Therapeutic Efficacy of Mexiletine for Long QT Syndrome Type 2: Evidence From Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes, Transgenic Rabbits, and Patients.

Background: Despite major advances in the clinical management of long QT syndrome, some patients are not fully protected by beta-blocker therapy. Mexiletine is a well-known sodium channel blocker, with proven efficacy in patients with sodium channel-mediated long QT syndrome type 3. Our aim was to evaluate the efficacy of mexiletine in long QT syndrome type 2 (LQT2) using cardiomyocytes derived from patient-specific human induced pluripotent stem cells, a transgenic LQT2 rabbit model, and patients with LQT2.

Candidacy and long-term outcomes of subcutaneous implantable cardioverter-defibrillators in current practice in patients with hypertrophic cardiomyopathy.

Background: In patients with Hypertrophic Cardiomyopathy (HCM) S-ICD is usually the preferred option as pacing is generally not indicated. However, limited data are available on its current practice adoption and long-term follow-up.

Methods: Consecutive HCM patients with S-ICD implanted between 2013 and 2021 in 3 international centers were enrolled in this observational study.

A schedule for tapering glucocorticoid treatment in patients with severe SARS-CoV 2 infection can prevent acute adrenal insufficiency in the geriatric population.

Objective And Design: Glucocorticoids (GCs) have been widely used in symptomatic patients for the treatment of COVID-19. The risk for adrenal insufficiency must be considered after GC withdrawal given that it is a life-threatening condition if left unrecognized and untreated. Our study aimed to diagnose adrenal insufficiency early on through a GC reduction schedule in patients with COVID-19 infection.

Long QT syndrome: importance of reassessing arrhythmic risk after treatment initiation.

Background And Aims: Risk scores are proposed for genetic arrhythmias. Having proposed in 2010 one such score (M-FACT) for the long QT syndrome (LQTS), this study aims to test whether adherence to its suggestions would be appropriate.

Methods: LQT1/2/3 and genotype-negative patients without aborted cardiac arrest (ACA) before diagnosis or cardiac events (CEs) below age 1 were included in the study, focusing on an M-FACT score ≥2 (intermediate/high risk), either at presentation (static) or during follow-up (dynamic), previously associated with 40% risk of implantable cardioverter defibrillator (ICD) shocks within 4 years.

Effects of cohort, genotype, variant, and maternal β-blocker treatment on foetal heart rate predictors of inherited long QT syndrome.

Aims: In long QT syndrome (LQTS), primary prevention improves outcome; thus, early identification is key. The most common LQTS phenotype is a foetal heart rate (FHR) < 3rd percentile for gestational age (GA) but the effects of cohort, genotype, variant, and maternal β-blocker therapy on FHR are unknown. We assessed the influence of these factors on FHR in pregnancies with familial LQTS and developed a FHR/GA threshold for LQTS.