Data of the COVID-19 mRNA-Vaccine V-Safe Surveillance System and Pregnancy Registry Reveals Poor Embryonic and Second Trimester Fetal Survival Rate. Comment on Stuckelberger et al. SARS-CoV-2 Vaccine Willingness among Pregnant and Breastfeeding Women during the First Pandemic Wave: A Cross-Sectional Study in Switzerland. 2021, , 1199.

Dr. Sarah Stuckelberger and her colleagues should be commended for their cross-sectional study assessing the willingness of Swiss pregnant and breastfeeding women to be vaccinated against SARS-CoV-2 [..

Study of the time-relationship of the mechano-electrical interaction in an animal model of tetralogy of Fallot: implications for the risk assessment of ventricular arrhythmias.

Objectives: The long-term outcome of tetralogy of Fallot (TOF) is determined by progressive right ventricular (RV) dysfunction through pulmonary regurgitation (PR) and the risk of malignant arrhythmia. Although mechano-electrical coupling in TOF is well-known, its time effect on the inducibility of arrhythmia remains ill-defined. The goal of this study was to investigate the mechano-electrical properties at different times in animals with chronic PR.

Progression of incomplete toward complete left bundle branch block: A clinical and electrocardiographic analysis.

Background: Complete left bundle branch block (cLBBB) is associated with increased cardiovascular mortality and heart failure. On the contrary, the clinical relevance of incomplete left bundle branch block (iLBBB) is less known. This study investigated the profile and outcome of iLBBB patients and assessed the risk of progression to cLBBB.

Haemodynamic management of patients with left ventricular assist devices using echocardiography: the essentials.

Mechanical circulatory support with continuous-flow left ventricular assist devices (LVADs) has emerged as a viable treatment modality for patients with advanced heart failure. LVAD support results in unique haemodynamic and echocardiographic alterations that must be understood to provide optimal care for these patients. In this review, we propose essential echocardiographic and haemodynamic elements for the assessment of optimal LVAD function based on the literature and the use of simulation software.

Failure to detect life-threatening arrhythmias in ICDs using single-chamber detection criteria.

Background: There are anecdotal reports of sudden death despite a functional implantable cardioverter defibrillator (ICD). We sought to describe scenarios leading to fatal or near-fatal outcome due to inappropriately inhibited ICD therapy in devices programmed with single-chamber detection criteria.

Methods: Programmed settings, episode lists, and intracardiac electrograms from 24 patients with a life-threatening event (n = 12) or fatal outcome (n = 12) related to failed ventricular arrhythmia detection were used to clarify the underlying scenario.

Gender differences in electro-mechanical characteristics of left bundle branch block: Potential implications for selection and response of cardiac resynchronization therapy.

Background: Female patients are underrepresented in cardiac resynchronization therapy (CRT) trials, although they show better CRT response compared to males and at shorter QRS durations. We hypothesized that differences in left bundle branch block (LBBB) characteristics and mechanical dyssynchrony might explain this gender disparity.

Methods: Patients presenting with true LBBB-morphology (including mid-QRS notching) on surface electrocardiograms (ECG) were selected.

Relation between electrical and mechanical dyssynchrony in patients with left bundle branch block: An electro- and vectorcardiographic study.

Background: Current guidelines select patients for cardiac resynchronization therapy (CRT) mainly on electrocardiographic parameters like QRS duration and left bundle branch block (LBBB). However, among those LBBB patients, heterogeneity in mechanical dyssynchrony occurs and might be a reason for nonresponse to CRT. This study assesses the relation between electrocardiographic characteristics and presence of mechanical dyssynchrony among LBBB patients.

Accuracy of computer-calculated and manual QRS duration assessments: Clinical implications to select candidates for cardiac resynchronization therapy.

Background: QRS duration (QRSD) plays a key role in the field of cardiac resynchronization therapy (CRT). Computer-calculated QRSD assessments are widely used, however inter-manufacturer differences have not been investigated in CRT candidates.

Methods: QRSD was assessed in 377 digitally stored ECGs: 139 narrow QRS, 140 LBBB and 98 ventricular paced ECGs.

Biventricular Paced QRS Area Predicts Acute Hemodynamic CRT Response Better Than QRS Duration or QRS Amplitudes.

Introduction: Vectorcardiographic (VCG) QRS area of left bundle branch block (LBBB) predicts acute hemodynamic response in cardiac resynchronization therapy (CRT) patients. We hypothesized that changes in QRS area occurring with biventricular pacing (BV) might predict acute hemodynamic CRT response (AHR).

Methods And Results: VCGs of 624 BV paced electrocardiograms (25 LBBB patients with 35 different pacing configurations) were calculated according to Frank's orthogonal lead system.

