Descripción de dos familias con síndrome de QT largo / Description of 2 families with long QT syndrome

Resumen El síndrome de QT largo representa un grupo de desórdenes electrofisiológicos cardiacos, caracterizados por la prolongación del intervalo QT, que se asocian a muerte súbita, taquicardias ventriculares y síncope. Se presenta el caso de dos familias con la descripción clínica de los afectados, el estudio genético y el respectivo manejo, y se hace una breve actualización de la literatura sobre el síndrome de QT largo.

Abstract Long QT syndrome represents a group of electrophysiologic disorders characterized by a prolongation in the QT interval that are associated with sudden death, ventricular tachycardia and syncope. We present 2 families describing the clinical presentation, the genetic study and their respective treatment also there is a brief review about long QT syndrome.

Stressful Work Involvement and Inherited Long QT-Syndrome.

Aims: The long QT syndrome (LQTS) is an inherited cardiac disorder which predisposes the mutation carrier to ventricular arrhythmias that can lead to sudden death. The objective of the study was to study whether stressful work involvement (i.e. worrying about work and job dissatisfaction) is related to arrhythmic risk in LQTS. Study design: Cross-sectional study. Place and Duration of Study: The study took place in Finland in 2006 for the LQTS mutation carriers and 2007 for the general Finnish population. Methodology: The study subjects included 164 symptomatic and 229 asymptomatic LQTS mutation carriers from the Finnish LQTS registry and 1368 comparison subjects randomly derived from the population-based sample, Young Finns Study (YFS). Stressful work involvement was measured with questions derived from the Framingham type A scale. Results: Upon assessment of the stressful work involvement, symptomatic LQTS mutation carriers scored higher than asymptomatic LQTS mutation carriers (1.51 vs. 1.40, p=0.003, η²=0.022) and the general Finnish population (1.51 vs. 1.39, p<0.001, η²=0.012), while asymptomatic LQTS mutation carriers did not differ from the general Finnish population in the corresponding scores (1.40 vs. 1.39, p=0.374, η²<0.001). Conclusion: The results confirm the suggestion that perceived stress, in terms of stressful work involvement, may increase the likelihood of arrhythmic events in LQTS mutation carriers. Thus, individual stress proneness may be a risk factor for LQT symptoms, which should be taken into account in counseling LQTS patients. There is previous evidence that stress proneness can be modified by behavioral therapy.