The second Latin American catheter ablation registry ("II LAHRS EP registry").

Background: Patient's clinical characteristics, technical resources, center and operator volume, and operator experience and training are known variables impacting outcomes. Although international standards have been agreed to maximize the benefits of this therapy, regional and global differences still exist. Latin American information has not been updated in the last 10 years.

Associated factors with the occurrence of in-hospital cardiac arrest in patients admitted to internal medicine wards for non-cardiovascular causes.

Background And Objective: In-hospital cardiac arrest (IHCA) has a low survival rate, so it is essential to recognize the cases with the highest probability of developing it. The aim of this study is to identify factors associated with the occurrence of IHCA.

Material And Methods: A single-center case-control study was conducted including 65 patients admitted to internal medicine wards for non-cardiovascular causes who experienced IHCA, matched with 210 admitted controls who did not present with IHCA.

Fetal Laryngoscopy and Endoscopic Tracheal Intubation to Avoid ex utero Intrapartum Treatment in the Management of Fetuses with Suspected Airway Obstruction.

Introduction: Large congenital neck tumors can cause neonatal death due to airway obstruction. The aim of this study was to report outcomes of the first cohort of fetuses with neck masses and suspected airway obstruction managed with fetal laryngoscopy (FL) and fetal endoscopic tracheal intubation (FETI) to secure fetal airways and avoid ex utero intrapartum treatment (EXIT) procedure.

Methods: A prospective observational cohort of consecutive fetuses with neck masses that were candidates for an EXIT procedure due to suspicion of laryngeal and/or tracheal occlusion on ultrasonographic (US) or magnetic resonance imaging (MRI) examination were recruited for FL in a tertiary referral center in Queretaro, Mexico.

Management of Late Twin-to-Twin Transfusion Syndrome beyond 26 Weeks: Comparison between Fetoscopic Laser Therapy versus Traditional Management.

Introduction: A proportion of monochorionic diamniotic (MCDA) twin pregnancies complicated by twin-to-twin transfusion syndrome (TTTS) can present after 26 weeks of gestation. The aim of this study was to compare perinatal outcomes of late TTTS treated by fetoscopic laser coagulation versus traditional management with amniodrainage and/or emergency preterm cesarean delivery (CD).

Methods: Retrospective cohort from January 2012 to January 2023 of consecutive MCDA twin pregnancies complicated by TTTS after 26 weeks and evaluated in our referring centers.

Would a complete electrophysiological study allow us to make a correct diagnosis? Case report.

Background: Oblique course of some left accessory pathways is rare An incomplete electrophysiological study may confuse us between an oblique accessory pathway or the presence of two accessory pathways. The proximity of all atrial and ventricular electrograms, at each pole of the catheter, within the coronary sinus may be a novel finding.

Case Presentation: A 68-year-old woman patient presented arrhythmias with hypotension requiring electrical cardioversion.

QRS and QT Interval Modifications in Patients with Type 2 Diabetes Mellitus.

Introduction: Diabetes Mellitus imbricates inflammatory processes on their pathophysiology, it could affect cardiac electrophysiology. Cardiac inflammatory process leads electrocardiogram changes. Nevertheless, there are discrepancies about whether it prolongs or decreases waves and intervals such as QRS and QT.

Flexible Video Fetoscopy: Feasibility and Outcomes of a Novel Modality for Laser Therapy in Twin-to-Twin Transfusion Syndrome Presenting with Inaccessible Anterior Placenta.

Introduction: Identification of intertwin anastomosis may be challenging during fetoscopy in cases with complete anterior placenta. The aim of this study was to describe the technique, feasibility, and outcomes of flexible video fetoscopy for laser coagulation in monochorionic (MC) twin pregnancies with twin-to-twin transfusion syndrome (TTTS) presenting with inaccessible anterior placenta.

Methods: From April 2021 to March 2022, a prospective cohort of consecutive MC twin pregnancies complicated with TTTS presenting with anterior placenta after 20 weeks was recruited.

Uneven vectorial projection is the best explanation for QRS dispersion, not the asynchronic ventricular activation.

Background: It is believed that QRS dispersion (QRSd) is caused by asynchrony of ventricular activation, but there are no studies that prove it.

Objectives: To determine the mechanism that best explains QRSd in surface electrocardiogram (ECG).

Methods: Cross-sectional study in 95 consecutive patients (median age: 31.

Ventricular arrhythmias are associated with increased QT interval and QRS dispersion in patients with ST-elevation myocardial infarction.

Introduction And Objectives: The electrocardiogram continues to be essential in the diagnosis of acute myocardial infarction, and a useful tool in arrhythmic risk stratification. We aimed to determine which electrocardiographic variables can successfully predict the occurrence of ventricular arrhythmias (VA) in patients following ST-segment elevation myocardial infarction (STEMI).

Methods: We performed an observational study including 667 patients with STEMI admitted to the University Hospital in Sancti Spíritus, Cuba.

Twin-to-twin transfusion syndrome and coronavirus disease 2019: impact on diagnosis, referral, eligibility for fetoscopic laser therapy, and outcomes.

Background: Because of the progressive nature of twin-to-twin transfusion syndrome, difficulties in healthcare access during the COVID-19 pandemic may lead to delayed diagnosis and referral to fetal surgery centers, which may have repercussions on outcomes.

Objective: This study aimed to assess the clinical impact of the COVID-19 pandemic on pregnancies complicated with twin-to-twin transfusion syndrome.