The electrocardiographic characteristics of septal flash in patients with left bundle branch block.

Aims: In patients with systolic heart failure and left bundle branch block (LBBB), septal flash (SF) movement has been described by echocardiography. We evaluated the prevalence of SF in LBBB and non-LBBB patients and evaluated whether specific electrocardiographic (ECG) characteristics within LBBB are associated with the presence of SF on echocardiography.

Methods And Results: One hundred and four patients with probable LBBB on standard 12-lead ECG were selected, 40 patients with non-LBBB served as controls.

Diagnostic accuracy of a novel method for detection of acute transmural myocardial ischemia based upon a self-applicable 3-lead configuration.

Background: Delayed medical attendance is a leading cause of death in patients with ST elevation myocardial infarction (STEMI).

Methods: We aimed to introduce, develop, and validate a novel method (RELF method) for detection of transmural ischemia based on a new and easy-to-use 3-lead configuration and orthonormalization of ST reference vectors (STDVN). The study included 60 patients undergoing coronary artery occlusion (CAO) during balloon inflation and 30 healthy subjects.

Alternans of the Ventricular Electrogram in Patients with an Implanted Cardioverter-Defibrillator.

Background: The occurrence and significance of alternans of the ventricular electrogram (VEGM) in patients with an implanted cardioverter-defibrillator (ICD) has been rarely reported.

Objectives And Methods: This report describes our observations of VEGM alternans documented in nine patients with an ICD (seven new cases and two previously published cases for comparison).

Results: We found seven new cases of near-field VEGM alternans and added two of our previously reported examples.

Different Methods to Measure QRS Duration in CRT Patients: Impact on the Predictive Value of QRS Duration Parameters.

Background: Measurements of QRS duration (QRSD) in patients undergoing cardiac resynchronization therapy (CRT) are not standardized. We hypothesized that both the measurement of QRSD and its predictive value on CRT response are sensitive to the method by which QRSD is measured.

Methods: Electrocardiograms (ECGs) pre- and post-CRT from 52 CRT patients (66 ± 12 years, 65% male) were retrospectively analyzed.

Variability in interpretation of the electrocardiogram in young athletes: an unrecognized obstacle for electrocardiogram-based screening protocols.

Aims: To assess in young athletes (i) the variability in the percentage of abnormal electrocardiograms (ECGs) using different criteria and (ii) the variability in ECG interpretation among cardiologists and sport physicians.

Methods And Results: Electrocardiograms of 138 athletes were categorized by seven cardiologists according to the original European Society of Cardiology (ESC) criteria by Corrado (C), subsequently modified by Uberoi (U), Marek (M), and the Seattle criteria (S); seven sports physicians only used S criteria. The percentage of abnormal ECGs for each physician was calculated and the percentage of complete agreement was assessed.

Bipolar electrograms characteristics at the left atrial-pulmonary vein junction: Toward a new algorithm for automated verification of pulmonary vein isolation.

Background: Verification of pulmonary vein isolation (PVI) is challenging because of the coexistence of PV and far-field potentials in bipolar electrograms recorded at the left atrial-pulmonary vein (LA-PV) junction.

Objective: The purpose of this study was to characterize algorithmically LA-PV potentials before and after PVI and to develop an algorithm to differentiate nonisolated from isolated PVs.

Methods: In 61 patients, we characterized-by type (morphology) and parameters-1440 electrograms recorded during sinus rhythm before and after PVI.

Atrioventricular block precipitated by isoproterenol.

An isoproterenol infusion was administered during an electrophysiologic study (EPS) in a patient with a history of near syncope, left bundle branch block, and no documented atrioventricular (AV) block. Isoproterenol precipitated classic 2:1 Infra-Hisian AV block most probably proximal to the site of recording a His-Purkinje potential consistent with right bundle branch activity. Paroxysmal AV block also occurred during isoproterenol washout at a different site located distal to the presumed right bundle branch potential.

Novel algorithmic methods in mapping of atrial and ventricular tachycardia.

Background: Conventional methods to assess local activation time (LAT) detect the peak of the bipolar electrogram (B-LATPeak) or the maximal negative slope of the unipolar electrogram (U-LATSlope). We evaluated 3 novel methods to assess LAT: onset (B-LATOnset) and center of mass (B-LATCoM) of bipolar electrogram, and maximal negative slope of unipolar electrogram within a predefined bipolar window (U-LATSlope-hybrid).

Methods And Results: In 1753 atrial tachycardia and 1426 ventricular tachycardia recordings, the performance of the methods in detecting LAT was evaluated pair-wise (eg, B-LATPeak versus B-LATOnset).