Outbreak of severe community-acquired bacterial infections among children in North Rhine-Westphalia (Germany), October to December 2022.

Purpose: In late 2022, a surge of severe S. pyogenes infections was reported in several European countries. This study assessed hospitalizations and disease severity of community-acquired bacterial infections with S.

Excitation-contraction coupling in zebrafish ventricular myocardium is regulated by trans-sarcolemmal Ca2+ influx and sarcoplasmic reticulum Ca2+ release.

Zebrafish (Danio rerio) have become a popular model in cardiovascular research mainly due to identification of a large number of mutants with structural defects. In recent years, cardiomyopathies and other diseases influencing contractility of the heart have been studied in zebrafish mutants. However, little is known about the regulation of contractility of the zebrafish heart on a tissue level.

Use of an active fixation lead and a subpectoral pacemaker pocket may not avoid Twiddler's syndrome.

Manipulation of a pacemaker with consequent malfunction of the device has been called Twiddler's syndrome. Use of active-fixation leads and subpectoral pacemaker pockets has been considered to help in avoiding this problem. We describe a child in whom twiddling was not prevented despite implantation of a lumenless atrial lead and insertion of the pacemaker generator in a subpectoral pocket.

Mechanical preconditioning enables electrophysiologic coupling of skeletal myoblast cells to myocardium.

Objective: The effect of mechanical preconditioning on skeletal myoblasts in engineered tissue constructs was investigated to resolve issues associated with conduction block between skeletal myoblast cells and cardiomyocytes.

Methods: Murine skeletal myoblasts were used to generate engineered tissue constructs with or without application of mechanical strain. After in vitro myotube formation, engineered tissue constructs were co-cultured for 6 days with viable embryonic heart slices.

Contractile properties of early human embryonic stem cell-derived cardiomyocytes: beta-adrenergic stimulation induces positive chronotropy and lusitropy but not inotropy.

Human embryonic stem cell-derived cardiomyocytes (hESC-CMs) provide the unique opportunity to study the very early development of the human heart. The aim of this study was to investigate the effect of calcium and beta-adrenergic stimulation on the contractile properties of early hESC-CMs. Beating clusters containing hESC-CMs were co-cultured in vitro with noncontractile slices of neonatal murine ventricles.

Ablation strategies in a patient with Belhassen tachycardia.

Unlabelled: The verapamil-sensitive Belhassen tachycardia is a ventricular reentrant tachycardia, involving left-sided Purkinje fibers and abnormal Purkinje or myocardial tissue. Ablation is feasible, targeting a diastolic fascicular potential in the apical left ventricle.

Case Report: We report on a 13-year-old girl with left posterior fascicular ventricular tachycardia.

Extended applications of the Amplatzer vascular plug IV in infants.

Objective: A variety of devices are available for transcatheter closure of unwanted shunts. We describe our experience with the use of the Amplatzer vascular plug IV in a consecutive series of infants.

Methods: A total of eight consecutive infants - all born preterm at gestational ages ranging from 24 to 35 weeks - undergoing transcatheter closure of unwanted shunts - persistently patent arterial duct in five patients, an aorta to right atrium fistula in one, multiple aortopulmonary collateral vessels in one, and an azygos vein to left atrium connection in one - are described.