Study Design: A retrospective cohort study of consecutive monochorionic diamniotic twin pregnancies complicated with twin-to-twin transfusion syndrome evaluated in our national referral fetal surgery center at Queretaro, Mexico, for possible surgical fetoscopy was conducted.

Prediction of neonatal survival according to lung-to-head ratio in fetuses with right congenital diaphragmatic hernia (CDH): A multicentre study from the Latin American CDH Study Group registry.

Objective: To evaluate survival outcomes of fetuses with right sided congenital diaphragmatic hernia (CDH) treated in Latin American centres and to assess the utility of left lung area to predict neonatal survival.

Methods: A retrospective cohort including isolated right sided CDH cases managed expectantly during pregnancy in six tertiary centers from five Latin American countries. The utility of the observed/expected lung-to-head ratio (O/E-LHR) in predicting neonatal survival was assessed, and the best cut-off to predict prognosis was automatically selected by decision tree analysis.

Increased QRS duration and dispersion are associated with mechanical dyssynchrony in patients with permanent right ventricular apical pacing.

Background: Permanent right ventricular apical pacing may have negative effects on ventricular function and contribute to development of heart failure. We aimed to assess intra- and interventricular mechanical dyssynchrony in patients with permanent right ventricular apical pacing, and to establish electrocardiographic markers of dyssynchrony.

Methods: 84 patients (46:38 male:female) who required permanent pacing were studied.

Brain Doppler abnormalities in fetuses with open spina bifida.

Background: To describe the brain Doppler changes in fetuses with isolated open spina bifida (OSB).

Study Design: Doppler ultrasound measurements including the umbilical artery (UA) pulsatility index (PI), middle cerebral artery (MCA) PI, and their combination into the cerebroplacental ratio (CPR) and umbilicocerebral ratio (UCR) were performed in a cohort of fetuses with OSB. Included patients were individually matched to a control group without structural anomalies and similar gestational ages.

New Parameter of the Second Half of the P-Wave, P-Wave Duration, and Atrial Conduction Times Predict Atrial Fibrillation during Electrophysiological Studies.

Objective: Several P-wave parameters reflect atrial conduction characteristics and have been used to predict atrial fibrillation (AF). The aim of this study was to determine the relationship between maximum P-wave duration (PMax) and new P-wave parameters, with atrial conduction times (CT), and to assess their predictive value of AF during electrophysiological studies (AF-EPS).

Subjects And Methods: This was a cross-sectional study in 153 randomly selected patients aged 18-70 years, undergoing EPS.

Vectorial theory surpasses the local theory in explaining the origin of P-wave dispersion.

Background: Local theory and the vectorial theory are used to explain the origin of P-wave dispersion (PWD). There are no previous studies that analyze both at the same time.

Objectives: We set out to determine the implication of local and vectorial theories in the origin of PWD.

Fetoscopic urethral meatotomy in fetuses with lower urinary tract obstruction by congenital megalourethra.

Background: To describe the perinatal outcomes of fetoscopic urethral meatotomy (FUM) in fetuses with lower urinary tract obstruction (LUTO) by congenital megalourethra.

Study Design: Between 2012 and 2020, 226 cases with LUTO were referred to our fetal surgery center in Queretaro, Mexico. We report the perinatal outcome of cases with LUTO by congenital megalourethra that were selected for FUM in an attempt to release the penile urethral obstruction.

Preoperative Cervical Length Predicts the Risk of Delivery within One Week after Pleuroamniotic Shunt in Fetuses with Severe Hydrothorax.

Objective: The objective of this study was to assess the predictive performance of preoperative cervical length (CL) for delivery within 1 week after pleuroamniotic shunting (PAS) in fetuses with severe hydrothorax.

Methods: A prospective cohort of fetuses with severe hydrothorax referred to our fetal surgery center in Querétaro, Mexico from January 2012 to July 2020. Severe fetal hydrothorax was diagnosed as an accumulation of fluid within the fetal pleural space accompanied with severe bilateral lung compression, mediastinal shift, polyhydramnios, and/or hydrops.

Single Uterine Access for Bilateral Pleuroamniotic Shunting in Fetuses with Severe Hydrothorax by an Internal Rotational Maneuver: Feasibility and Outcomes between Successful and Failed Procedures.

Objective: The objective of this study was to describe the feasibility of single percutaneous uterine access for bilateral pleuroamniotic shunting (PAS) in fetuses with severe hydrothorax by using an internal rotational maneuver and to compare perinatal outcomes between successful and failed procedures.

Methods: A prospective cohort of 25 fetuses with isolated bilateral hydrothorax and hydrops were referred to our fetal surgery center in Queretaro, Mexico during an 8-year period. Bilateral PAS was first attempted through a percutaneous single uterine access by internal rotation of the fetus, which was achieved by using the blunt tip of the same cannula, and in case of a failed procedure, a second uterine port was used to place the second shunt.

Open Fetal Microneurosurgery for Intrauterine Spina Bifida Repair.

Objectives: The aim of the study was to describe the feasibility of open fetal microneurosurgery for intrauterine spina bifida (SB) repair and to compare perinatal outcomes with cases managed using the classic open fetal surgery technique.

Methods: In this study, we selected a cohort of consecutive fetuses with isolated open SB referred to our fetal surgery center in Queretaro, Mexico, during a 3.5-year period (2016-2020).

Atrial conduction explains the occurrence of the P-wave dispersion phenomenon, but weakly.

Background: P-wave dispersion (PWD) is believed to be caused by inhomogeneous atrial conduction. This statement, however, is based on limited little solid evidence. The aim of this study was to determine the relationship between atrial conduction and PWD by means of invasive electrophysiological studies.