different strategies to deal with difficult TSPs.

Cierre percutáneo de orejuela guiado con ecocardiografía intracardíaca vs. ecocardiografía transesofágica: una revisión sistemática / Left atrial appendage occlusion guided by intracardiac echocardiography vs. transesophageal echocardiography: a systematic review

Resumen El cierre percutáneo de orejuela se ha posicionado como una estrategia eficaz en la prevención de embolia en pacientes con fibrilación auricular. La mayoría de los procedimientos en el mundo se realizan mediante ecocardiografía transesofágica, que implica, en la mayoría de los casos, el uso de sedación profunda guiada por anestesiología o incluso anestesia general, lo que conlleva tiempos de sala y de procedimiento prolongados, potenciales retardos en la programación del procedimiento (por baja disponibilidad de servicios de anestesiología y de ecocardiografía) y exposición a los riesgos propios de la sedación profunda y la anestesia general. Adicionalmente, el mayor número de personas requeridos en sala para el cierre percutáneo de orejuela guiado por ecacardiografía transesofágica aumenta la cantidad de personas expuestas a radiación ionizante, particularmente el ecocardiografista, que se ubica próximo al angiógrafo y con frecuencia debe introducir sus manos en el campo de fluoroscopia. En los últimos años, la ecocardiografía intracardíaca ha cobrado importancia para guiar los procedimientos de cierre percutáneo de orejuela debido a su amplia disponibilidad en los laboratorios de electrofisiología, y a la posibilidad de realizar procedimientos con menor tiempo de uso de sala y de recuperación, ya que evita el uso de anestesia general y a que facilita los procedimientos con alta el mismo día, lo que se podría asociar a una disminución global de los costos de procedimientos. En este artículo se discute la evidencia actual que avala el uso de ecocardiografía intracardiaca en el cierre percutáneo de orejuela.

Abstract Left atrial appendage occlusion has proven to be an effective strategy in reducing the risk of stroke and systemic embolism in patients with atrial fibrillation. Worldwide, most left atrial appendage occlusions are performed using transesophageal echocardiography, which requires the use of monitored anesthesia care or general anesthesia, resulting in prolonged in-room and procedural times, delays in procedural scheduling (due to a low availability of anesthetic and echocardiography services) and the risks associated with anesthesia per se. Moreover, the additional personnel required to perform left atrial appendage occlusion guided by transesophageal echocardiography increases the number of people exposed to ionizing radiation, which is particularly high for the transesophageal echocardiography operator, who stands beside the fluoroscopy tube and frequently introduces his/her hands in the fluoroscopy field. Intracardiac echocardiography has gained acceptance to guide left atrial appendage occlusion in recent years, given its high availability in electrophysiology labs, as well as its potential to reduce in-room and procedural times, reduce the need for extensive recovery times, avoid the use of general anesthesia and facilitating same-day discharge, all of which could result in a reduction of total procedure-related costs. In this article, we discuss the evidence supporting the use of intracardiac echocardiography guidance during left atrial appendage occlusion.

Consenso colombiano de Falla Intestinal Crónica en Síndrome de Intestino Corto / Colombian Consensus on Chronic Intestinal Failure in Short Bowel Syndrome

Introducción. Los términos falla intestinal crónica, síndrome de intestino corto (SIC) y nutrición parenteral total son muy frecuentes en la práctica clínica cotidiana.El objetivo de esta guía fue establecer un marco de referencia de práctica clínica basado en el mejor de nivel de evidencia en pacientes con falla intestinal crónica secundaria a síndrome de intestino corto. Métodos. Se estableció un grupo de expertos interdisciplinarios en el manejo de la falla intestinal crónica quienes, previa revisión de la literatura escogida, se reunieron de manera virtual acogiendo el método Delphi para discutir una serie de preguntas seleccionadas, enfocadas en el contexto terapéutico de la falla intestinal crónica asociada al síndrome de intestino corto. Resultados. La recomendación del grupo de expertos colombianos es que se aconseje a los pacientes con SIC consumir dietas regulares de alimentos integrales que genere hiperfagia para compensar la malabsorción. Las necesidades proteicas y energéticas dependen de las características individuales de cada paciente; la adecuación del régimen debe ser evaluada a través de pruebas clínicas, antropométricas y parámetros bioquímicos. Se sugiere, especialmente a corto plazo después de la resección intestinal, el uso de análogos de somatostatina para pacientes con yeyunostomía de alto gasto en quienes el manejo de líquidos y electrolitos es problemático. En pacientes con SIC, que son candidatos a tratamiento con enterohormonas, Teduglutida es la primera opción. Conclusión. Existen recomendaciones en el manejo integral de la rehabilitación intestinal respaldadas ampliamente por este consenso y es importante el reconocimiento de alternativas terapéuticos enmarcadas en el principio de buenas prácticas clínicas.

