• Implanted cardiac defibrillators
• Single gene and family genetic studies
• Cardiac arrest
• Ventricular tachycardia
• Electrophysiology
• Genetics
• Cardiac arrhythmias and resuscitation science
• DISEASES
• CARDIAC PROCEDURES AND THERAPY

When the first four cases of catecholaminergic polymorphic tachycardia (CPVT) were reported over 40 years ago,1 we could only speculate about the incidence, cause and treatment of this elusive and lethal disease. Since then, important progress has been made in the understanding of CPVT, from bench to bedside. In 1999, Swan et al 2 described a linkage to chromosome 1q42-q43, and 2 years later, the gene was identified as coding for the ryanodine receptor gene (RYR2). RYR2 has a crucial role in regulating the calcium homeostasis in the cardiac myocyte. In recent years, additional genes (CASQ2, CALM2 and TRD) involved in the calcium homeostasis have been discovered and linked to CPVT, although fewer cases have been identified with these mutations. The chance of finding a gene mutation in a patient with a definitive clinical diagnosis of CPVT is only around 60%–70%, with the majority in the RYR2 gene.

In their Heart manuscript, Broendberg et al 3 looked at a Danish nationwide cohort of patients identified through their national hereditary heart database with a mean follow-up over 5 years. Their study showed a rather low prevalence of RYR2 mutations in the Danish population with a high number of events in previously asymptomatic family members. There were no deaths but a high rate of implantable cardioverter/defibrillator (ICD) implantation with complications due to multifocal …