Beyond genomic studies of congenital heart defects through systematic modelling and phenotyping.

Congenital heart defects (CHDs), the most common congenital anomalies, are considered to have a significant genetic component. However, despite considerable efforts to identify pathogenic genes in patients with CHDs, few gene variants have been proven as causal. The complexity of the genetic architecture underlying human CHDs likely contributes to this poor genetic discovery rate.

Retrospective Review of the Image Quality of Monoplane Transesophageal Echocardiography in Prehospital Out-of-Hospital Cardiac Arrest: A Single Center Pilot Study.

Objectives: Out of Hospital Cardiac Arrest (OHCA) is a frequently encountered pathology with resultant poor outcomes in the majority of patients. Echocardiography has been utilized to help guide clinical decision making and monitor effectiveness of resuscitative efforts. Transthoracic echocardiography (TTE) the mainstay of point-of-care ultrasound (POCUS) real time resuscitative imaging has limitations, most notably is the disruption of closed chest compressions.

The G4 resolvase Dhx36 modulates cardiomyocyte differentiation and ventricular conduction system development.

Extensive genetic studies have elucidated cardiomyocyte differentiation and associated gene networks using single-cell RNA-seq, yet the intricate transcriptional mechanisms governing cardiac conduction system (CCS) development and working cardiomyocyte differentiation remain largely unexplored. Here we show that mice deleted for Dhx36 (encoding the Dhx36 helicase) in the embryonic or neonatal heart develop overt dilated cardiomyopathy, surface ECG alterations related to cardiac impulse propagation, and (in the embryonic heart) a lack of a ventricular conduction system (VCS). Heart snRNA-seq and snATAC-seq reveal the role of Dhx36 in CCS development and in the differentiation of working cardiomyocytes.

β3-Adrenergic receptor overexpression in cardiomyocytes preconditions mitochondria to withstand ischemia-reperfusion injury.

β3-Adrenergic receptor (β3AR) agonists have been shown to protect against ischemia-reperfusion injury (IRI). Since β3ARs are present both in cardiomyocytes and in endothelial cells, the cellular compartment responsible for this protection has remained unknown. Using transgenic mice constitutively expressing the human β3AR (hβ3AR) in cardiomyocytes or in the endothelium on a genetic background of null endogenous β3AR expression, we show that only cardiomyocyte expression protects against IRI (45 min ischemia followed by reperfusion over 24 h).