Introduction. The terms chronic intestinal failure, short bowel syndrome (SBS), and total parenteral nutrition are very common in daily clinical practice. The objective of this guideline was to establish a reference framework for clinical practice based on the best level of evidence in patients with chronic intestinal failure secondary to short bowel syndrome. Methods. A group of interdisciplinary experts in the management of chronic intestinal failure was established who, after reviewing the selected literature, met virtually using the Delphi method to discuss a series of selected questions, focused on the therapeutic context of chronic intestinal failure associated with short bowel syndrome. Results. The recommendation of the Colombian expert group is that patients with SBS be advised to consume regular diets of whole foods that generate hyperphagia to compensate malabsorption. Protein and energy needs depend on the individual characteristics of each patient; the adequacy of the regimen must be evaluated through clinical, anthropometric tests and biochemical parameters. The use of somatostatin analogue is suggested, especially in the short term after bowel resection, for patients with high-output jejunostomy in whom fluid and electrolyte management is problematic. In SBS, who are candidates for enterohormonal therapy, Teduglutide is the first choice. Conclusion. There are recommendations on the comprehensive management of intestinal rehabilitation that are widely supported by this consensus and it is important to recognize therapeutic alternatives framed in the principle of good clinical practice.

Chlorhexidine gluconate pocket lavage to prevent cardiac implantable electronic device infection in high-risk procedures.

BACKGROUND: Infection is the most dreaded complication of cardiac implantable electronic devices (CIEDs), particularly in patients undergoing high-risk procedures (eg, generator change, device upgrade, lead/pocket revision). OBJECTIVE: The purpose of this study was to describe the impact of chlorhexidine gluconate (CHG) pocket lavage in high-risk procedures. METHODS: Patients from a prospective multicenter registry undergoing high-risk procedures were included. CHG lavage was performed by irrigating the generator pocket with 20 cc of 2% CHG without alcohol followed by and normal saline (NS) irrigation. Only NS irrigation was performed in the comparison group. The primary efficacy outcome was CIED-related infection at 12 months. The primary safety outcome was any CHG-associated adverse event. The secondary outcome was CIED infection during long-term follow-up. Propensity score matching (PSM) analysis was performed for the primary efficacy outcome. RESULTS: A total of 1504 patients were included. At 12-month follow-up, the primary efficacy outcome occurred in 4 of 904 CHG (0.4%) and 14 of 600 NS (2.3%) subjects (log-rank P = .005). On multivariate analysis, the use of CHG irrigation was associated with a lower risk of infection at 1-year follow-up (Cox proportional hazard ratio [HR] 0.138; 95% confidence interval [CI] 0.04-0.45; P = .001). This effect persisted during long-term follow-up. PSM demonstrated a significant reduction in CIED-related infection for the CHG group (0.2% vs 2.5%; Cox proportional HR 0.08; 95% CI 0.01-0.59; P = .014). No adverse events were associated with the use of CHG. CONCLUSION: CHG lavage during high-risk procedures was associated with a reduction in CIED-related infections without any adverse events reported. The benefits of CHG lavage were observed even during long-term follow up and in PSM analysis.

Sustained Apnea for Epicardial Access With Right Ventriculography: The SAFER Epicardial Approach.

