Pharmacological and device approach to therapy of inherited cardiac diseases associated with cardiac arrhythmias and sudden death

A genetic origin in diseases like the long QT syndrome, the Brugada syndrom e, or hypertrophic cardiomyopathy have been identified over the past years. These diseases have in common that they may result in sudden cardiac death of the patient. Recognition of patients based on their phenotype and appli cation in clinical practice of the knowledge acquired on the genetic basis may have a major impact on how we approach them. In the long QT syndrome se veral mutations have been identified both in the sodium and in the potassiu m channels. The different electrophysiological effects of the mutations lea d to a common phenotype: prolongation of the QT interval; but also to a com mon clinical impact: occurrence of malignant ventricular arrhythmias. Genet ics should help us in treating in a more rational way our patients dependin g on the type of mutation. In the Brugada syndrome, mutations affecting the sodium channel have been so far identified. The results are electrophysiol ogically opposite to the ones observed in the long QT syndrome. Thus differ ent mutations in the same gene lead to different functional consequences. A gain, identification and study of the right mutation may lead to a more rat ional treatment directed to correct the malfunction of the channel.