Generation of an isogenic CRISPR/Cas9-corrected control induced pluripotent stem cell line from a patient with autosomal dominant catecholaminergic polymorphic ventricular tachycardia with a heterozygous variant in cardiac calsequestrin-2.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited cardiac disease characterised by adrenergic-induced arrhythmias. The leading causes of CPVT are pathogenic variants in cardiac ryanodine receptor 2 (RYR2) and rarely, in cardiac calsequestrin-2 (CASQ2) genes, which are major components of Ca handling in cardiac myocytes. This resource builds upon an established induced pluripotent stem cell line generated from a family with autosomal dominant CPVT due to a heterozygous variant in CASQ2 c.

Reduced connexin-43 expression, slow conduction and repolarisation dispersion in a model of hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is an inherited heart muscle disease that is characterised by left ventricular wall thickening, cardiomyocyte disarray and fibrosis, and is associated with arrhythmias, heart failure and sudden death. However, it is unclear to what extent the electrophysiological disturbances that lead to sudden death occur secondary to structural changes in the myocardium or as a result of HCM cardiomyocyte electrophysiology. In this study, we used an induced pluripotent stem cell model of the R403Q variant in myosin heavy chain 7 (MYH7) to study the electrophysiology of HCM cardiomyocytes in electrically coupled syncytia, revealing significant conduction slowing and increased spatial dispersion of repolarisation - both well-established substrates for arrhythmia.

Generation of an induced pluripotent stem cell line from a patient with conduction disease and recurrent ventricular fibrillation with a sodium voltage-gated channel alpha subunit 5 (SCN5A) gene c.392 + 3A > G splice-site variant.

Variants in the sodium voltage-gated channel alpha subunit 5 gene (SCN5A) produce variable cardiac phenotypes including Brugada syndrome, conduction disease and cardiomyopathy. These phenotypes can lead to life-threatening arrhythmias, heart failure, and sudden cardiac death. Novel variants in splice-site regions of SCN5A require functional studies to characterise their pathogenicity as they are poorly understood.