BACKGROUND: Epicardial access (EA) has emerged as an increasingly important approach for the treatment of ventricular arrhythmias and to perform other interventional cardiology procedures. EA is frequently underutilized because the current approach is challenging and carries a high risk of life-threatening complications. OBJECTIVE: The purpose of this study was to determine the efficacy and safety of the SAFER (Sustained Apnea for Epicardial Access With Right Ventriculography) epicardial approach. METHODS: Consecutive patients who underwent EA with the SAFER technique were included in this multicenter study. The primary efficacy outcome was the successful achievement of EA. The primary safety outcomes included right ventricular (RV) perforation, major hemorrhagic pericardial effusion (HPE), and bleeding requiring surgical intervention. Secondary outcomes included procedural characteristics and any complications. Our results were compared with those from previous studies describing other EA techniques to assess differences in outcomes. RESULTS: A total of 105 patients undergoing EA with the SAFER approach from June 2021 to February 2023 were included. EA was used for ventricular tachycardia ablation in 98 patients (93.4%), left atrial appendage closure in 6 patients (5.7%), and phrenic nerve displacement in 1 patient (0.9%). EA was successful in all subjects (100%). The median time to EA was 7 minutes (IQR: 5-14 minutes). No cases of RV perforation, HPE, or need of surgical intervention were observed in this cohort. Comparing our results with previous studies about EA, the SAFER epicardial approach resulted in a significant reduction in major pericardial bleeding. CONCLUSIONS: The SAFER epicardial approach is a simple, efficient, effective, and low-cost technique easily reproducible across multiple centers. It is associated with lower complication rates than previously reported techniques for EA.

Left Bundle Branch Area Pacing Versus Biventricular Pacing as Initial Strategy for Cardiac Resynchronization.

BACKGROUND: Left bundle branch area pacing (LBBAP) for cardiac resynchronization therapy (CRT) is an alternative to biventricular pacing (BiVp). OBJECTIVES: The purpose of this study was to compare the outcomes between LBBAP and BiVp as an initial implant strategy for CRT. METHODS: In this prospective multicenter, observational, nonrandomized study, first-time CRT implant recipients with LBBAP or BiVp were included. The primary efficacy outcome was a composite of heart failure (HF)-related hospitalization and all-cause mortality. The primary safety outcomes were acute and long-term complications. Secondary outcomes included postprocedural New York Heart Association functional class and electrocardiographic and echocardiographic parameters. RESULTS: A total of 371 patients (median follow-up of 340 days [IQR: 206-477 days]) were included. The primary efficacy outcome occurred in 24.2% in the LBBAP vs 42.4% in the BiVp (HR: 0.621 [95% CI: 0.415-0.93]; P = 0.021) group, driven by a reduction in HF-related hospitalizations (22.6% vs 39.5%; HR: 0.607 [95% CI: 0.397-0.927]; P = 0.021) without significant difference in all-cause mortality (5.5% vs 11.9%; P = 0.19) or differences in long-term complications (LBBAP: 9.4% vs BiVp: 15.2%; P = 0.146). LBBAP resulted in shorter procedural (95 minutes [IQR: 65-120 minutes] vs 129 minutes [IQR: 103-162 minutes]; P < 0.001) and fluoroscopy times (12 minutes [IQR: 7.4-21.1 minutes] vs 21.7 minutes [IQR: 14.3-30 minutes]; P < 0.001), shorter QRS duration (123.7 ± 18 milliseconds vs 149.3 ± 29.1 milliseconds; P < 0.001), and higher postprocedural left ventricular ejection fraction (34.1% ± 12.5% vs 31.4% ± 10.8%; P = 0.041). CONCLUSIONS: LBBAP as an initial CRT strategy resulted in a lower risk of HF-related hospitalizations compared to BiVp. A reduction in procedural and fluoroscopy times, shorter paced QRS duration, and improvements in left ventricular ejection fraction compared with BiVp were observed.

Assisted reality device to guide cardiac implantable device programming in distant rural areas.

BACKGROUND: Patients with cardiac implantable electronic devices (CIEDs) living in rural areas have difficulty obtaining follow-up visits for device interrogation and programming in specialized healthcare facilities. OBJECTIVE: To describe the use of an assisted reality device designed to provide front-line workers with real-time online support from a remotely located specialist (Realwear HTM-1; Realwear) during CIED assistance in distant rural areas. METHODS: This is a prospective study of patients requiring CIED interrogation using the Realwear HMT-1 in a remote rural population in Colombia between April 2021 and June 2022. CIED interrogation and device programming were performed by a general practitioner and guided by a cardiac electrophysiologist. Non-CIED-related medical interventions were allowed and analyzed. The primary objective was to determine the incidence of clinically significant CIED alerts. Secondary objectives were the changes medical interventions used to treat the events found in the device interrogations regarding non-CIED related conditions. RESULTS: A total of 205 CIED interrogations were performed on 139 patients (age 69 ± 14 years; 54% female). Clinically significant CIED alerts were reported in 42% of CIED interrogations, consisting of the detection of significant arrhythmias (35%), lead malfunction (3%), and device in elective replacement interval (3.9%). Oral anticoagulation was initiated in 8% of patients and general medical/cardiac interventions unrelated to the CIED were performed in 52% of CIED encounters. CONCLUSION: Remote assistance using a commercially available assisted reality device has the potential to provide specialized healthcare to patients in difficult-to-reach areas, overcoming current difficulties associated with RM, including the inability to change device programming. Additionally, these interactions provided care beyond CIED-related interventions, thus delivering significant social and clinical impact to remote rural populations.

