Drug-induced block of the cardiac hERG (human Ether-à-go-go-Related Gene) potassium channel delays cardiac repolarization and increases the risk of Torsade de Pointes (TdP), a potentially lethal arrhythmia. A positive hERG assay has been embraced by regulators as a non-clinical predictor of TdP despite a discordance of about 30%. To test whether assaying concomitant block of multiple ion channels (Multiple Ion Channel Effects or MICE) improves predictivity we measured the concentration-responses of hERG, Nav1.5 and Cav1.2 currents for 32 torsadogenic and 23 non-torsadogenic drugs from multiple classes. We used automated gigaseal patch clamp instruments to provide higher throughput along with accuracy and reproducibility. Logistic regression models using the MICE assay showed a significant reduction in false positives (Type 1 errors) and false negatives (Type 2 errors) when compared to the hERG assay. The best MICE model only required a comparison of the blocking potencies between hERG and Cav1.2.
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http://dx.doi.org/10.1038/srep02100 | DOI Listing |
Cureus
December 2024
Department of Pediatrics/Division of Hospital Medicine, Children's National Hospital, Washington, DC, USA.
Circ Cardiovasc Interv
December 2024
Department of Pediatrics, Pediatric Cardiology, Stanford University, Palo Alto, CA. (J.K.Y., L.W., A.C.T., H.C., A.W.R., L.F.P., S.R.C., A.M.D., D.B.M.).
Background: Varying rates of nonsustained ventricular tachycardia (NSVT) have been reported early after transcatheter pulmonary valve replacement (TPVR) with the Harmony valve, but data regarding rhythm outcomes beyond hospital discharge are limited. This study aims to characterize ventricular arrhythmias after Harmony TPVR from implant through mid-term follow-up.
Methods: Ventricular arrhythmia data from postimplant telemetry and follow-up extended rhythm monitoring (ERM) were analyzed after Harmony TPVR.
J Med Case Rep
December 2024
Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Padjadjaran, Hasan Sadikin General Hospital, Bandung, Indonesia.
Background: This case highlights the management of concomitant acute myocarditis and congenital long QT syndrome with electrical storm and incessant Torsade de Pointes.
Case Presentation: An 18 years-old Southeast Asian para 1 abortus 0 (P1A0) postpartum patient with cesarean section owing to severe preeclampsia, acute lymphocytic myocarditis, and prolonged QT interval owing to long QT syndrome. She has incessant Torsade de Pointes treated with beta-blocker, lidocaine, overdrive pacing with a temporary transvenous pacemaker, left cardiac sympathetic denervation per video-assisted thoracoscopic surgery, and implantable cardioverter-defibrillator implantation.
J Mol Cell Cardiol Plus
December 2024
School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK.
The growing use of nitazene synthetic opioids heralds a new phase of the opioid crisis. However, limited information exists on the toxic effects of these drugs, aside from a propensity for respiratory depression. With restricted research availability of nitazenes, we used machine-learning-based tools to evaluate five nitazene compounds' interaction potential with the hERG potassium channel, a key drug antitarget in the heart.
View Article and Find Full Text PDFStem Cell Res Ther
December 2024
Department of Medical Physiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Introduction: A healthy young woman, age 26 without prior cardiac complications, experienced an out-of-hospital cardiac arrest caused by ventricular fibrillation (VF), which coincided with a fever. Comprehensive diagnostics including echo, CMR, exercise testing, and genetic sequencing, did not identify any potential cause. This led to the diagnosis of idiopathic VF and installment of an implantable cardioverter defibrillator, which six months later appropriately intervened another VF episode under conditions comparable to the first event.
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