AKAP9 and polymorphic ventricular tachycardia: Disease-associated pathogenic variants in the A-Kinase Anchor Protein 9 (<i>AKAP9</i>) (MIM *604001) have been recently identified in patients with autosomal dominant long QT syndrome 11 (MIM #611820), lethal arrhythmia (ventricular fibrillation, polymorphic ventricular tachycardia), Brugada syndrome, and sudden unexpected death.