Anatomical considerations and clinical interpretation of the 12-lead ECG in the prone position: a prospective multicentre study.

AIMS: The aim of this study is to provide guidance for the clinical interpretation of electrocardiograms (ECGs) in prone position and to establish the electroanatomic explanations for the possible differences to supine position ECGs that may be observed. Additionally, to determine if prone back ECG can be used as an alternative to standard ECG in patients who may benefit from prone position. METHODS AND RESULTS: The ECG in supine (standard ECG), prone back (precordial leads placed on the patient's back), and prone anterior position (precordial leads placed in the standard position with the subjects in prone position) were prospectively examined on 85 subjects. Comparisons of ECG parameters between these positions were performed. Computed tomography (CT) scans were performed in both positions to determine possible electroanatomic aetiologies for prone-associated ECG changes. There were significant differences in QRS amplitude in Leads V1-V5 between supine and prone positions. Q waves were more frequently observed in prone back position vs. supine position (V1: 74.1 vs. 10.6%, P < 0.0001; V2: 23.5 vs. 0%, P < 0.0001, respectively). Flat and inverted T waves were more common in prone back leads (V1: 98 vs. 66%, P < 0.0001; V2: 96 vs. 8%, P < 0.0001; V3: 45 vs. 7%, P < 0.0001). The 3D-CT reconstructions measurements corroborated the significant inverse correlation between QRS amplitude and the distance from the centre of the heart to the estimated lead positions. CONCLUSION: In prone back position ECG, low QRS amplitude should not be misinterpreted as low voltage conditions, neither should Q waves and abnormal T waves are considered anteroseptal myocardial infarction. These changes can be explained by an increased impedance (due to interposing lung tissue) and by the increased distance between the electrodes to the centre of the heart.

The Emerging Role of Left Bundle Branch Area Pacing for Cardiac Resynchronisation Therapy.

Cardiac resynchronisation therapy (CRT) reduces the risk of heart failure-related hospitalisations and all-cause mortality, as well as improving quality of life and functional status in patients with persistent heart failure symptoms despite optimal medical treatment and left bundle branch block. CRT has traditionally been delivered by implanting a lead through the coronary sinus to capture the left ventricular epicardium; however, this approach is associated with significant drawbacks, including a high rate of procedural failure, phrenic nerve stimulation, high pacing thresholds and lead dislodgement. Moreover, a significant proportion of patients fail to derive any significant benefit. Left bundle branch area pacing (LBBAP) has recently emerged as a suitable alternative to traditional CRT. By stimulating the cardiac conduction system physiologically, LBBAP can result in a more homogeneous left ventricular contraction and relaxation, thus having the potential to improve outcomes compared with conventional CRT strategies. In this article, the evidence supporting the use of LBBAP in patients with heart failure is reviewed.

Current practice in transvenous lead extraction in Latin America: Latin American Heart Rhythm Association survey.

BACKGROUND: Transvenous lead extraction (TLE) is standard of care for the management of patients with cardiac implantable electronic device infection or lead-related complications. Currently, objective data on TLE in Latin America is lacking. OBJECTIVE: To describe the current practice standards in Latin American centers performing TLE. METHODS: An online survey was sent through the mailing list of the Latin American Heart Rhythm Society. Online reminders were sent through the mailing list; duplicate answers were discarded. The survey was available for 1 month, after which no more answers were accepted. RESULTS: A total of 48 answers were received, from 44 different institutions (39.6% from Colombia, 27.1% from Brazil), with most respondents (82%) being electrophysiologists. Twenty-nine institutions (66%) performed <10 lead extractions/year, with 7 (16%) institutions not performing lead extraction. Although most institutions in which lead extraction is performed reported using several tools, mechanical rotating sheaths were cited as the main tool (66%) and only 13% reported the use of laser sheaths. Management of infected leads was performed according to current guidelines. CONCLUSION: This survey is the first attempt to provide information on TLE procedures in Latin America and could provide useful information for future prospective registries. According to our results, the number of centers performing high volume lead extraction in Latin America is smaller than that reported in other continents, with most interventions performed using mechanical tools. Future prospective registries assessing acute and long-term success are needed.

Pulmonary Arteriography in Pulmonary Vein Stenosis.

A 43-year-old woman underwent radiofrequency pulmonary vein ablation for symptomatic paroxysmal atrial fibrillation. At 3 months, she developed worsening dyspnea and exercise intolerance; tests revealed severe stenosis in her right pulmonary veins at the venoatrial junction and an abnormally small left atrium.

La repolarización auricular y sus implicaciones clínicas / Atrial repolarisation and its clinical implications

Resumen La onda P en el electrocardiograma representa exclusivamente la despolarización de las aurículas puesto que la repolarización auricular queda oculta en el QRS. Sin embargo, cuando la repolarizacón auricular se hace evidente en el electrocardiograma se convierte en un elemento clave para el diagnóstico de algunas enfermedades. Diferente sucede en la repolarización ventricular; la repolarización auricular adopta el mismo sentido de la despolarización ya que sigue un sentido cráneo-caudal y se da desde el epicardio hacia el endocardio.

Abstract The P wave on the electrocardiogram exclusively represents atrial depolarisation, since atrial repolarisation is hidden in the QRS complex. However, when atrial repolarisation becomes evident in the electrocardiogram, it is a key element for the diagnosis of some diseases. Unlike what happens in ventricular repolarisation, atrial repolarisation adopts the same direction as depolarisation since it follows a craniocaudal course and it goes from the epicardium towards the endocardium.

Glucantime y prolongación del intervalo QTc: una combinación fatal / Glucantime and QTc interval prolongation: A fatal combination

Resumen La leishmaniosis cutánea es una enfermedad causada por un parásito pro tozoo intracelular; el glucantime es una opción terapéutica, aunque está asociado con alteraciones cardiovasculares, siendo la más frecuente la prolongación del intervalo QTc que se presenta entre el 17,8 % y 19 % de los pacientes. Si este efecto no es detectado a tiempo puede causar una arritmia fatal por torsade de pointes. Se presenta el caso de una paciente de 77 años quien se encontraba en tratamiento con glucantime intramus cular como tratamiento de leishmaniosis cutánea e ingresó por un cuadro clínico de hipocalemia severa refractaria y episodios de torsade de pointes; posteriormente, presentó fibrilación ventricular que no respondió a des fibrilación y reanimación. Las alteraciones en la repolarización cardiaca producidas por este medicamento se consideran secundarias a la acu mulación de compuestos pentavalentes y trivalentes en el miocardio. No existe tratamiento específico para esta situación, pero siempre se debe realizar manejo de soporte, evitar fármacos que prolonguen el intervalo QT, normalizar los niveles de potasio y de magnesio, elevar la frecuencia cardiaca con isoproterenol e implantar marcapaso transvenoso para lograr sobre-estimulación y reducción de los periodos refractarios.

Abstract Cutaneous leishmaniasis is a disease caused by an intracellular protozoan parasite; Glucantime is a therapeutic option, although it is associated with cardiovascular alterations, the most frequent being the prolongation of the QTc interval, that occurs between 17.8% and 19% of patients. If this effect is not early recognized, it can cause a fatal arrhythmia due to torsade de pointes. The case of a 77-year-old patient who was receiving intramuscu lar glucantime as treatment for cutaneous leishmaniasis is presented, the patient was admitted with severe refractory hypokalemia and episodes of torsade de pointes; subsequently, presented ventricular fibrillation that did not respond to defibrillation and resuscitation. The alterations in cardiac repolarization produced by this medicine are considered secondary to the accumulation of pentavalent and trivalent compounds in the myocardium. There is no specific treatment for this situation, but supportive manage ment should always be performed, avoid drugs that prolong the QT inter val, normalize potassium and magnesium levels, raise the heart rate with isoproterenol and implant transvenous pacemaker to achieve over-stimulation and reduction of refractory periods.